600-uC-FS-001.book Page 1 Wednesday, October 10, 2012 12:03 PM C/ FS TM The Embedded File System User's Manual 600-uC-FS-001.book Page 2 Wednesday, October 10, 2012 12:03 PM Micrim 1290 Weston Road, Suite 306 Weston, FL 33326 USA www.micrium.com Designations used by companies to distinguish their products are often claimed as trademarks. In all instances where Micrim Press is aware of a trademark claim, the product name appears in initial capital letters, in all capital letters, or in accordance with the vendor's capitalization preference. Readers should contact the appropriate companies for more complete information on trademarks and trademark registrations. All trademarks and registered trademarks in this book are the property of their respective holders. Copyright (c) 2012 by Micrim except where noted otherwise. All rights reserved. Printed in the United States of America. No part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher; with the exception that the program listings may be entered, stored, and executed in a computer system, but they may not be reproduced for publication. The programs and code examples in this book are presented for instructional value. The programs and examples have been carefully tested, but are not guaranteed to any particular purpose. The publisher does not offer any warranties and does not guarantee the accuracy, adequacy, or completeness of any information herein and is not responsible for any errors or omissions. The publisher assumes no liability for damages resulting from the use of the information in this book or for any infringement of the intellectual property rights of third parties that would result from the use of this information. 600-uC-FS-001 600-uC-FS-001.book Page 3 Wednesday, October 10, 2012 12:03 PM Table of Contents Chapter 1 1-1 1-2 1-3 1-4 Introduction .......................................................................................... 15 C/FS .................................................................................................... 15 Typical Usages ..................................................................................... 17 Why FAT? ............................................................................................. 17 Chapter Contents ................................................................................. 18 Chapter 2 2-1 2-1-1 2-1-2 2-1-3 2-1-4 2-1-5 2-1-6 2-1-7 2-1-8 C/FS Architecture .............................................................................. 23 Architecture Components ................................................................... 25 Your Application ................................................................................... 25 C-LIB (Libraries) ................................................................................. 25 POSIX API Layer .................................................................................. 25 FS Layer ............................................................................................... 26 File System Driver Layer ...................................................................... 27 Device Driver Layer .............................................................................. 27 C-CPU ................................................................................................ 28 RTOS Layer .......................................................................................... 28 Chapter 3 3-1 3-2 3-3 3-4 3-5 3-6 3-7 3-8 3-9 3-10 3-11 C/FS Directories and Files ................................................................. 29 Application Code ................................................................................. 32 CPU ....................................................................................................... 34 Board Support Package (BSP) ............................................................ 35 C/CPU, CPU Specific Source Code .................................................. 36 C/LIB, Portable Library Functions ..................................................... 38 C/Clk, Time/Calendar Management .................................................. 39 C/CRC, Checksums and Error Correction Codes ............................ 41 C/FS Platform-Independent Source Code ........................................ 42 C/FS FAT Filesystem Source Code ................................................... 45 C/FS Memory Device Drivers ............................................................ 46 C/FS Platform-Specific Source Code ............................................... 50 3 600-uC-FS-001.book Page 4 Wednesday, October 10, 2012 12:03 PM Table of Contents 3-12 3-13 C/FS OS Abstraction Layer ............................................................... 51 Summary .............................................................................................. 52 Chapter 4 4-1 4-2 4-3 4-4 4-5 Useful Information ................................................................................ 59 Nomenclature ....................................................................................... 59 C/FS Device and Volume Names ...................................................... 61 C/FS File and Directory Names and Paths ....................................... 62 C/FS Name Lengths ........................................................................... 64 Resource Usage ................................................................................... 65 Chapter 5 5-1 5-2 5-3 5-4 5-5 5-6 5-7 5-8 5-8-1 5-8-2 Devices and Volumes .......................................................................... 67 Device Operations ............................................................................... 68 Using Devices ...................................................................................... 69 Using Removable Devices ................................................................... 71 Raw Device IO ...................................................................................... 72 Partitions .............................................................................................. 73 Volume Operations .............................................................................. 76 Using Volumes ..................................................................................... 77 Using Volume Cache ............................................................................ 79 Choosing Cache Parameters ............................................................... 81 Other Caching and Buffering Mechanisms ......................................... 82 Chapter 6 6-1 6-1-1 6-1-2 6-1-3 6-1-4 6-1-5 6-2 6-2-1 6-2-2 6-2-3 Files ...................................................................................................... 83 File Access Functions .......................................................................... 84 Opening Files ....................................................................................... 85 Getting Information About a File ......................................................... 86 Configuring a File Buffer ...................................................................... 87 File Error Functions .............................................................................. 88 Atomic File Operations Using File Lock .............................................. 88 Entry Access Functions ....................................................................... 89 File and Directory Attributes ................................................................ 90 Creating New Files and Directories ..................................................... 91 Deleting Files and Directories ............................................................. 92 Chapter 7 7-1 Directories ............................................................................................ 93 Directory Access Functions ................................................................ 94 4 600-uC-FS-001.book Page 5 Wednesday, October 10, 2012 12:03 PM Chapter 8 8-1 8-2 8-3 8-3-1 8-3-2 8-3-3 8-3-4 8-3-5 8-4 8-5 POSIX API ............................................................................................. 95 Supported Functions ........................................................................... 96 Working Directory Functions ............................................................... 97 File Access Functions .......................................................................... 98 Opening, Reading and Writing Files .................................................. 100 Getting or Setting the File Position ................................................... 103 Configuring a File Buffer .................................................................... 104 Diagnosing a File Error ...................................................................... 106 Atomic File Operations Using File Lock ............................................ 106 Directory Access Functions .............................................................. 107 Entry Access Functions ..................................................................... 109 Chapter 9 9-1 9-1-1 9-2 Device Drivers .................................................................................... 111 Provided Device Drivers .................................................................... 112 Driver Characterization ...................................................................... 113 Drivers comparison ............................................................................ 115 Chapter 10 10-1 10-2 10-2-1 10-3 10-3-1 10-3-2 10-4 10-5 10-6 10-7 10-7-1 10-7-2 FAT File System ................................................................................. 117 Why Embedded Systems Use FAT ................................................... 117 Organization of a FAT Volume ........................................................... 118 Organization of Directories and Directory Entries ............................ 119 Organization of the File Allocation Table .......................................... 120 FAT12 / FAT16 / FAT32 ...................................................................... 122 Short and Long File Names ............................................................... 123 Formatting .......................................................................................... 126 Sources of Corruption in FAT Volumes ............................................. 127 Optional Journaling System .............................................................. 127 Licensing Issues ................................................................................. 129 Licenses for Long File Names (LFNs) ............................................... 129 Extended File Allocation Table (exFAT) ............................................ 129 Chapter 11 11-1 11-2 RAM Disk Driver ................................................................................. 131 Files and Directories .......................................................................... 131 Using the RAM Disk Driver ................................................................ 132 5 600-uC-FS-001.book Page 6 Wednesday, October 10, 2012 12:03 PM Table of Contents Chapter 12 12-1 12-2 12-2-1 12-2-2 12-2-3 12-3 12-3-1 12-3-2 12-3-3 SD/MMC Drivers ................................................................................ 135 Files and Directories .......................................................................... 137 Using the SD/MMC CardMode Driver ............................................... 138 SD/MMC CardMode Communication ............................................... 141 SD/MMC CardMode Communication Debugging ............................ 144 SD/MMC CardMode BSP Overview .................................................. 148 Using the SD/MMC SPI Driver ........................................................... 150 SD/MMC SPI Communication ........................................................... 153 SD/MMC SPI Communication Debugging ........................................ 154 SD/MMC SPI BSP Overview .............................................................. 157 Chapter 13 13-1 13-2 13-3 13-3-1 13-3-2 13-4 13-4-1 13-4-2 13-5 13-6 13-7 13-8 13-8-1 13-8-2 13-8-3 13-8-4 NAND Flash Driver ............................................................................. 159 Getting Started ................................................................................... 160 Architecture Overview ....................................................................... 167 NAND Translation Layer .................................................................... 168 Translation Layer Configuration ........................................................ 171 Translation Layer Source Files .......................................................... 178 Controller Layer .................................................................................. 178 Generic Controller Layer Implementation ......................................... 179 Part Layer ........................................................................................... 181 Board Support Package - Generic Controller .................................. 185 Board Support Package - Other Controllers .................................... 186 Performance Considerations ............................................................. 187 Development Guide ........................................................................... 188 BSP Development Guide - Generic Controller ................................. 189 Generic Controller Extension Development Guide ........................... 191 ECC Module Development Guide ..................................................... 193 Controller Layer Development Guide ................................................ 194 Chapter 14 14-1 14-2 14-3 14-3-1 14-3-2 14-3-3 NOR Flash Driver ............................................................................... 199 Files and Directories .......................................................................... 200 Driver and Device Characteristics ..................................................... 202 Using a Parallel NOR Device ............................................................. 204 Driver Architecture ............................................................................. 208 Hardware ............................................................................................ 208 NOR BSP Overview ............................................................................ 210 6 600-uC-FS-001.book Page 7 Wednesday, October 10, 2012 12:03 PM 14-4 14-4-1 14-4-2 14-5 14-5-1 14-5-2 14-5-3 14-5-4 14-5-5 Using a Serial NOR Device ................................................................ 211 Hardware ............................................................................................ 212 NOR SPI BSP Overview ..................................................................... 213 Physical-Layer Drivers ....................................................................... 214 FSDev_NOR_AMD_1x08, FSDev_NOR_AMD_1x16 .......................... 215 FSDev_NOR_Intel_1x16 ..................................................................... 215 FSDev_NOR_SST39 ........................................................................... 216 FSDev_NOR_STM25 .......................................................................... 216 FSDev_NOR_SST25 ........................................................................... 217 Chapter 15 15-1 15-2 MSC Driver ......................................................................................... 219 Files and Directories .......................................................................... 219 Using the MSC Driver ........................................................................ 220 Appendix A A-1 A-1-1 A-1-2 A-1-3 A-1-4 A-1-5 A-2 A-2-1 A-2-2 A-2-3 A-2-4 A-2-5 A-2-6 A-2-7 A-2-8 A-2-9 A-2-10 A-2-11 A-2-12 A-2-13 A-2-14 A-2-15 C/FS API Reference ......................................................................... 223 General File System Functions .......................................................... 225 FS_DevDrvAdd() ................................................................................. 226 FS_Init() ............................................................................................... 227 FS_VersionGet() .................................................................................. 228 FS_WorkingDirGet() ............................................................................ 229 FS_WorkingDirSet() ............................................................................ 230 Posix API Functions ........................................................................... 231 fs_asctime_r() ..................................................................................... 234 fs_chdir() ............................................................................................. 235 fs_clearerr() ......................................................................................... 236 fs_closedir() ........................................................................................ 237 fs_ctime_r() ......................................................................................... 238 fs_fclose() ........................................................................................... 239 fs_feof() ............................................................................................... 240 fs_ferror() ............................................................................................ 241 fs_fflush() ............................................................................................ 242 fs_fgetpos() ......................................................................................... 243 fs_flockfile() ........................................................................................ 244 fs_fopen() ............................................................................................ 245 fs_fread() ............................................................................................. 246 fs_fseek() ............................................................................................ 247 fs_fsetpos() ......................................................................................... 249 7 600-uC-FS-001.book Page 8 Wednesday, October 10, 2012 12:03 PM Table of Contents A-2-16 A-2-17 A-2-18 A-2-19 A-2-20 A-2-21 A-2-22 A-2-23 A-2-24 A-2-25 A-2-26 A-2-27 A-2-28 A-2-29 A-2-30 A-2-31 A-2-32 A-3 A-3-1 A-3-2 A-3-3 A-3-4 A-3-5 A-3-6 A-3-7 A-3-8 A-3-9 A-3-10 A-3-11 A-3-12 A-3-13 A-3-14 A-3-15 A-3-16 A-4 A-4-1 A-4-2 A-4-3 8 fs_ftell() ............................................................................................... 250 fs_ftruncate() ...................................................................................... 251 fs_ftrylockfile() .................................................................................... 252 fs_funlockfile() .................................................................................... 253 fs_fwrite() ............................................................................................ 254 fs_getcwd() ......................................................................................... 255 fs_localtime_r() ................................................................................... 256 fs_mkdir() ............................................................................................ 257 fs_mktime() ......................................................................................... 258 fs_opendir() ......................................................................................... 259 fs_readdir_r() ....................................................................................... 260 fs_remove() ......................................................................................... 261 fs_rename() ......................................................................................... 263 fs_rewind() .......................................................................................... 265 fs_rmdir() ............................................................................................. 266 fs_setbuf() ........................................................................................... 267 fs_setvbuf() ......................................................................................... 268 Device Functions ............................................................................... 270 FSDev_AccessLock() ......................................................................... 273 FSDev_AccessUnlock() ...................................................................... 274 FSDev_Close() .................................................................................... 275 FSDev_GetDevName() ....................................................................... 276 FSDev_GetDevCnt() ........................................................................... 277 FSDev_GetDevCntMax() .................................................................... 278 FSDev_GetNbrPartitions() .................................................................. 279 FSDev_Invalidate() ............................................................................. 280 FSDev_Open() .................................................................................... 281 FSDev_PartitionAdd() ......................................................................... 283 FSDev_PartitionFind() ........................................................................ 284 FSDev_PartitionInit() .......................................................................... 286 FSDev_Query() ................................................................................... 287 FSDev_Rd() ......................................................................................... 288 FSDev_Refresh() ................................................................................. 289 FSDev_Wr() ......................................................................................... 291 Directory Access Functions .............................................................. 292 FSDir_Close() ...................................................................................... 293 FSDir_IsOpen() ................................................................................... 294 FSDir_Open() ...................................................................................... 295 600-uC-FS-001.book Page 9 Wednesday, October 10, 2012 12:03 PM A-4-4 A-5 A-5-1 A-5-2 A-5-3 A-5-4 A-5-5 A-5-6 A-5-7 A-6 A-6-1 A-6-2 A-6-3 A-6-4 A-6-5 A-6-6 A-6-7 A-6-8 A-6-9 A-6-10 A-6-11 A-6-12 A-6-13 A-6-14 A-6-15 A-6-16 A-6-17 A-7 A-7-1 A-7-2 A-7-3 A-7-4 A-7-5 A-7-6 A-7-7 A-7-8 A-7-9 A-7-10 FSDir_Rd() .......................................................................................... 296 Entry Access Functions ..................................................................... 297 FSEntry_AttribSet() ............................................................................. 298 FSEntry_Copy() .................................................................................. 300 FSEntry_Create() ................................................................................ 302 FSEntry_Del() ...................................................................................... 304 FSEntry_Query() ................................................................................. 306 FSEntry_Rename() .............................................................................. 307 FSEntry_TimeSet() .............................................................................. 309 File Functions ..................................................................................... 311 FSFile_BufAssign() ............................................................................. 313 FSFile_BufFlush() ............................................................................... 315 FSFile_Close() ..................................................................................... 316 FSFile_ClrErr() .................................................................................... 317 FSFile_IsEOF() .................................................................................... 318 FSFile_IsErr() ...................................................................................... 319 FSFile_IsOpen() .................................................................................. 320 FSFile_LockAccept() .......................................................................... 321 FSFile_LockGet() ................................................................................ 322 FSFile_LockSet() ................................................................................ 323 FSFile_Open() ..................................................................................... 324 FSFile_PosGet() .................................................................................. 326 FSFile_PosSet() .................................................................................. 327 FSFile_Query() .................................................................................... 329 FSFile_Rd() ......................................................................................... 330 FSFile_Truncate() ................................................................................ 332 FSFile_Wr() ......................................................................................... 333 Volume Functions .............................................................................. 335 FSVol_Close() ..................................................................................... 337 FSVol_Fmt() ........................................................................................ 338 FSVol_GetDfltVolName() .................................................................... 340 FSVol_GetVolCnt() .............................................................................. 341 FSVol_GetVolCntMax() ....................................................................... 342 FSVol_GetVolName() .......................................................................... 343 FSVol_IsDflt() ...................................................................................... 344 FSVol_IsMounted() ............................................................................. 345 FSVol_LabelGet() ................................................................................ 346 FSVol_LabelSet() ................................................................................ 348 9 600-uC-FS-001.book Page 10 Wednesday, October 10, 2012 12:03 PM Table of Contents A-7-11 A-7-12 A-7-13 A-7-14 A-8 A-8-1 A-8-2 A-8-3 A-9 A-9-1 A-9-2 A-9-3 A-10 A-10-1 A-10-2 A-10-3 A-11 A-11-1 A-11-2 A-11-3 A-11-4 A-11-5 A-11-6 A-11-7 A-11-8 A-11-9 A-12 A-12-1 A-12-2 A-12-3 A-12-4 A-12-5 FSVol_Open() ...................................................................................... 350 FSVol_Query() ..................................................................................... 352 FSVol_Rd() .......................................................................................... 353 FSVol_Wr() .......................................................................................... 355 Volume Cache Functions ................................................................... 356 FSVol_CacheAssign() ......................................................................... 357 FSVol_CacheInvalidate () ................................................................... 359 FSVol_CacheFlush () .......................................................................... 360 SD/MMC Driver Functions ................................................................. 361 FSDev_SD_xxx_QuerySD() ................................................................ 362 FSDev_SD_xxx_RdCID() .................................................................... 364 FSDev_SD_xxx_RdCSD() ................................................................... 366 NAND Driver Functions ...................................................................... 368 FSDev_NAND_LowFmt() .................................................................... 369 FSDev_NAND_LowMount() ................................................................ 370 FSDev_NAND_LowUnmount() ........................................................... 372 NOR Driver Functions ........................................................................ 373 FSDev_NOR_LowFmt() ...................................................................... 374 FSDev_NOR_LowMount() .................................................................. 375 FSDev_NOR_LowUnmount() .............................................................. 376 FSDev_NOR_LowCompact() .............................................................. 377 FSDev_NOR_LowDefrag() .................................................................. 378 FSDev_NOR_PhyRd() ......................................................................... 379 FSDev_NOR_PhyWr() ......................................................................... 381 FSDev_NOR_PhyEraseBlk() ............................................................... 383 FSDev_NOR_PhyEraseChip() ............................................................ 385 FAT System Driver Functions ............................................................ 386 FS_FAT_JournalOpen() ....................................................................... 387 FS_FAT_JournalClose() ...................................................................... 388 FS_FAT_JournalStart() ........................................................................ 389 FS_FAT_JournalStop() ........................................................................ 390 FS_FAT_VolChk() ................................................................................ 391 Appendix B B-1 B-2 B-3 B-4 C/FS Error Codes ............................................................................. 393 System Error Codes ........................................................................... 393 Buffer Error Codes ............................................................................. 393 Cache Error Codes ............................................................................ 394 Device Error Codes ............................................................................ 394 10 600-uC-FS-001.book Page 11 Wednesday, October 10, 2012 12:03 PM B-5 B-6 B-7 B-8 B-9 B-10 B-11 B-12 B-13 B-14 B-15 Device Driver Error Codes ................................................................. 395 Directory Error Codes ........................................................................ 395 ECC Error Codes ................................................................................ 395 Entry Error Codes .............................................................................. 395 File Error Codes ................................................................................. 396 Name Error Codes ............................................................................. 397 Partition Error Codes ......................................................................... 397 Pools Error Codes .............................................................................. 397 File System Error Codes .................................................................... 398 Volume Error Codes ........................................................................... 398 OS Layer Error Codes ........................................................................ 399 Appendix C C-1 C-2 C-3 C-4 C-4-1 C-4-2 C-4-3 C-4-4 C-4-5 C-4-6 C-4-7 C-4-8 C-5 C-5-1 C-5-2 C-5-3 C-5-4 C-5-5 C-5-6 C-5-7 C-5-8 C-5-9 C-5-10 C-5-11 C-5-12 C/FS Porting Manual ........................................................................ 401 Date/Time Management .................................................................... 403 CPU Port ............................................................................................. 403 OS Kernel ........................................................................................... 404 Device Driver ...................................................................................... 412 NameGet() .......................................................................................... 414 Init() ..................................................................................................... 415 Open() ................................................................................................. 416 Close() ................................................................................................. 418 Rd() ..................................................................................................... 419 Wr() ...................................................................................................... 421 Query() ................................................................................................ 423 IO_Ctrl() ............................................................................................... 424 SD/MMC Cardmode BSP .................................................................. 425 FSDev_SD_Card_BSP_Open() ........................................................... 429 FSDev_SD_Card_BSP_Lock/Unlock() ............................................... 430 FSDev_SD_Card_BSP_CmdStart() .................................................... 431 FSDev_SD_Card_BSP_CmdWaitEnd() .............................................. 436 FSDev_SD_Card_BSP_CmdDataRd() ............................................... 440 FSDev_SD_Card_BSP_CmdDataWr() ................................................ 443 FSDev_SD_Card_BSP_GetBlkCntMax() ............................................ 446 FSDev_SD_Card_BSP_GetBusWidthMax() ....................................... 447 FSDev_SD_Card_BSP_SetBusWidth() .............................................. 448 FSDev_SD_Card_BSP_SetClkFreq() ................................................. 450 FSDev_SD_Card_BSP_SetTimeoutData() ......................................... 451 FSDev_SD_Card_BSP_SetTimeoutResp() ........................................ 452 11 600-uC-FS-001.book Page 12 Wednesday, October 10, 2012 12:03 PM Table of Contents C-6 C-7 C-7-1 C-7-2 C-7-3 C-7-4 C-7-5 C-7-6 C-7-7 C-8 C-9 C-9-1 C-9-2 C-9-3 C-9-4 C-9-5 C-9-6 C-10 C-10-1 C-10-2 C-10-3 C-10-4 C-10-5 C-10-6 C-11 SD/MMC SPI mode BSP .................................................................... 452 SPI BSP .............................................................................................. 453 Open() ................................................................................................. 457 Close() ................................................................................................. 459 Lock() / Unlock() ................................................................................. 460 Rd() ..................................................................................................... 461 Wr() ...................................................................................................... 462 ChipSelEn() /ChipSelDis() .................................................................. 463 SetClkFreq() ........................................................................................ 464 NAND Flash Physical-Layer Driver .................................................... 464 NOR Flash Physical-Layer Driver ...................................................... 464 Open() ................................................................................................. 467 Close() ................................................................................................. 468 Rd() ..................................................................................................... 469 Wr() ...................................................................................................... 470 EraseBlk() ........................................................................................... 471 IO_Ctrl() ............................................................................................... 472 NOR Flash BSP .................................................................................. 473 FSDev_NOR_BSP_Open() .................................................................. 474 FSDev_NOR_BSP_Close() ................................................................. 475 FSDev_NOR_BSP_Rd_XX() ................................................................ 476 FSDev_NOR_BSP_RdWord_XX() ....................................................... 477 FSDev_NOR_BSP_WrWord_XX() ....................................................... 478 FSDev_NOR_BSP_WaitWhileBusy() .................................................. 479 NOR Flash SPI BSP ........................................................................... 480 Appendix D D-1 D-2 D-3 D-4 D-5 D-6 D-7 D-8 D-9 C/FS Types and Structures ............................................................. 481 FS_CFG .............................................................................................. 482 FS_DEV_INFO ..................................................................................... 484 FS_DEV_NOR_CFG ............................................................................ 485 FS_DEV_RAM_CFG ............................................................................ 488 FS_DIR_ENTRY (struct fs_dirent) ...................................................... 489 FS_ENTRY_INFO ................................................................................ 490 FS_FAT_SYS_CFG ............................................................................. 492 FS_PARTITION_ENTRY ..................................................................... 494 FS_VOL_INFO ..................................................................................... 495 12 600-uC-FS-001.book Page 13 Wednesday, October 10, 2012 12:03 PM Appendix E E-1 E-2 E-3 E-4 E-5 E-6 E-7 E-8 E-9 C/FS Configuration .......................................................................... 497 File System Configuration ................................................................. 498 Feature Inclusion Configuration ........................................................ 500 Name Restriction Configuration ........................................................ 503 Debug Configuration .......................................................................... 504 Argument Checking Configuration .................................................... 504 File System Counter Configuration ................................................... 505 FAT Configuration .............................................................................. 505 SD/MMC SPI Configuration ............................................................... 506 Trace Configuration ........................................................................... 507 Appendix F F-1 F-2 F-3 F-3-1 F-3-2 F-3-3 F-3-4 F-3-5 F-3-6 F-3-7 F-3-8 F-3-9 F-3-10 F-3-11 F-3-12 F-3-13 F-3-14 F-3-15 F-3-16 F-3-17 F-4 Shell Commands ................................................................................ 509 Files and Directories .......................................................................... 510 Using the Shell Commands ............................................................... 511 Commands ......................................................................................... 514 fs_cat .................................................................................................. 515 fs_cd ................................................................................................... 516 fs_cp ................................................................................................... 518 fs_date ................................................................................................ 519 fs_df .................................................................................................... 520 fs_ls ..................................................................................................... 521 fs_mkdir .............................................................................................. 522 fs_mkfs ............................................................................................... 523 fs_mount ............................................................................................. 524 fs_mv .................................................................................................. 525 fs_od ................................................................................................... 526 fs_pwd ................................................................................................ 527 fs_rm ................................................................................................... 528 fs_rmdir ............................................................................................... 529 fs_touch .............................................................................................. 530 fs_umount ........................................................................................... 531 fs_wc ................................................................................................... 532 Configuration ...................................................................................... 533 13 600-uC-FS-001.book Page 14 Wednesday, October 10, 2012 12:03 PM Table of Contents Appendix G Bibliography ....................................................................................... 535 Appendix H H-1 H-1-1 H-1-2 H-1-3 H-1-4 C/FS Licensing Policy ...................................................................... 537 C/FS Licensing ................................................................................. 537 C/FS Source Code ........................................................................... 537 C/FS Maintenance Renewal ............................................................ 538 C/FS Source Code Updates ............................................................ 538 C/FS Support ................................................................................... 538 14 600-uC-FS-001.book Page 15 Wednesday, October 10, 2012 12:03 PM Chapter 1 Introduction Files and directories are common abstractions, which we encounter daily when sending an e-mail attachment, downloading a new application or archiving old information. Those same abstractions may be leveraged in an embedded system for similar tasks or for unique ones. A device may serve web pages, play or record media (images, video or music) or log data. The file system software which performs such actions must meet the general expectations of an embedded environment--a limited code footprint, for instance--while still delivering good performance. 1-1 C/FS C/FS is a compact, reliable, high-performance file system. It offers full-featured file and directory access with flexible device and volume management including support for partitions. Source Code: C/FS is provided in ANSI-C source to licensees. The source code is written to an exacting coding standard that emphasizes cleanness and readability. Moreover, extensive comments pepper the code to elucidate its logic and describe global variables and functions. Where appropriate, the code directly references standards and supporting documents. Device Drivers: Device drivers are available for most common media including SD/MMC cards, NAND flash, NOR flash. Each of these is written with a clear, layered structure so that it can easily be ported to your hardware. The device driver structure is simple--basically just initialization, read and write functions--so that C/FS can easily be ported to a new medium. 15 600-uC-FS-001.book Page 16 Wednesday, October 10, 2012 12:03 PM Chapter 1 Devices and Volumes: Multiple media can be accessed simultaneously, including multiple instances of the same type of medium (since all drivers are re-entrant). DOS partitions are supported, so more than one volume can be located on a device. In addition, the logical device driver allows a single volume to span several (typically identical) devices, such as a bank of flash chips. FAT: All standard FAT variants and features are supported including FAT12/FAT16/FAT32 and long file names, which encompasses Unicode file names. Files can be up to 4-GB and volumes up to 8-TB (the standard maximum). An optional journaling module provides total power fail-safety to the FAT system driver. Application Programming Interface (API): C/FS provides two APIs for file and directory access. A proprietary API with parallel argument placement and meaningful return error codes is provided, with functions like FSFile_Wr(), FSFile_Rd() and FSFile_PosSet(). Alternatively, a standard POSIX-compatible API is provided, including functions like fs_fwrite(), fs_fread() and fs_fsetpos() that have the same arguments and return values as the POSIX functions fwrite(), fread() and fsetpos(). Scalable: The memory footprint of C/FS can be adjusted at compile-time based on the features you need and the desired level of run-time argument checking. For applications with limited RAM, features such as cache and read/write buffering can be disabled; for applications with sufficient RAM, these features can be enabled in order to gain better performance. Portable: C/FS was designed for resource-constrained embedded applications. Although C/FS can work on 8- and 16-bit processors, it will work best with 32- or 64-bit CPUs. RTOS: C/FS does not assume the presence of a RTOS kernel. However, if you are using a RTOS, a simple port layer is required (consisting of a few semaphores), in order to prevent simultaneous access to core structures from different tasks. If you are not using a RTOS, this port layer may consist of empty functions. 16 600-uC-FS-001.book Page 17 Wednesday, October 10, 2012 12:03 PM Typical Usages 1-2 TYPICAL USAGES Applications have sundry reasons for non-volatile storage. A subset require (or benefit from) organizing data into named files within a directory hierarchy on a volume--basically, from having a file system. Perhaps the most obvious expose the structure of information to the user, like products that store images, video or music that are transferred to or from a PC. A web interface poses a similar opportunity, since the URLs of pages and images fetched by the remote browser would resolve neatly to locations on a volume. Another typical use is data logging. A primary purpose of a device may be to collect data from its environment for later retrieval. If the information must persist across device reset events or will exceed the capacity of its RAM, some non-volatile memory is necessary. The benefit of a file system is the ability to organize that information logically, with a fitting directory structure, through a familiar API. A file system can also store programs. In a simple embedded CPU, the program is stored at a fixed location in a non-volatile memory (usually flash). If an application must support firmware updates, a file system may be a more convenient place, since the software handles the details of storing the program. The boot-loader, of course, would need to be able to load the application, but since that requires only read-only access, no imposing program is required. The ROM boot-loaders in some CPUs can check the root directory of a SD card for a binary in addition to the more usual locations such as external NAND or NOR flash. 1-3 WHY FAT? File Allocation Table (FAT) is a simple file system, widely supported across major OSs. While it has been supplanted as the format of hard drives in Windows PCs, removable media still use FAT because of its wide support. That is suitable for embedded systems, which would often be challenged to muster the resources for the modern file systems developed principally for large fixed disks. C/FS supports FAT because of the interoperability requirements of removable media, allowing that a storage medium be removed from an embedded device and connected to a PC. All variants and extensions are supported to specification. 17 600-uC-FS-001.book Page 18 Wednesday, October 10, 2012 12:03 PM Chapter 1 A notorious weakness of FAT (exacerbated by early Windows system drivers) is its non-fail safe architecture. Certain operations leave the file system in an inconsistent state, albeit briefly, which may corrupt the disk or force a disk check upon unexpected power failure. C/FS minimizes the problem by ordering modifications wisely. The problem is completely solved in an optional journaling module which logs information about pending changes so those can be resumed on start-up after a power failure. 1-4 CHAPTER CONTENTS Figure 1-1 shows the layout and flow of the book. This diagram should be useful to understand the relationship between chapters. The first (leftmost) column lists chapters that should be read in order to understand C/FS's structure. The chapters in the second column give greater detail about the application of C/FS. Each of the chapters in the third column examines a storage technology and its device driver. Finally, the fourth column lists the appendices, the topmost being the C/FS reference, configuration and porting manuals. Reference these sections regularly when designing a product using C/FS. (A) (1) (B) (2) (C) Introduction C/FS Architecture C/FS Directories and Files (3) (4) SD/MMC Driver Devices and Volumes (5) (6) Files (7) Directories (8) POSIX API FAT File System Device Drivers (9) C/FS Error Codes C/FS Porting Manual (11) (D) C/FS Types and Structures (12) (E) C/FS Configuration Manual (F) C/FS Shell Commands RAM Disk Driver Useful Information C/FS API Reference Manual (13) NAND Flash Driver (14) (10) NOR Flash Driver Mass Storage Class (MSC) Driver (15) (G) Bibliography Figure 1-1 C/FS book layout 18 600-uC-FS-001.book Page 19 Wednesday, October 10, 2012 12:03 PM Chapter Contents Chapter 1, "Introduction". This chapter. Chapter 2, "C/FS Architecture". This chapter contains a simplified block diagram of the various different C/FS modules and their relationships. The relationships are then explained. Chapter 3, "C/FS Directories and Files". This chapter explains the directory structure and files needed to build a C/FS-based application. Learn about the files that are needed, where they should be placed, which module does what, and more. Chapter 4, "Useful Information". In this chapter, you will learn the nomenclature used in C/FS to access files and folders and the resources needed to use C/FS in your application. Chapter 5, "Devices and Volumes". Every file and directory accessed with C/FS is a constituent of a volume (a collection of files and directories) on a device (a physical or logical sector-addressed entity). This chapter explains how devices and volumes are managed. Chapter 6, "Files". C/FS complements the POSIX API with its own file access API. This chapter explains this API. Chapter 7, "Directories". C/FS complements the POSIX API with its own directory access API. This chapter explains this API. Chapter 8, "POSIX API". The best-known API for accessing and managing files and directories is specified within the POSIX standard (IEEE Std 1003.1), which is based in part in the ISO C standard (ISO/IEC 9899). This chapter explains how to use this API and examines some of its pitfalls and shortcomings. Chapter 10, "FAT File System". This chapter details the low-level architecture of the FAT file system. Though the API of C/FS is file system agnostic, the file system type does affect performance, reliability and security, as explained here as well. Chapter 9, "Device Drivers". All hardware accesses are eventually performed by a device driver. This chapter describes the drivers available with C/FS and broadly profiles supported media types in terms of cost, performance and complexity. 19 600-uC-FS-001.book Page 20 Wednesday, October 10, 2012 12:03 PM Chapter 1 Chapter 11, "RAM Disk Driver". This chapter demonstrates the use of the simplest storage medium, the RAM disk. Chapter 12, "SD/MMC Drivers". SD and MMC cards are flash-based removable storage devices commonly used in consumer electronics. For embedded CPUs, a SD/MMC card is an appealing medium because of its simple and widely-supported physical interfaces (one choice is SPI). This chapter describes the interface and function of these devices. Chapter 13, "NAND Flash Driver". NAND flash is the first category of flash media. Write speeds are fast (compared to NOR flash), at the expense of slower read speeds and complexities such as bit-errors and page program limitations. This chapter describes the functions of these devices and the architecture of the supporting driver. Chapter 14, "NOR Flash Driver". NOR flash is the second category of flash media. They suffer slow write speeds, balanced with blazingly-fast read speeds. Importantly, they are not plagued by the complications of NAND flash, which simplifies interfacing with them. This chapter describes the function of these devices and the architecture of the supporting driver. Chapter 15, "MSC Driver". The now-common USB drive implements the Mass Storage Class (MSC) protocol, and a CPU with a USB host interface can access these devices with appropriate software. The MSC driver, discussed in this chapter, with C/USB-Host is just such appropriate software. Appendix A, "C/FS API Reference". The reference manual describes every API function. The arguments and return value of each function are given, supplemented by notes about its use and an example code listing. Appendix B, "C/FS Error Codes". This appendix provides a brief explanation of C/FS error codes defined in fs_err.h. Appendix C, "C/FS Porting Manual". The portability of C/FS relies upon ports to interface between its modules and the platform or environment. Most of the ports constitute the board support package (BSP), which is interposed between the file system suite (or driver) and hardware. The OS port adapts the software to a particularly OS kernel. The porting manual describes each port function. Appendix D, "C/FS Types and Structures". This appendix provides a reference to the C/FS types and structures. 20 600-uC-FS-001.book Page 21 Wednesday, October 10, 2012 12:03 PM Chapter Contents Appendix E, "C/FS Configuration". C/FS is configured via defines in a single configuration file, fs_cfg.h. The configuration manual specifies each define and the meaning of possible values. Appendix F, "Shell Commands". A familiar method of accessing a file system, at least to engineers and computer scientists, is the command line. In an embedded system, a UART is a port over which commands can be executed easily, even for debug purposes. A set of shell commands have been developed for C/FS that mirror the syntax of UNIX utilities, as described in this chapter. Appendix G, "Bibliography". Appendix H, "C/FS Licensing Policy". 21 600-uC-FS-001.book Page 22 Wednesday, October 10, 2012 12:03 PM Chapter 1 22 600-uC-FS-001.book Page 23 Wednesday, October 10, 2012 12:03 PM Chapter 2 C/FS Architecture C/FS was written from the ground up to be modular and easy to adapt to different CPUs (Central Processing Units), RTOSs (Real-Time Operating Systems), storage media and compilers. Figure 2-1 shows a simplified block diagram of the different C/FS modules and their relationships. Notice that all of the C/FS files start with `fs_'. This convention allows you to quickly identify which files belong to C/FS. Also note that all functions and global variables start with `FS', and all macros and #defines start with `FS_'. 23 600-uC-FS-001.book Page 24 Wednesday, October 10, 2012 12:03 PM Chapter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igure 2-1 C/FS architecture 24 600-uC-FS-001.book Page 25 Wednesday, October 10, 2012 12:03 PM Architecture Components 2-1 ARCHITECTURE COMPONENTS C/FS consists of a set of modular software components. It also requires a few external components (provided with the release) be compiled into the application and a few configuration and BSP files be adapted to the application. 2-1-1 YOUR APPLICATION Your application needs to provide configuration information to C/FS in the form of one C header file named fs_cfg.h. Some of the configuration data in fs_cfg.h consist of specifying whether certain features will be present. For example, LFN support, volume cache and file buffering are all enabled or disabled in this file. In all, there are about 30 #define to set. However, most of these can be set to their default values. 2-1-2 C-LIB (LIBRARIES) Because C/FS is designed to be used in safety critical applications, all `standard' library functions like strcpy(), memset(), etc., have been re-written to follow the same quality as the rest of the file system software. 2-1-3 POSIX API LAYER Your application interfaces to C/FS using the well-known stdio.h API (Application Programming Interface). Alternately, you can use C/FS's own file and directory interface functions. Basically, POSIX API layer is a layer of software that converts POSIX file access calls to C/FS file access calls. 25 600-uC-FS-001.book Page 26 Wednesday, October 10, 2012 12:03 PM Chapter 2 2-1-4 FS LAYER This layer contains most of the CPU-, RTOS- and compiler-independent code for C/FS. There are three categories of files in this section: 1 2 3 26 File system object-specific files: Devices (fs_dev.*) Directories (fs_dir.*) Entries (fs_entry.*) Files (fs_file.*) Partitions (fs_partition.*) Volumes (fs_vol.*) Support files: Buffer management (fs_buf.*) Cache management (fs_cache.*) Counter management (fs_ctr.h) File system driver (fs_sys.*) Unicode encoding support (fs_unicode.*) Utility functions (fs_util.*) Miscellaneous header files: Master C/FS header file (fs.h) Error codes (fs_err.h) Aggregate header file (fs_inc.h) Miscellaneous data types (fs_type.h) Miscellaneous definitions (fs_def.h) Configuration definitions (fs_cfg_fs.h) 600-uC-FS-001.book Page 27 Wednesday, October 10, 2012 12:03 PM Architecture Components 2-1-5 FILE SYSTEM DRIVER LAYER The file system driver layer understands the organization of a particular file system type, such as FAT. The current version of C/FS only supports FAT file systems. fs_fat*.* contains the file system driver which should be used for FAT12/FAT16/FAT32 disks with or without Long File Name (LFN) support. 2-1-6 DEVICE DRIVER LAYER The device driver layer understands about types of file system media (SD/MMC card, NOR flash, etc.). In order for the device drivers to be independent of your CPU, we use additional files to encapsulate such details as the access of registers, reading and writing to a data bus and setting clock rates. Each device driver is named according to the pattern fs_dev_<dev drv name>.c where <dev drv name> is the an identifier for the device driver. For example, the driver for SD/MMC cards using SPI mode is called fs_dev_sd_spi.c. Most device drivers require a BSP layer, with code for accessing registers, reading from or writing to a data bus, etc. This file is named according to the pattern fs_dev_<dev drv name>_bsp.c For example, fs_dev_sd_spi_bsp.c contains the BSP functions for the driver SD/MMC cards using SPI mode. 27 600-uC-FS-001.book Page 28 Wednesday, October 10, 2012 12:03 PM Chapter 2 2-1-7 C-CPU C/FS can work with either an 8, 16, 32 or even 64-bit CPU, but needs to have information about the CPU you are using. The C-CPU layer defines such things as the C data type corresponding to 16-bit and 32-bit variables, whether the CPU is little- or big-endian and, how interrupts are disabled and enabled on the CPU, etc. CPU specific files are found in the ...\uC-CPU directory and, in order to adapt C/FS to a different CPU, you would need to either modify the cpu*.* files or, create new ones based on the ones supplied in the uC-CPU directory. In general, it's much easier to modify existing files because you have a better chance of not forgetting anything. 2-1-8 RTOS LAYER C/FS does not require an RTOS. However, if C/FS is used with an RTOS, a set of functions must be implemented to prevent simultaneous access of devices and core C/FS structures by multiple tasks. C/FS is provided with a no-RTOS (which contains just empty functions), a C/OS-II and a C/OS-III interface. If you use a different RTOS, you can use the fs_os.* for C/OS-II as a template to interface to the RTOS of your choice. 28 600-uC-FS-001.book Page 29 Wednesday, October 10, 2012 12:03 PM Chapter 3 C/FS Directories and Files C/FS is fairly easy to use once you understand which source files are needed to make up a C/FS-based application. This chapter will discuss the modules available for C/FS and how everything fits together. Figure 3-1 shows the C/FS architecture and its relationship with the hardware. Memory devices may include actual media both removable (SD/MMC, CF cards) and fixed (NAND flash, NOR flash) as well as any controllers for such devices. Of course, your hardware would most likely contain other devices such as UARTs (Universal Asynchronous Receiver Transmitters), ADCs (Analog to Digital Converters) and Ethernet controller(s). Moreover, your application may include other middleware components like an OS kernel, networking (TCP/IP) stack or USB stack that may integrate with C/FS. A WindowsTM-based development platform is assumed. The directories and files make references to typical Windows-type directory structures. However, since C/FS is available in source form then it can certainly be used on Unix, Linux or other development platforms. This, of course, assumes that you are a valid C/FS licensee in order to obtain the source code. The names of the files are shown in upper case to make them `stand out'. The file names, however, are actually lower case. 29 600-uC-FS-001.book Page 30 Wednesday, October 10, 2012 12:03 PM Chapter 3 FS_CFG.H APP.C/H FS_APP.C/H Platform Independent FS.C/H FS_API.C/H FS_BUF.C/H FS_CACHE.C/H FS_CFG_FS.H FS_CTR.H FS_DEF.H FS_DEV.C/H FS_DIR.C/H FS_ENTRY.C/H Libraries FS_ERR.H FS_FILE.C/H FS_INC.H FS_PARTITION.C/H FS_SYS.C/H FS_TYPE.H FS_UNICODE.C/H FS_UTIL.C/H FS_VOL.C/H LIB_ASCII.C/H LIB_DEF.H LIB_MATH.C/H LIB_MEM.C/H LIB_STR.C/H CLK.C/H CLK_OS.C/H Filesystem Driver FS_FAT.C/H FS_FAT_DIR.C/H FS_FAT_ENTRY.C/H FS_FAT_FAT12.C/H FS_FAT_FAT16.C/H FS_FAT_FAT32.C/H FS_FAT_FILE.C/H FS_FAT_JOURNAL.C/H FS_FAT_LFN.C/H FS_FAT_SFN.C/H FS_FAT_TYPE.H ECC.H EDC_CRC.C/H ECC_HAMMING.C/H CRC_UTIL.C/H Device Drivers OS Specific FS_DEV_*.C/H FS_OS.C/H Platform Specific CPU Specific Board Support Package FS_DEV_*_BSP.C CPU.H CPU_A.ASM CPU_CORE.C/H BSP.C/H *.C *.H Figure 3-1 C/FS Architecture F3-1(1) 30 The application code consist of project or product files. For convenience, we simply called these app.c and app.h but your application can contain any number of files and they do not have to be called app.*. The application code is typically where you would find main(). 600-uC-FS-001.book Page 31 Wednesday, October 10, 2012 12:03 PM F3-1(2) Quite often, semiconductor manufacturers provide library functions in source form for accessing the peripherals on their CPU (Central Processing Unit) or MCU (Micro Controller Unit). These libraries are quite useful and often save valuable time. Since there is no naming convention for these files, *.c and *.h are assumed. F3-1(3) The Board Support Package (BSP) is code that you would typically write to interface to peripherals on your target board. For example you can have code to turn on and off LEDs (light emitting diodes), functions to turn on and off relays, and code to read switches and temperature sensors. F3-1(4) C/CPU is an abstraction of basic CPU-specific functionality. These files define functions to disable and enable interrupts, data types (e.g., CPU_INT08U, CPU_FP32) independent of the CPU and compiler and many more functions. F3-1(5) C/LIB consists of a group of source files to provide common functions for memory copy, string manipulation and character mapping. Some of the functions replace stdlib functions provided by the compiler. These are provided to ensure that they are fully portable from application to application and (most importantly) from compiler to compiler. F3-1(6) C/Clk is an independant clock/calendar management module, with source code for easily managing date and time in a product. C/FS uses the date and time information from C/Clk to update files and directories with the proper creation/modification/access time. F3-1(7) C/CRC is a stand-alone module for calculating checksums and error correction codes. This module is used by some of C/FS device drivers. F3-1(8) This is the C/FS platform-independent code, free of dependencies on CPU and memory device. This code is written in highly-portable ANSI C code. This code is only available to C/FS licensees. F3-1(9) This is the C/FS system driver for FAT file systems. This code is only available to C/FS licensees. 31 600-uC-FS-001.book Page 32 Wednesday, October 10, 2012 12:03 PM Chapter 3 F3-1(10) This is the collection of device drivers for C/FS. Each driver supports a certain device type, such as SD/MMC cards, NAND flash or NOR flash. Drivers are only available to C/FS licensees. F3-1(11) This is the C/FS code that is adapted to a specific platform. It consists of small code modules written for specific drivers called ports that must be adapted to the memory device controllers or peripherals integrated into or attached to the CPU. The requirements for these ports are described in Appendix C, Porting Manual. F3-1(12) C/FS does not require an RTOS. However, if C/FS is used with an RTOS, a set of functions must be implemented to prevent simultaneous access of devices and core C/FS structures by multiple tasks. F3-1(13) This C/FS configuration file defines which C/FS features (fs_cfg.h) are included in the application. 3-1 APPLICATION CODE When Micrim provides you with example projects, we typically place those in a directory structure as shown below. Of course, you can use whatever directory structure suits your project/product. \Micrium \Software \EvalBoards \<manufacturer> \<board name> \<compiler> \<project name> \*.* \Micrium This is where we place all software components and projects provided by Micrim. This directory generally starts from the root directory of your computer. 32 600-uC-FS-001.book Page 33 Wednesday, October 10, 2012 12:03 PM Application Code \Software This sub-directory contains all the software components and projects. \EvalBoards This sub-directory contains all the projects related to the evaluation boards supported by Micrim. \<manufacturer> Is the name of the manufacturer of the evaluation board. The `<' and `>' are not part of the actual name. \<board name> This is the name of the evaluation board. A board from Micrim will typically be called uC-Eval-xxxx where `xxxx' will represent the CPU or MCU used on the evaluation board. The `<' and `>' are not part of the actual name. \<compiler> This is the name of the compiler or compiler manufacturer used to build the code for the evaluation board. The `<' and `>' are not part of the actual name. \<project name> This is the name of the project that will be demonstrated. For example a simple C/FS project might have a project name of `FS-Ex1'. The `-Ex1' represents a project containing only C/FS. A project name of FS-Probe-Ex1 would represent a project containing C/FS as well as C/Probe. The `<' and `>' are not part of the actual name. \*.* These are the source files for the project/product. You are certainly welcomed to call the main files APP*.* for your own projects but you don't have to. This directory also contains the configuration file FS_CFG.H and other files as needed by the project. 33 600-uC-FS-001.book Page 34 Wednesday, October 10, 2012 12:03 PM Chapter 3 3-2 CPU As shown below is the directory where we place semiconductor manufacturer peripheral interface source files. Of course, you can use whatever directory structure suits your project/product. \Micrium \Software \CPU \<manufacturer> \<architecture> \*.* \Micrium This is where we place all software components and projects provided by Micrim. \Software This sub-directory contains all the software components and projects. \CPU This sub-directory is always called CPU. \<manufacturer> Is the name of the semiconductor manufacturer who provided the peripheral library. The `<' and `>' are not part of the actual name. \<architecture> This is the name of the specific library and is generally associated with a CPU name or an architecture. \*.* These are the library source files. The names of the files are determined by the semiconductor manufacturer. 34 600-uC-FS-001.book Page 35 Wednesday, October 10, 2012 12:03 PM Board Support Package (BSP) 3-3 BOARD SUPPORT PACKAGE (BSP) The BSP is generally found with the evaluation or target board because the BSP is specific to that board. In fact, if well written, the BSP should be used for multiple projects. \Micrium \Software \EvalBoards \<manufacturer> \<board name> \<compiler> \BSP \*.* \Micrium This is where we place all software components and projects provided by Micrim. \Software This sub-directory contains all the software components and projects. \EvalBoards This sub-directory contains all the projects related to evaluation boards. \<manufacturer> Is the name of the manufacturer of the evaluation board. The `<' and `>' are not part of the actual name. \<board name> This is the name of the evaluation board. A board from Micrim will typically be called uC Eval xxxx where `xxxx' will be the name of the CPU or MCU used on the evaluation board. The `<' and `>' are not part of the actual name. \<compiler> This is the name of the compiler or compiler manufacturer used to build the code for the evaluation board. The `<' and `>' are not part of the actual name. \BSP This directory is always called BSP. 35 600-uC-FS-001.book Page 36 Wednesday, October 10, 2012 12:03 PM Chapter 3 \*.* These are the source files of the BSP. Typically all the file names start with BSP_ but they don't have to. It's thus typical to find bsp.c and bsp.h in this directory. Again, the BSP code should contain functions such as LED control functions, initialization of timers, interface to Ethernet controllers and more. 3-4 C/CPU, CPU SPECIFIC SOURCE CODE C/CPU consists of files that encapsulate common CPU-specific functionality as well as CPU- and compiler-specific data types. \Micrium \Software \uC-CPU \cpu_core.c \cpu_core.h \cpu_def.h \Cfg\Template \cpu_cfg.h \<architecture> \<compiler> \cpu.h \cpu_a.asm \cpu_c.c \Micrium This directory contains all software components and projects provided by Micrim. \Software This sub-directory contains all the software components and projects. \uC-CPU This is the main C/CPU directory. 36 600-uC-FS-001.book Page 37 Wednesday, October 10, 2012 12:03 PM C/CPU, CPU Specific Source Code cpu_core.c contains C code that is common to all CPU architectures. Specifically, this file contains functions to measure the interrupt disable time of the CPU_CRITICAL_ENTER() and CPU_CRITICAL_EXIT() macros, a function that emulates a count leading zeros instruction and a few other functions. cpu_core.h contains the function prototypes of the functions provided in cpu_core.c as well as allocation of the variables used by this module to measure interrupt disable time. cpu_def.h contains miscellaneous #define constants used by the C/CPU module. \Cfg\Template This directory contains a configuration template file (cpu_cfg.h) that you will need to copy to your application directory in order to configure the C/CPU module based on your application requirements. cpu_cfg.h determines whether you will enable measurement of the interrupt disable time, whether your CPU implements a count leading zeros instruction in assembly language or whether it will need to be emulated in C and more. \<architecture> This is the name of the CPU architecture for which C/CPU was ported to. The `<' and `>' are not part of the actual name. \<compiler> This is the name of the compiler or compiler manufacturer used to build the code for the C/CPU port. The `<' and `>' are not part of the actual name. The files in this directory contain the C/CPU port. cpu.h contains type definitions to make C/FS and other modules independent of the CPU and compiler word sizes. Specifically, you will find the declaration of the CPU_INT16U, CPU_INT32U, CPU_FP32 and many other data types. Also, this file specifies whether the CPU is a big- or little-endian machine and contains function prototypes for functions that are specific to the CPU architecture and more. 37 600-uC-FS-001.book Page 38 Wednesday, October 10, 2012 12:03 PM Chapter 3 cpu_a.asm contains the assembly language functions to implement the code to disable and enable CPU interrupts, count leading zeros (if the CPU supports that instruction) and other CPU specific functions that can only be written in assembly language. This file could also contain code to enable caches, setup MPUs and MMU and more. The functions provided in this file are accessible from C. cpu_c.c contains C code of functions that are specific to the specific CPU architecture but written in C for portability. As a general rule, if a function can be written in C then it should, unless there are significant performance benefits by writing it in assembly language. 3-5 C/LIB, PORTABLE LIBRARY FUNCTIONS C/LIB consists of library functions that are meant to be highly portable and not tied to any specific compiler. This was done to facilitate third party certification of Micrim products. \Micrium \Software \uC-LIB \lib_ascii.c \lib_ascii.h \lib_def.h \lib_math.c \lib_math.h \lib_mem.c \lib_mem.h \lib_str.c \lib_str.h \Cfg\Template \lib_cfg.h \Ports \<architecture> \<compiler> \lib_mem_a.asm \Micrium This directory contains all software components and projects provided by Micrim. 38 600-uC-FS-001.book Page 39 Wednesday, October 10, 2012 12:03 PM C/Clk, Time/Calendar Management \Software This sub-directory contains all the software components and projects. \uC-LIB This is the main C/LIB directory. \Cfg\Template This directory contains a configuration template file (lib_cfg.h) that must be copied to the application directory to configure the C/LIB module based on application requirements. lib_cfg.h determines whether to enable assembly-language optimization (assuming there is an assembly-language file for the processor, i.e. lib_mem_a.asm) and a few other #defines. 3-6 C/CLK, TIME/CALENDAR MANAGEMENT C/Clk consists of functions that are meant to centralize time management in one independant module. This way, the same time info can be easily shared across all Micrium products. \Micrium \Software \uC-Clk \Cfg \Template \clk_cfg.h \OS \<rtos_name> \clk_os.c \Source \clk.c \clk.h \Micrium This directory contains all software components and projects provided by Micrim. 39 600-uC-FS-001.book Page 40 Wednesday, October 10, 2012 12:03 PM Chapter 3 \Software This sub-directory contains all the software components and projects. \uC-Clk This is the main C/Clk directory. \Cfg\Template This directory contains a configuration template file (clk_cfg.h) that must be copied to the application directory to configure the C/Clk module based on application requirements. clk_cfg.h determines whether clock will be managed by the RTOS or in your application. A few other #defines are used to enable/disable some features of C/Clk and to configure some parameteres, like the clock frequency. \OS This is the main OS directory. \<rtos_name> This is the directory that contains the file to perform RTOS abstraction. Note that the file for the selected RTOS abstraction layer must always be named clk_os.c. C/Clk has been tested with C/OS-II, C/OS-III and the RTOS layer files for these RTOS are found in the following directories: \Micrium\Software\uC-Clk\OS\uCOS-II\clk_os.c \Micrium\Software\uC-Clk\OS\uCOS-III\clk_os.c \Source This directory contains the CPU-independant source code for C/Clk. All file in this directory should be included in the build (assuming the presence of the source code). Features that are not required will be compiled out based on the value of #define constants in clk_cfg.h. 40 600-uC-FS-001.book Page 41 Wednesday, October 10, 2012 12:03 PM C/CRC, Checksums and Error Correction Codes 3-7 C/CRC, CHECKSUMS AND ERROR CORRECTION CODES C/CRC consists of functions to compute different error detection and correction codes. The functions are speed-optimized to avoid the important impact on performances that these CPU-intensive calcutions may present. \Micrium \Software \uC-CRC \Cfg \Template \crc_cfg.h \Ports \<architecture> \<compiler> \ecc_hamming_a.asm \edc_crc_a.asm \Source \edc_crc.h \edc_crc.c \ecc_hamming.h \ecc_hamming.c \ecc.h \crc_util.h \crc_util.c \Micrium This directory contains all software components and projects provided by Micrim. \Software This sub-directory contains all the software components and projects. \uC-CRC This is the main C/CRC directory. \Cfg\Template This directory contains a configuration template file (crc_cfg.h) that must be copied to the application directory to configure the C/CRC module based on application requirements. 41 600-uC-FS-001.book Page 42 Wednesday, October 10, 2012 12:03 PM Chapter 3 crc_cfg.h determines whether to enable assembly-language optimization (assuming there is an assembly-language file for the processor) and a few other #defines. \<architecture> The name of the CPU architecture that C/CRC was ported to. The `<' and `>' are not part of the actual name. \<compiler> The name of the compiler or compiler manufacturer used to build code for the C/CRC port. The `<' and `>' are not part of the actual name. ecc_hamming_a.asm contains the assembly language functions to optimize the calculation speed of Hamming code. edc_crc_a.asm contains the assembly language functions to optimize the calculation speed of CRC (cyclic redundancy checks). \Source This is the directory that contains all the CPU independent source code files. of C/CRC. 3-8 C/FS PLATFORM-INDEPENDENT SOURCE CODE The files in these directories are available to C/FS licensees (see Appendix H, Licensing Policy). \Micrium \Software \uC-FS \APP\Template \fs_app.c \fs_app.h \Cfg\Template \fs_cfg.h \OS\Template \fs_os.c \fs_os.h 42 600-uC-FS-001.book Page 43 Wednesday, October 10, 2012 12:03 PM C/FS Platform-Independent Source Code \Source \fs_c \fs.h \fs_api.c \fs_api.h \fs_buf.c \fs_buf.h \fs_cache.c \fs_cache.h \fs_cfg_fs.h \fs_ctr.h \fs_def.h \fs_dev.c \fs_dev.h \fs_dir.c \fs_dir.h \fs_entry.c \fs_entry.h \fs_err.h \fs_file.c \fs_file.h \fs_inc.h \fs_partition.c \fs_partition.h \fs_sys.c \fs_sys.h \fs_type.h \fs_unicode.c \fs_unicode.h \fs_util.c \fs_util.h \fs_vol.c \fs_vol.h \Micrium This is where we place all software components and projects provided by Micrim. 43 600-uC-FS-001.book Page 44 Wednesday, October 10, 2012 12:03 PM Chapter 3 \Software This sub-directory contains all the software components and projects. \uC-FS This is the main C/FS directory. \APP\Template This directory contains a template of the code for initializing the file system. \Cfg\Template This directory contains a configuration template file (lib_cfg.h) that is required to be copied to the application directory to configure the C/FS module based on application requirements. fs_cfg.h specifies which features of C/FS you want in your application. If C/FS is provided in linkable object code format then this file will be provided to show you what features are available in the object file. See Appendix B, C/FS Configuration Manual. \Source This directory contains the platform-independent source code for C/FS. All the files in this directory should be included in your build (assuming you have the source code). Features that you don't want will be compiled out based on the value of #define constants in fs_cfg.h. fs.c/h contains core functionality for C/FS including FS_Init() (called to initialize C/FS) and FS_WorkingDirSet()/FS_WorkingDirGet() (used to get and set the working directory). fs_api.c/h contains the code for the POSIX-compatible API. See Chapter x, API for details about the POSIX-compatible API. fs_buf.c/h contains the code for the buffer management (used internally by C/FS). fs_dev.c/h contains code for device management. See Chapter x, Devices for details about devices. 44 600-uC-FS-001.book Page 45 Wednesday, October 10, 2012 12:03 PM C/FS FAT Filesystem Source Code fs_dir.c/h contains code for directory access. See Chapter x, Directories for details about directory access. fs_entry.c/h contains code for entry access. See Chapter x, Entries for details about entry access. fs_file.c/h contains code for file access. See Chapter x, Files for details about file access. fs_inc.h is a master include file that includes all fs_sys.c/h contains the code for system driver management (used internally by C/FS). fs_unicode.c/h contains the code for handling Unicode strings (used internally by C/FS). 3-9 C/FS FAT FILESYSTEM SOURCE CODE The files in these directories are available to C/FS licensees (see Appendix H, Licensing Policy). \Micrium \Software \uC-FS \FAT \fs_fat.c \fs_fat.h \fs_fat_dir.c \fs_fat_dir.h \fs_fat_entry.c \fs_fat_entry.h \fs_fat_fat12.c \fs_fat_fat12.h \fs_fat_fat16.c \fs_fat_fat16.h \fs_fat_fat32.c 45 600-uC-FS-001.book Page 46 Wednesday, October 10, 2012 12:03 PM Chapter 3 \fs_fat_fat32.h \fs_fat_file.c \fs_fat_file.h \fs_fat_journal.c \fs_fat_journal.h \fs_fat_lfn.c \fs_fat_lfn.h \fs_fat_sfn.c \fs_fat_sfn.h \fs_fat_type.h \Micrium This is where we place all software components and projects provided by Micrim. \Software This sub-directory contains all the software components and projects. \uC-FS This is the main C/FS directory. \FAT This directory contains the FAT system driver for C/FS. All the files in this directory should be included in your build (assuming you have the source code). 3-10 C/FS MEMORY DEVICE DRIVERS These files are generic drivers to use with differenty memory devices. \Micrium \Software \uC-FS \Dev \MSC \fs_dev_msc.c \fs_dev_msc.h \NAND 46 600-uC-FS-001.book Page 47 Wednesday, October 10, 2012 12:03 PM C/FS Memory Device Drivers \fs_dev_nand.c \fs_dev_nand.h \Ctrlr \fs_dev_nand_ctrlr_gen.c \fs_dev_nand_ctrlr_gen.h \fs_dev_nand_ctrlr_gen_soft_ecc.c \fs_dev_nand_ctrlr_gen_soft_ecc.h \fs_dev_nand_ctrlr_gen_micron_ecc.c \fs_dev_nand_ctrlr_gen_micron_ecc.h \Part \fs_dev_nand_part_static.c \fs_dev_nand_part_static.h \fs_dev_nand_part_onfi.c \fs_dev_nand_part_onfi.h \Cfg\Template fs_dev_nand_cfg.h \BSP\Template \fs_dev_nand_ctrlr_gen_bsp.c \NOR \fs_dev_nor.c \fs_dev_nor.h \PHY \fs_dev_nor_amd_1x08.c \fs_dev_nor_amd_1x08.h \fs_dev_nor_amd_1x16.c \fs_dev_nor_amd_1x16.h \fs_dev_nor_intel.c \fs_dev_nor_intel.h \fs_dev_nor_sst25.c \fs_dev_nor_sst25.h \fs_dev_nor_sst39.c \fs_dev_nor_sst39.h \fs_dev_nor_stm25.c \fs_dev_nor_stm25.h \fs_dev_nor_stm29_1x08.c \fs_dev_nor_stm29_1x08.h \fs_dev_nor_stm29_1x16.c \fs_dev_nor_stm29_1x16.h 47 600-uC-FS-001.book Page 48 Wednesday, October 10, 2012 12:03 PM Chapter 3 \Template \fs_dev_nor_template.c \fs_dev_nor_template.h \BSP\Template \fs_dev_nor_bsp.c \BSP\Template (SPI GPIO) \fs_dev_nor_bsp.c \BSP\Template (SPI) \fs_dev_nor_bsp.c \RAMDisk \fs_dev_ram.c \fs_dev_ram.h \SD \fs_dev_sd.c \fs_dev_sd.h \Card \fs_dev_sd_card.c \fs_dev_sd_card.h \BSP\Template \fs_dev_sd_card_bsp.c \SPI \fs_dev_sd_spi.c \fs_dev_sd_spi.h \BSP\Template \fs_dev_sd_spi.bsp.c \Template \fs_dev_template.c \fs_dev_template.h \Micrium This directory contains all software components and projects provided by Micrim. \Software This sub-directory contains all the software components and projects. \uC-FS This is the main C/FS directory. 48 600-uC-FS-001.book Page 49 Wednesday, October 10, 2012 12:03 PM C/FS Memory Device Drivers \Dev This is where you will find the device driver files for the storage devices you are planning on using. \MSC This directory contains the MSC (Mass Storage Class - USB drives) driver files. fs_dev_msc.* are device driver for MSC devices. This driver is designed to work with C/USB host stack. For more details on this driver, please refer to Chapter 15, "MSC Driver" on page 219. \NAND This directory contains the NAND driver files. fs_dev_nand.* are the device driver for NAND devices. These files require a set of controller-layer functions (defined in a file named fs_dev_nand_ctrlr_<type>.*) as well as BSP functions specific to particular hardware and associated with chosen controller-layer (to be defined in a file named fs_dev_nand_ctrlr_<type>_bsp.c). Note that in the case of the "generic" controller-layer implementation, some controller extensions files (defined in files named fs_dev_nand_ctrlr_<ext_name>.*) may also be required. For more details on this driver, please refer to Chapter 13, "NAND Flash Driver" on page 159. \NOR This directory contains the NOR driver files. fs_dev_nor.* are the device driver for NOR devices. These files require a set of physical-layer functions (defined in a file name fs_dev_nor_<physical type>.*) as well as BSP functions (to be defined in a file named fs_dev_nor_bsp.c) to work with a particular hardware setup. For more details on this driver, please refer to Chapter 14, "NOR Flash Driver" on page 199. 49 600-uC-FS-001.book Page 50 Wednesday, October 10, 2012 12:03 PM Chapter 3 \RAMDisk This directory contains the RAM disk driver files. fs_dev_ramdisk.* constitue the RAM disk driver. For more details on this driver, please refer to Chapter 11, "RAM Disk Driver" on page 131. \SD This directory contains the SD/MMC driver files. fs_dev_sd.* are device driver for SD devices. Theses files require to be used with either the fs_dev_sd_spi.* (for SPI/one-wire mode) or fs_dev_sd_card.* (for Card/4-wires mode) files. These files require a set of BSP functions to be defined in a file named either fs_dev_sd_spi_bsp.c or fs_dev_sd_card_bsp.c to work with a particular hardware setup. For more details on this driver, please refer to Chapter 12, "SD/MMC Drivers" on page 135. 3-11 C/FS PLATFORM-SPECIFIC SOURCE CODE These files are provided by the C/FS device driver developer. See Chapter 17, Porting C/FS. However, the C/FS source code is delivered with port examples. \Micrium \Software \uC-FS \Examples \BSP \Dev <memory type> <manufacturer> <board name> \fs_dev_<memory type>_bsp.c \Micrium This directory contains all software components and projects provided by Micrim. 50 600-uC-FS-001.book Page 51 Wednesday, October 10, 2012 12:03 PM C/FS OS Abstraction Layer \Software This sub-directory contains all the software components and projects. \uC-FS This is the main C/FS directory. \Examples This is where you will find the device driver BSP example files. \Dev\<memory type> This is where you will find the examples BSP for one memory type. The `<' and `>' are not part of the actual name. The memory types supported by C/FS are the following: NAND, NOR, SD\CARD, SD\SPI. \<manufacturer> The name of the manufacturer of the evaluation board. The `<' and `>' are not part of the actual name. 3-12 C/FS OS ABSTRACTION LAYER This directory contains the RTOS abstraction layer which allows the use of C/FS with nearly any commercial of in-house RTOS, or without any RTOS at all. The abstraction layer for the selected RTOS is placed in a sub-directory under OS as follows: \Micrium \Software \uC-FS \OS \<rtos_name> \fs_os.c \fs_os.h \Micrium This directory contains all software components and projects provided by Micrim. \Software This sub-directory contains all the software components and projects. 51 600-uC-FS-001.book Page 52 Wednesday, October 10, 2012 12:03 PM Chapter 3 \uC-FS This is the main C/FS directory. \OS This is the main OS directory. \<rtos_name> This is the directory that contains the files to perform RTOS abstraction. Note that files for the selected RTOS abstraction layer must always be named fs_os.*. C/FS has been tested with C/OS-II, C/OS-III and without an RTOS. The RTOS layer files are found in the following directories: \Micrium\Software\uC-Clk\OS\None\fs_os.* \Micrium\Software\uC-Clk\OS\Template\fs_os.* \Micrium\Software\uC-Clk\OS\uCOS-II\fs_os.* \Micrium\Software\uC-Clk\OS\uCOS-III\fs_os.* 3-13 SUMMARY Below is a summary of all the directories and files involved in a C/FS-based project. The `<-Cfg' on the far right indicates that these files are typically copied into the application (i.e., project) directory and edited based on project requirements. \Micrium \Software \EvalBoards \<manufacturer> \<board name> \<compiler> \<project name> \app.c \app.h \other \BSP \bsp.c \bsp.h 52 600-uC-FS-001.book Page 53 Wednesday, October 10, 2012 12:03 PM Summary \other \CPU \<manufacturer> \<architecture> \*.* \uC-FS \APP\Template \fs_app.c \fs_app.h \CFG\Template \fs_cfg.h \Dev <-Cfg <-Cfg <-Cfg \MSC \fs_dev_msc.c \fs_dev_msc.h \NAND \fs_dev_nand.c \fs_dev_nand.h \Ctrlr \fs_dev_nand_ctrlr_gen.c \fs_dev_nand_ctrlr_gen.h \fs_dev_nand_ctrlr_gen_soft_ecc.c \fs_dev_nand_ctrlr_gen_soft_ecc.h \fs_dev_nand_ctrlr_gen_micron_ecc.c \fs_dev_nand_ctrlr_gen_micron_ecc.h \Part \fs_dev_nand_part_static.c \fs_dev_nand_part_static.h \fs_dev_nand_part_onfi.c \fs_dev_nand_part_onfi.h \Cfg\Template fs_dev_nand_cfg.h \BSP\Template \fs_dev_nand_ctrlr_gen_bsp.c \NOR \fs_dev_nor.c \fs_dev_nor.h 53 600-uC-FS-001.book Page 54 Wednesday, October 10, 2012 12:03 PM Chapter 3 \PHY \fs_dev_nor_amd_1x08.c \fs_dev_nor_amd_1x08.h \fs_dev_nor_amd_1x16.c \fs_dev_nor_amd_1x16.h \fs_dev_nor_intel.c \fs_dev_nor_intel.h \fs_dev_nor_sst25.c \fs_dev_nor_sst25.h \fs_dev_nor_sst39.c \fs_dev_nor_sst39.h \fs_dev_nor_stm25.c \fs_dev_nor_stm25.h \fs_dev_nor_stm29_1x08.c \fs_dev_nor_stm29_1x08.h \fs_dev_nor_stm29_1x16.c \fs_dev_nor_stm29_1x16.h \Template \fs_dev_nor_template.c \fs_dev_nor_template.h \BSP\<template> \fs_dev_nor_bsp.c \RAMDisk \fs_dev_ram.c \fs_dev_ram.h \SD \fs_dev_sd.c \fs_dev_sd.h \Card \fs_dev_sd_card.c \fs_dev_sd_card.h \BSP\Template \fs_dev_sd_card_bsp.c \SPI \fs_dev_sd_spi.c \fs_dev_sd_spi.h \BSP\Template \fs_dev_sd_spi.bsp.c 54 <-Cfg <-Cfg <-Cfg <-Cfg <-Cfg 600-uC-FS-001.book Page 55 Wednesday, October 10, 2012 12:03 PM Summary \Template \fs_dev_template.c \fs_dev_template.h \FAT \fs_fat.c \fs_fat.h \fs_fat_dir.c \fs_fat_dir.h \fs_fat_entry.c \fs_fat_entry.h \fs_fat_fat12.c \fs_fat_fat12.h \fs_fat_fat16.c \fs_fat_fat16.h \fs_fat_fat32.c \fs_fat_fat32.h \fs_fat_file.c \fs_fat_file.h \fs_fat_journal.c \fs_fat_journal.h \fs_fat_lfn.c \fs_fat_lfn.h \fs_fat_sfn.c \fs_fat_sfn.h \fs_fat_type.h \OS \<template> \fs_os.c \fs_os.h \<rtos_name> \fs_os.c \fs_os.h \Source \fs_c \fs.h \fs_api.c \fs_api.h \fs_buf.c <-Cfg <-Cfg <-Cfg <-Cfg 55 600-uC-FS-001.book Page 56 Wednesday, October 10, 2012 12:03 PM Chapter 3 \fs_buf.h \fs_cache.c \fs_cache.h \fs_cfg_fs.h \fs_ctr.h \fs_def.h \fs_dev.c \fs_dev.h \fs_dir.c \fs_dir.h \fs_entry.c \fs_entry.h \fs_err.h \fs_file.c \fs_file.h \fs_inc.h \fs_partition.c \fs_partition.h \fs_sys.c \fs_sys.h \fs_type.h \fs_unicode.c \fs_unicode.h \fs_util.c \fs_util.h \fs_vol.c \fs_vol.h \OS \<architecture> \<compiler> \os_cpu.h \os_cpu_a.asm \os_cpu_c.c \uC-CPU \cpu_core.c \cpu_core.h \cpu_def.h \Cfg\Template 56 600-uC-FS-001.book Page 57 Wednesday, October 10, 2012 12:03 PM Summary \cpu_cfg.h \<architecture> \<compiler> \cpu.h \cpu_a.asm \cpu_c.c \uC-Clk \Cfg \Template \clk_cfg.h \OS \<rtos_name> \clk_os.c \Source \clk.c \clk.h \uC-CRC \Cfg \Template \crc_cfg.h \Ports \<architecture> \<compiler> \ecc_hamming_a.asm \edc_crc_a.asm \Source \edc_crc.h \edc_crc.c \ecc_hamming.h \ecc_hamming.c \ecc.h \uC-LIB \lib_ascii.c \lib_ascii.h \lib_def.h \lib_math.c \lib_math.h \lib_mem.c <-Cfg <-Cfg <-Cfg 57 600-uC-FS-001.book Page 58 Wednesday, October 10, 2012 12:03 PM Chapter 3 \lib_mem.h \lib_str.c \lib_str.h \Cfg\Template \lib_cfg.h 58 <-Cfg 600-uC-FS-001.book Page 59 Wednesday, October 10, 2012 12:03 PM Chapter 4 Useful Information 4-1 NOMENCLATURE This manual uses a set of terms to consistently describe operation of C/FS and its hardware and software environment. The following is a small list of these terms, with definitions. A file system suite is software which can find and access files and directories. Using "file system suite" rather than "file system" eliminates any need for disambiguation among the second term's several meanings, which include "a system for organizing directories and files", "a collection of files and directories stored on a drive" and (commonly) the software which will be referred to as a file system suite. The term file system will always mean a collection of files and directories stored on a drive (or, in this document, volume). A device driver (or just driver) is a code module which allows the general-purpose file system suite to access a specific type of device. A device driver is registered with the file system suite. A device is an instance of a device type that is accessed using a device driver. An addressable area (typically of 512 bytes) on a device is a sector. A sector is the smallest area that (from the file system suite's point of view) can be atomically read or written. Several devices can use the same device driver. These are distinguished by each having a unique unit number. Consequently, <DEVICE NAME>:<UNIT NUMBER>: is a unique device identifier if all devices are required to have unique names. That requirement is enforced in this file system suite. 59 600-uC-FS-001.book Page 60 Wednesday, October 10, 2012 12:03 PM Chapter 4 A logical device is the combination of two or more separate devices. To form a logical device, the sector address spaces of the constituent devices are concatenated to form a single continuous address space. A device can be partitioned, or subdivided into one or more regions (called partitions) each consisting of a number of consecutive sectors. Typically, structures are written to the device instructing software as to the location and size of these partitions. This file system suite supports DOS partitions. A volume is a device or device partition with a file system. A device or device partition must go through a process called mounting to become a volume, which includes finding the file system and making it ready for use. The name by which a volume is addressed may also be called the volume's mount point. A device or volume may be formatted to create a new file system on the device. For disambiguation purposes, this process is also referred to as high-level formatting. The volume or device will automatically be mounted once formatting completes. For certain devices, it is either necessary or desirable to perform low-level formatting. This is the process of associating logical sector numbers with areas of the device. A file system driver is a code module which allows the general-purpose file system suite to access a specific type of file system. For example, this file system suite includes a FAT file system driver. FAT (File Allocation Table) is a common file system type, prevalent in removable media that must work with various OSs. It is named after its primary data structure, a large table that records what clusters of the disk are allocated. A cluster, or group of sectors, is the minimum data allocation unit of the FAT file system. 60 600-uC-FS-001.book Page 61 Wednesday, October 10, 2012 12:03 PM C/FS Device and Volume Names 4-2 C/FS DEVICE AND VOLUME NAMES Devices are specified by name. For example, a device can be opened: FSDev_Open("sd:0:", (void *)0, &err); In this case, "sd:0:" is the device name. It is a concatenation of: sd The name of the device driver : A single colon 0 The unit number : A final colon The unit number allows multiple devices of the same type; for example, there could be several SD/MMC devices connected to the CPU: "sd:0:", "sd:1", "sd:2"... The maximum length of a device name is FS_CFG_MAX_DEV_NAME_LEN; this must be at least three characters larger than the maximum length of a device driver name, FS_CFG_MAX_DEV_DRV_NAME_LEN. A device name (or device driver name) must not contain the characters: : \ / Volumes are also specified by name. For example, a volume can be formatted: FSVol_Fmt("vol:", (void *)0, &err); Here, "vol:" is the volume name. C/FS imposes no restrictions on these names, except that they must end with a colon (`:'), must be no more than FS_CFG_MAX_VOL_NAME_LEN characters long, and must not contain either of the characters `\' or `/': 61 600-uC-FS-001.book Page 62 Wednesday, October 10, 2012 12:03 PM Chapter 4 It is typical to name a volume the same as a device; for example, a volume may be opened: FSVol_Open("sd:0:" "sd:0:" (void *)0, &err); (a) (b) In this case, the name of the volume (a) is the same as the name as the device (b). When multiple volumes exist in the same application, the volume name should be prefixed to the file or directory path name: p_file = fs_fopen("sd:0:\\dir01\file01.txt", "w"); // File on SD card p_file = fs_fopen("ram:0:\\dir01\file01.txt", "w"); // File on RAM disk 4-3 C/FS FILE AND DIRECTORY NAMES AND PATHS Files and directories are identified by a path string; for example, a file can be opened: p_file = fs_fopen("\\test\\file001.txt", "w"); In this case, "\\test\\file001.txt" is the path string. An application specifies the path of a file or directory using either an absolute or a relative path. An absolute path is a character string which specifies a unique file, and follows the pattern: <vol_name>:<... Path ...><File> where <vol_name> is the name of the volume, identical to the string specified in FSVol_Open(). <... Path ...> is the file path, which must always begin and end with a `\'. <File> is the file (or leaf directory) name, including any extension. 62 600-uC-FS-001.book Page 63 Wednesday, October 10, 2012 12:03 PM C/FS File and Directory Names and Paths For example: p_file p_file p_file p_file p_file p_file = = = = = = fs_fopen("sd:0:\\file.txt", "w"); (a) fs_fopen("\\file.txt", "w"); (b) fs_fopen("sd:0:\\dir01\\file01.txt", "w"); (c) fs_opendir("sd:0:\\") (d) fs_opendir("\\") (e) fs_opendir("sd:0:\\dir01\\") (f) Which demonstrate (a) opening a file in the root directory of a specified volume; (b) opening a file in the root directory on a default volume; (c) opening a file in a non-root directory; (d) opening the root directory of a specified volume; (e) opening the root directory of the default volume; (f) opening a non-root directory. Relative paths can be used if working directories are enabled (FS_CFG_WORKING_DIR_EN is DEF_ENABLED -- see Appendix E on page 501). A relative path begins with neither a volume name nor a `\': <... Relative Path ...><File> where <... Relative Path ...> is the file path, which must not begin with a `\' but must end with a `\'. <File> is the file (or leaf directory) name, including any extension. Two special path components can be used. ".." moves the path to the parent directory. "." keeps the path in the same directory (basically, it does nothing). A relative path is appended to the current working directory of the calling task to form the absolute path of the file or directory. The working directory functions, fs_chdir() and fs_getcwd(), can be used to set and get the working directory. 63 600-uC-FS-001.book Page 64 Wednesday, October 10, 2012 12:03 PM Chapter 4 4-4 C/FS NAME LENGTHS The configuration constants FS_CFG_MAX_PATH_NAME_LEN, FS_CFG_MAX_FILE_NAME_LEN and FS_CFG_MAX_VOL_NAME_LEN in fs_cfg.h set the maximum length of path names, file names and volume names. The constant FS_CFG_MAX_FULL_NAME_LEN is defined in fs_cfg_fs.h to describe the maximum full name length. The path name begins with a path separator character and includes the file name; the file name is just the portion of the path name after the last (non-final) path separator character. The full name is composed of an explicit volume name (optional) and a path name; the maximum full name length can be calculated: FullNameLenmax = VolNameLenmax + PathNameLenmax Figure 2-3 demonstrates these definitions. IXOOQDPH SDWKQDPH P\YROXPH?0\'LU?0\'LU?0\'LU?P\BYHU\BYHU\BORQJBILOHBQDPHW[W SDUHQWQDPH ILOHQDPH YROXPHQDPH Figure 4-1 File, path and volume name lengths No maximum parent name length is defined, though one may be derived. The parent name must be short enough so that the path of a file in the directory would be valid. Strictly, the minimum file name length is 1 character, though some OSs may enforce larger values (eleven on some Windows systems), thereby decreasing the maximum parent name length. ParentNameLenmax = PathNameLenmax - FileNameLenmin - 1 The constants FS_CFG_MAX_DEV_DRV_NAME_LEN and FS_CFG_MAX_DEV_NAME_LEN in fs_cfg.h set the maximum length of device driver names and device names, as shown in Figure 2-4. The device name is between three and five characters longer than the device driver name, since the unit number (the integer between the colons of the device name) must be between 0 and 255. 64 600-uC-FS-001.book Page 65 Wednesday, October 10, 2012 12:03 PM Resource Usage GHYLFHQDPH VGFDUG GHYLFHGULYHUQDPH Figure 4-2 Device and device driver name lengths Each of the maximum name length configurations specifies the maximum string length without the NULL character. Consequently, a buffer which holds one of these names must be one character longer than the define value. 4-5 RESOURCE USAGE C/FS resource usage, of both ROM and RAM, depends heavily on application usage. How many (and which) interface functions are referenced determines the code and constant data space requirements. The greater the quantity of file system objects (buffers, files, directories, devices and volumes), the more RAM needed. Table 2-1 give the ROM usage for the file system core, plus additional components that can be included optionally, collected on IAR EWARM v6.40.1. The `core' ROM size includes all file system components and functions (except those itemized in the table); this is significantly larger than most installations because most applications use a fraction of the API. Component ROM, Thumb Mode ROM, ARM Mode High Size Opt High Speed Opt High Size Opt High Speed Opt Core* 43.1 kB 59.2 kB 66.5 kB 91.2 kB OS port (C/OS-III) 1.1 kB 1.4 kB 1.8 kB 2.2 kB LFN support 4.3 kB 5.2 kB 6.9 kB 8.2 kB Directories 1.7 kB 2.1 kB 2.7 kB 3.3 kB Volume check 0.9 kB 1.0 kB 1.4 kB 1.6 kB Partitions 1.3 kB 1.8 kB 2.2 kB 2.9 kB Table 4-1 ROM requirements 65 600-uC-FS-001.book Page 66 Wednesday, October 10, 2012 12:03 PM Chapter 4 *Includes code and data for all file system components and functions except those itemized in the table. RAM requirements are summarized in Table 2-2. The total depends on the number of each object allocated and the maximum sector size (set by values passed to FS_Init() in the file system configuration structure), and various name length configuration parameters (see Appendix E, "FS_CFG_MAX_PATH_NAME_LEN" on page 503). Item RAM (bytes) Core 932 Per device 44 + FS_CFG_MAX_DEV_NAME_LEN Per volume 152 + FS_CFG_MAX_VOL_NAME_LEN Per file 144 Per directory 100 Per buffer 36 + MaxSectorSize Per device driver 8 bytes Working directories ((FS_CFG_MAX_PATH_NAME_LEN * 2) + 8) * TaskCnt Table 4-2 RAM characteristics The number of tasks that use relative path names See also section 9-1-1 "Driver Characterization" on page 113 for ROM/RAM characteristics of file system suite drivers. 66 600-uC-FS-001.book Page 67 Wednesday, October 10, 2012 12:03 PM Chapter 5 Devices and Volumes To begin reading files from a medium or creating files on a medium, that medium (hereafter called a device) and the driver which will be used to access it must be registered with the file system. After that, a volume must be opened on that device (analogous to "mounting"). This operation will succeed if and only if the device responds and the file system control structures (for FAT, the Boot Parameter Block or BPB) are located and validated. In this manual, as in the design of C/FS, the terms `device' and `volume' have distinct, non-overlapping meanings. We define a `device' as a single physical or logical entity which contains a continuous sequence of addressable sectors. An SD/MMC card is a physical device. We define a `volume' as a collection of files and directories on a device. These definitions were selected so that multiple volumes could be opened on a device (as shown in Figure 5-1) without requiring ambiguous terminology. ide:0: ide:1: partition1 partition1 partition2 Device layer ide:0: ide:1a: ide:1b: Volume layer Figure 5-1 Device and volume architecture 67 600-uC-FS-001.book Page 68 Wednesday, October 10, 2012 12:03 PM Chapter 5 5-1 DEVICE OPERATIONS The ultimate purpose of a file system device is to hold data. Consequently, two major operations that can occur on a device are the reading and writing of individual sectors. Five additional operations can be performed which affect not just individual sectors, but the whole device: A device can be opened. During the opening of a device, it is initialized and its characteristics are determined (sector size, number of sectors, vendor). A device can be partitioned. Partitioning divides the final unallocated portion of the device into two parts, so that a volume could be located on each (see section 5-5 "Partitions" on page 73). A device can be low-level formatted. Some device must be low-level formatted before being used. A device can be (high-level) formatted. (High-level) formatting writes the control information for a file system to a device so that a volume on it can be mounted. Essentially, (high-level) formatting is the process of creating a volume on an empty device or partition. A device can be closed. During the closing of a device, it is uninitialized (if necessary) and associated structures are freed. These operations and the corresponding API functions are discussed in this section. For information about using device names, see section 4-2 "C/FS Device and Volume Names" on page 61. Function Description FSDev_AccessLock() Acquire exclusive access to a device. FSDev_AccessUnlock() Release exclusive access to a device. FSDev_Close() Remove device from file system. FSDev_GetNbrPartitions() Get number of partitions on a device. FSDev_Invalidate() Invalidate files and volumes open on a device. FSDev_IO_Ctrl() Perform device I/O control operation. 68 600-uC-FS-001.book Page 69 Wednesday, October 10, 2012 12:03 PM Using Devices Function Description FSDev_Open() Add device to file system. FSDev_PartitionAdd() Add partition to device. FSDev_PartitionFind() Find partition on device and get information about partition. FSDev_PartitionInit() Initialize partition on device. FSDev_Query() Get device information. FSDev_Rd() Read sector on device. FSDev_Refresh() Refresh device in file system. FSDev_Wr() Write sector on device. Table 5-1 Device API functions 5-2 USING DEVICES A device is opened with FSDev_Open(): FSDev_Open((CPU_CHAR *)"ide:0:", (void *) 0, (FS_ERR *)&err); <-- (a) device name <-- (b) pointer to configuration <-- (c) return error The parameters are the device name (a) and a pointer to a device driver-specific configuration structure (b). If a device driver requires no configuration structure (as the SD driver does not), the configuration structure (b) should be passed a NULL pointer. For other devices, like RAM disks, this must point to a valid structure. 69 600-uC-FS-001.book Page 70 Wednesday, October 10, 2012 12:03 PM Chapter 5 Device Object Pool Device closed (b) Closed (a) All references released Closing Device could not be initialized Opening Device not present Open Device removed or unresponsive t no e el vic lev d De ow atte l rm fo Device closed Low Format Valid Device inserted Present Device low level formatted Figure 5-2 Device state transition Prior to FSDev_Open() being called (a), software is ignorant of the presence, state or characteristics of the particular device. After all references to the device are released (b), this ignorance again prevails, and any buffers or structures are freed for later use. The return error code from this functions provides important information about the device state: If the return error code is FS_ERR_NONE, then the device is present, responsive and low-level formatted; basically, it is ready to use. If the return error code is FS_ERR_DEV_INVALID_LOW_FMT, then the device is present and responsive, but must be low-level formatted. The application should next call FSDev_NOR_LowFmt() for the NOR flash 70 600-uC-FS-001.book Page 71 Wednesday, October 10, 2012 12:03 PM Using Removable Devices If the return error code is FS_ERR_DEV_NOT_PRESENT, FS_ERR_DEV_IO or FS_ERR_DEV_TIMEOUT, the device is either not present or did not respond. This is an important consideration for removable devices. It is still registered with the file system suite, and the file system will attempt to re-open the device each time the application accesses it. If any other error code is returned, the device is not registered with the file system. The developer should examine the error code to determine the source of the error. 5-3 USING REMOVABLE DEVICES C/FS expects that any call to a function that accesses a removable device may fail, since the device may be removed, powered off or suddenly unresponsive. If C/FS detects such an event, the device will need to be refreshed or closed and re-opened. FSDev_Refresh() refreshes a device: chngd = FSDev_Refresh((CPU_CHAR *)"ide:0:", (FS_ERR *)&err); <-- (b) device name <-- (c) return error There are several cases to consider: If the return error is FS_ERR_NONE and the return value (a) is DEF_YES, then a new device (e.g., SD card) has been inserted. All files and directories that are open on volumes on the device must be closed and all volumes that are open on the device must be closed or refreshed. If the return error is FS_ERR_NONE and the return value (a) is DEF_NO, then the same device (e.g., SD card) is still inserted. The application can continue to access open files, directories and volumes. If the return error is neither FS_ERR_NONE nor FS_ERR_DEV_INVALID_LOW_FMT, then no functioning device is present. The device must be refreshed at a later time. A device can be refreshed explicitly with FSDev_Refresh(); however, refresh also happens automatically. If a volume access (e.g., FSVol_Fmt(), FSVol_Rd()), entry access (FSEntry_Create(), fs_remove()), file open (fs_fopen() or FSFile_Open()) or 71 600-uC-FS-001.book Page 72 Wednesday, October 10, 2012 12:03 PM Chapter 5 directory open (fs_opendir() or FSDir_Open()) is initiated on a device that was not present at the last attempted access, C/FS attempts to refresh the device information; if that succeeds, it attempts to refresh the volume information. Files and directories have additional behavior. If a file is opened on a volume, and the underlying device is subsequently removed or changed, all further accesses using the file API (e.g., FSFile_Rd()) will fail with the error code FS_ERR_DEV_CHNGD; all POSIX API functions will return error values. The file should then be closed (to free the file structure). Similarly, if a directory is opened on a volume, and the underlying device is subsequently removed or changed, all further FSDir_Rd() attempts will fail with the error code FS_ERR_DEV_CHNGD; fs_readdir_r() will return 1. The directory should then be closed (to free the directory structure). 5-4 RAW DEVICE IO Opened devices can be accessed directly at the sector level, completely bypassing the file system. Such read and write operations on raw devices are accomplished by using FSDev_Rd() and FSDev_Wr() to respectively read and write one or more sector at a time. However, doing so may have the unwanted side-effect of corrupting an existing file system on the device and as such, should be done carefully. Applications wishing to use both the high level file system API of C/FS and raw device access concurrently may acquire a global lock to a device with FSDev_AccessLock(). While the application has ownership of a device's access lock all higher level operations such as the FSFile_ and FSEntry_ type of functions will wait for the lock to be released. The lock can then be released using FSDev_AccessUnlock() to give back access to the device. When raw device operations are used to make changes on opened files and volumes it is generally required to invalidate them to prevent C/FS from performing inconsistent operations on the file system. A call to FSDev_Invalidate() will make every operations on files and volumes opened on a device fail with an FS_ERR_DEV_CHNGD error. Affected files and volumes will then have to be closed and re-opened to continue, similarly to a removable media change. 72 600-uC-FS-001.book Page 73 Wednesday, October 10, 2012 12:03 PM Partitions 5-5 PARTITIONS A device can be partitioned into two or more regions, and a file system created on one or more of these, each of which could be mounted as a volume. C/FS can handle and make DOS-style partitions, which is a common partitioning system. The first sector on a device with DOS-style partitions is the Master Boot Record (MBR), with a partition table with four entries, each describing a partition. An MBR entry contains the start address of a partition, the number of sectors it contains and its type. The structure of a MBR entry and the MBR sector is shown in Figure 5-4. 4 Flag Start CHS Addr 8 Type End CHS Addr 12 Start LBA Addr 16 Size in Sectors Figure 5-3 Partition entry format (2) Boot Code 448 464 480 496 1st Entry 2nd Entry 3rd Entry 4th Entry Signature (0xAA55) Figure 5-4 Master boot record An application can write an MBR to a device and create an initial partition with FSDev_PartitionInit(). For example, if you wanted to create an initial 256-MB partition on a 1-GB device "ide:0:": FSDev_PartitionInit((CPU_CHAR *)"ide:0:", (FS_SEC_QTY )(512 * 1024), (FS_ERR *)&err); <-- (a) device name <-- (b) size of partition <-- (c) return error 73 600-uC-FS-001.book Page 74 Wednesday, October 10, 2012 12:03 PM Chapter 5 The parameters are the device name (a) and the size of the partition, in sectors (b). If (b) is 0, then the partition will take up the entire device. After this call, the device will be divided as shown in Figure 5-5. This new partition is called a primary partition because its entry is in the MBR. The four circles in the MBR represent the four partition entries; the one that is now used `points to' Primary Partition 1. M B R Primary Partition 1 (256 MB) Unallocated space (768 MB) Figure 5-5 Device after partition initialization More partitions can now be created on the device. Since the MBR has four partition entries, three more can be made without using extended partitions (as discussed below). The function FSDev_PartitionAdd() should be called three times: FSDev_PartitionAdd((CPU_CHAR *)"ide:0:", (FS_SEC_QTY )(512 * 1024), (FS_ERR *)&err); <-- (a) device name <-- (b) size of partition <-- (c) return error Again, the parameters are the device name (a) and the size of the partition, in sectors (b). After this has been done, the device is divided as shown in Figure 5-6. M B R Primary Partition 1 (256 MB) Primary Partition 2 (256 MB) Primary Partition 3 (256 MB) Primary Partition 4 (256 MB) Figure 5-6 Device after four partitions have been created 74 600-uC-FS-001.book Page 75 Wednesday, October 10, 2012 12:03 PM Partitions When first instituted, DOS partitioning was a simple scheme allowing up to four partitions, each with an entry in the MBR. It was later extended for larger devices requiring more with extended partitions, partitions that contains other partitions. The primary extended partition is the extended partition with its entry in the MBR; it should be the last occupied entry. Primary Partition 1 (256 MB) Primary Partitition 3 (128 MB) M B R Primary Partitition 2 (128 MB) An extended partition begins with a partition table that has up to two entries (typically). The first defines a secondary partition which may contain a file system. The second may define another extended partition; in this case, a secondary extended partition, which can contain yet another secondary partition and secondary extended partition. Basically, the primary extended partition heads a linked list of partitions. Primary Extended Partition (512 MB) Secondary Partition (Partition 4) (256 MB) Secondary Extended Partition (256 MB) Secondary Partition (Partition 5) (256 MB) Figure 5-7 Device with five partitions For the moment, extended partitions are not supported in C/FS. 75 600-uC-FS-001.book Page 76 Wednesday, October 10, 2012 12:03 PM Chapter 5 5-6 VOLUME OPERATIONS Five general operations can be performed on a volume: A volume can be opened (mounted). During the opening of a volume, file system control structures are read from the underlying device, parsed and verified. Files can be accessed on a volume. A file is a linear data sequence (`file contents') associated with some logical, typically human-readable identifier (`file name'). Additional properties, such as size, update date/time and access mode (e.g., read-only, write-only, read-write) may be associated with a file. File accesses constitute reading data from files, writing data to files, creating new files, renaming files, copying files, etc. File access is accomplished via file module-level functions, which are covered in Chapter 6, "Files" on page 83. Directories can be accessed on a volume. A directory is a container for files and other directories. Operations include iterating through the contents of the directory, creating new directories, renaming directories, etc. Directory access is accomplished via directory module-level functions, which are covered in Chapter 7, "Directories" on page 93. A volume can be formatted. (More specifically, high-level formatted.) Formatting writes the control information for a file system to the partition on which a volume is located. A volume can be closed (unmounted). During the closing of a volume, any cached data is written to the underlying device and associated structures are freed. For information about using volume names, see section 4-2 "C/FS Device and Volume Names" on page 61. For FAT-specific volume functions, see Chapter 4, "File Systems: FAT" on page 153. 76 600-uC-FS-001.book Page 77 Wednesday, October 10, 2012 12:03 PM Using Volumes Function Description Valid for Unmounted Volume? FSVol_CacheAssign() Assign cache to volume. Yes FSVol_CacheInvalidate() Invalidate cache for volume. No FSVol_CacheFlush() Flush cache for volume. No FSVol_Close() Close (unmount) volume. Yes FSVol_Fmt() Format volume. Yes FSVol_IsMounted() Determine whether volume is mounted. Yes FSVol_LabelGet() Get volume label. No FSVol_LabelSet() Set volume label. No FSVol_Open() Open (mount) volume. ----- FSVol_Query() Get volume information. Yes FSVol_Rd() Read sector on volume. No FSVol_Refresh() Refresh a volume. No FSVol_Wr() Write sector on volume. No Table 5-2 Volume API functions 5-7 USING VOLUMES A volume is opened with FSVol_Open(): FSVol_Open((CPU_CHAR (CPU_CHAR (FS_PARTITION_NBR (FS_ERR *)"ide:0:", *)"ide:0:", *) 0, *)&err); <-<-<-<-- (a) (b) (c) (d) volume name device name partition number return error Listing 5-1 FSVol_Open() The parameters are the volume name (a), the device name (b) and the partition that will be opened (c). There is no restriction on the volume name (a); however, it is typical to give the volume the same name as the underlying device. If the default partition is to be opened, or if the device is not partitioned, then the partition number (c) should be zero. 77 600-uC-FS-001.book Page 78 Wednesday, October 10, 2012 12:03 PM Chapter 5 The return error code from this function provides important information about the volume state: If the return error code is FS_ERR_NONE, then the volume has been mounted and is ready to use. If the return error code is FS_ERR_PARTITION_NOT_FOUND, then no valid file system could be found on the device, or the specified partition does not exist. The device may need to be formatted (see below). If the return error code is FS_ERR_DEV, FS_ERR_DEV_NOT_PRESENT, FS_ERR_DEV_IO or FS_ERR_DEV_TIMEOUT, the device is either not present or did not respond. This is an important consideration for removable devices. The volume is still registered with the file system suite, and the file system will attempt to re-open the volume each time the application accesses it (see section 5-2 "Using Devices" on page 69 for more information). If any other error code is returned, the volume is not registered with the file system. The developer should examine the error code to determine the source of the error. FSVol_Fmt() formats a device, (re-)initializing the file system on the device: FSVol_Fmt((CPU_CHAR *)"ide:0:", (void *) 0, (FS_ERR *)&err); <-- (a) volume name <-- (b) pointer to system configuration <-- (c) return error The parameters are the volume name (a) and a pointer to file system-specific configuration (b). The configuration is not required; if you are willing to accept the default format, a NULL pointer should be passed. Alternatively, the exact properties of the file system can be configured by passing a pointer to a FS_FAT_SYS_CFG structure as the second argument. For more information about the FS_FAT_SYS_CFG structure, see section D-7 "FS_FAT_SYS_CFG" on page 492. 78 600-uC-FS-001.book Page 79 Wednesday, October 10, 2012 12:03 PM Using Volume Cache 5-8 USING VOLUME CACHE File accesses often incur repeated reading of the same volume sectors. On a FAT volume, these may be sectors in the root directory, the area of the file allocation table (FAT) from which clusters are being allocated or data from important (often-read) files. A cache wedged between the system driver and volume layers (as shown in Figure 5-8) will eliminate many unnecessary device accesses. Sector data is stored upon first read or write. Further reads return the cached data; further writes update the cache entry and, possibly, the data on the volume (depending on the cache mode). FAT System Driver fs_sys.* fs_fat*.* Cache Volume fs_vol.* Figure 5-8 Volume cache architecture A cache is defined by three parameters: size, sector type allocation and mode. The size of the cache is the number of sectors that will fit into it at any time. Every sector is classified according to its type, either management, directory or file; the sector type allocation determines the percentage of the cache that will be devoted to each type. The mode determines when cache entries are created (i.e., when sectors are cached) and what happens upon write. 79 600-uC-FS-001.book Page 80 Wednesday, October 10, 2012 12:03 PM Chapter 5 Cache Mode Description Cache Mode #define Read cache Sectors cached upon read; never cached upon write. FS_VOL_CACHE_MODE_RD Sectors cached upon read and write; data FS_VOL_CACHE_MODE_WR_THROUGH Write-through cache on volume always updated upon write. Write-back cache Sectors cached upon read and write; data FS_VOL_CACHE_MODE_WR_BACK on volume never updated upon write. Table 5-3 Cache types 80 600-uC-FS-001.book Page 81 Wednesday, October 10, 2012 12:03 PM Using Volume Cache 5-8-1 CHOOSING CACHE PARAMETERS The following is an example using the cache for the volume "sdcard:0:". The cache is used in write back mode, and the cache parameters are: 25% of cache size is used for management sector, 15% is used for directories sectors and the remaining (60%) is used for file sectors. FSVol_CacheAssign ((CPU_CHAR (FS_VOL_CACHE_API (void (CPU_INT32U (CPU_INT08U (CPU_INT08U (FS_FLAGS (FS_ERR *)"sdcard:0:", *) NULL, *)&CACHE_BUF[0], ) CACHE_BUF_LEN, ) 25, ) 15, ) FS_VOL_CACHE_MODE_WR_BACK, *)&err); <-<-<-<-<-<-<-<-- volume name pointer to vol pointer to the cache buf size see (1) see (2) cache mode used for error cache API cache buf in bytes code if (err != FS_ERR_NONE) { APP_TRACE_INFO ((" Error : could not assign Volume cache")); return; } pfile = FSFile_Open("sdcard:0:\\file.txt", FS_FILE_ACCESS_MODE_WR | FS_FILE_ACCESS_MODE_CACHED, &err); if (pFile == (FS_FILE *)0) { return; } /* DO THE WRITE OPERATIONS TO THE FILE */ FSFile_Close (pFile, &err); FSVol_CacheFlush ("sdcard:0:", &err); <-- Flush volume cache. Listing 5-2 Cache L5-2(1) Percent of cache buffer dedicated to management sectors. L5-2(2) Percent of cache buffer dedicated to directory sectors. 81 600-uC-FS-001.book Page 82 Wednesday, October 10, 2012 12:03 PM Chapter 5 The application using C/FS volume cache should vary the third and fourth parameters passed to FSVol_CacheAssign(), and select the values that give the best performance. For an efficient cache usage, it is better to do not allocate space in the cache for sectors of type file when the write size is greater than sector size. When the cache is used in write back mode, all cache dirty sectors will be updated on the media storage only when the cache is flushed. 5-8-2 OTHER CACHING AND BUFFERING MECHANISMS Volume cache is just one of several important caching mechanisms, which should be balanced for optimal performance within the bounds of platform resources. The second important software mechanism is the file buffer (see section 6-1-3 "Configuring a File Buffer" on page 87), which makes file accesses more efficient by buffering data so a full sector's worth will be read or written. Individual devices or drivers may also integrate a cache. Standard hard drives overcome long seek times by buffering extra data upon read (in anticipation of future requests) or clumping writes to eliminate unnecessary movement. The latter action can be particularly powerful, but since it may involve re-ordering the sequence of sector writes will eliminate any guarantee of fail-safety of most file systems. For that reason, write cache in most storage devices should be disabled. A driver may implement a buffer to reduce apparent write latency. Before a write can occur to a flash medium, the driver must find a free (erased) area of a block; occasionally, a block will need to be erased to make room for the next write. Incoming data can be buffered while the long erase occurs in the background, thereby uncoupling the application's wait time from the real maximum flash write time. The ideal system might use both volume cache and file buffers. A volume cache is most powerful when confined to the sector types most subject to repeated reads: management and directory. Caching of files, if enabled, should be limited to important (often-read) files. File buffers are more flexible, since they cater to the many applications that find small reads and writes more convenient than those of full sectors. 82 600-uC-FS-001.book Page 83 Wednesday, October 10, 2012 12:03 PM Chapter 6 Files An application stores information in a file system by creating a file or appending new information to an existing file. At a later time, this information may be retrieved by reading the file. Other functions support these capabilities; for example, the application can move to a specified location in the file or query the file system to get information about the file. These functions, which operate on file structures (FS_FILEs), are grouped under file access (or simply file) functions. The available file functions are listed in Table 6-1. A separate set of file operations (or entry) functions manage the files and directories available on the system. Using these functions, the application can copy, create, delete and rename files, and get and set a file or directory's attributes and date/time. The available entry functions are listed in Table 6-3. The entry functions and the FSFile_Open() function accept full file paths. For information about using file and path names, see section 4-3 "C/FS File and Directory Names and Paths" on page 62. The functions listed in Table 6-1 and Table 6-3 are core functions in the file access module (FSFile_####() functions) and entry module (FSEntry_####() functions). These are matched, in most cases, by API level functions that correspond to standard C or POSIX functions. The core and API functions provide basically the same functionality; the benefits of the former are enhanced capabilities, a consistent interface and meaningful return error codes. 83 600-uC-FS-001.book Page 84 Wednesday, October 10, 2012 12:03 PM Chapter 6 6-1 FILE ACCESS FUNCTIONS The file access functions provide an API for performing a sequence of operations on a file located on a volume's file system. The file object pointer returned when a file is opened is passed as the first argument of all file access functions (a characteristic which distinguishes these from the entry access functions), and the file object so referenced maintains information about the actual file (on the volume) and the state of the file access. The file access state includes the file position (the next place data will be read/written), error conditions and (if file buffering is enabled) the state of any file buffer. Function Description FSFile_BufAssign() Assign buffer to a file. FSFile_BufFlush() Write buffered data to volume. FSFile_Close() Close a file. FSFile_ClrErr() Clear error(s) on a file. FSFile_IsEOF() Determine whether a file is at EOF. FSFile_IsErr() Determine whether error occurred on a file. FSFile_IsOpen() Determine whether a file is open or not. FSFile_LockGet() Acquire task ownership of a file. FSFile_LockSet() Release task ownership of a file. FSFile_LockAccept() Acquire task ownership of a file (if available). FSFile_Open() Open a file. FSFile_PosGet() Get file position. FSFile_PosSet() Set file position. FSFile_Query() Get information about a file. FSFile_Rd() Read from a file. FSFile_Truncate() Truncate a file. FSFile_Wr() Write to a file. Table 6-1 File access functions 84 600-uC-FS-001.book Page 85 Wednesday, October 10, 2012 12:03 PM File Access Functions 6-1-1 OPENING FILES When an application needs to access a file, it must first open it using fs_fopen() or FSFile_Open(). For most applications, the former with its familiar interface suffices. In some cases, the flexibility of the latter is demanded: file ptr --> p_file = FSFile_Open ("\\file.txt", <-- file name FS_FILE_ACCESS_MODE_RD, <-- access mode &err); <-- return error if (p_file == (FS_FILE *)0) { /* $$$$ Handle error */ } The return value of this function should always be verified as non-NULL before the application proceeds to access the file. The second argument to this function is a logical OR of mode flags: FS_FILE_ACCESS_MODE_RD File opened for reads. FS_FILE_ACCESS_MODE_WR File opened for writes. FS_FILE_ACCESS_MODE_CREATE File will be created, if necessary. FS_FILE_ACCESS_MODE_TRUNC File length will be truncated to 0. FS_FILE_ACCESS_MODE_APPEND All writes will be performed at EOF. FS_FILE_ACCESS_MODE_EXCL File will be opened if and only if it does not already exist. FS_FILE_ACCESS_MODE_CACHED File data will be cached. For example, if you wanted to create a file to write to if and only if it does not exist, you would use the flags FS_FILE_ACCESS_MODE_WR | FS_FILE_ACCESS_MODE_CREATE | FS_FILE_ACCESS_MODE_EXCL It is impossible to do this in a single, atomic operation using fs_fopen(). 85 600-uC-FS-001.book Page 86 Wednesday, October 10, 2012 12:03 PM Chapter 6 The table below lists the mode flag equivalents of the fs_fopen() mode strings. "r" or "rb" FS_FILE_ACCESS_MODE_RD "w" or "wb" FS_FILE_ACCESS_MODE_WR FS_FILE_ACCESS_MODE_CREATE FS_FILE_ACCESS_MODE_TRUNC "a" or "ab" FS_FILE_ACCESS_MODE_WR FS_FILE_ACCESS_MODE_CREATE FS_FILE_ACCESS_MODE_APPEND "r+" or "rb+" or "r+b" FS_FILE_ACCESS_MODE_RD FS_FILE_ACCESS_MODE_WR "w+" or "wb+" or "w+b" FS_FILE_ACCESS_MODE_RD FS_FILE_ACCESS_MODE_WR FS_FILE_ACCESS_MODE_CREATE FS_FILE_ACCESS_MODE_TRUNC "a+" or "ab+" or "a+b" FS_FILE_ACCESS_MODE_RD FS_FILE_ACCESS_MODE_WR FS_FILE_ACCESS_MODE_CREATE FS_FILE_ACCESS_MODE_APPEND Table 6-2 fopen() mode strings and mode equivalents 6-1-2 GETTING INFORMATION ABOUT A FILE Detailed information about an open file, such as size and date/time stamps, can be obtained using the FSFile_Query() function: FS_ENTRY_INFO info; FSFile_Query(p_file, <-- file pointer &info, <-- pointer to info structure &err); <-- return error The FS_ENTRY_INFO structure has the following members: Attrib contains the file attributes (see section 6-2-1 "File and Directory Attributes" on page 90). Size is the size of the file, in octets. 86 600-uC-FS-001.book Page 87 Wednesday, October 10, 2012 12:03 PM File Access Functions DateTimeCreate is the creation timestamp of the file. DateAccess is the access timestamp (date only) of the file. DateTimeWr is the last write (or modification) timestamp of the file. BlkCnt is the number of blocks allocated to the file. For a FAT file system, this is the number of clusters occupied by the file data. BlkSize is the size of each block allocated in octets. For a FAT file system, this is the size of a cluster. DateTimeCreate, DateAccess and DateTimeWr are structures of type CLK_TS_SEC. 6-1-3 CONFIGURING A FILE BUFFER The file module has functions to assign and flush a file buffer that are equivalents to POSIX API functions; the primary difference is the advantage of valuable return error codes to the application. File Module Function POSIX API Equivalent void FSFile_BufAssign (FS_FILE *p_file, void *p_buf, FS_FLAGS mode, CPU_SIZE_T size, FS_ERR *p_err); int fs_setvbuf (FS_FILE *stream, char *buf, int mode, fs_size_t size); void FSFile_BufFlush (FS_FILE FS_ERR int fs_fflush (FS_FILE *p_file, *p_err); *stream); For more information about and an example of configuring a file buffer, see section 8-3-3 "Configuring a File Buffer" on page 104. 87 600-uC-FS-001.book Page 88 Wednesday, October 10, 2012 12:03 PM Chapter 6 6-1-4 FILE ERROR FUNCTIONS The file module has functions get and clear a file's error status that are almost exact equivalents to POSIX API functions; the primary difference is the advantage of valuable return error codes to the application. File Module Function void FSFile_ClrErr CPU_BOOLEAN CPU_BOOLEAN POSIX API Equivalent (FS_FILE FS_ERR FSFile_IsErr (FS_FILE FS_ERR FSFile_IsEOF (FS_FILE FS_ERR *p_file, *p_err); *p_file, *p_err); *p_file, *p_err); void fs_clearerr (FS_FILE *stream); int fs_ferror (FS_FILE *stream); int fs_feof (FS_FILE *stream); For more information about this functionality, see section 8-3-4 "Diagnosing a File Error" on page 106. 6-1-5 ATOMIC FILE OPERATIONS USING FILE LOCK The file module has functions lock files across several operations that are almost exact equivalents to POSIX API functions; the primary difference is the advantage of valuable return error codes to the application. File Module Function void FSFile_LockGet (FS_FILE FS_ERR void FSFile_LockAccept (FS_FILE FS_ERR void FSFile_LockSet (FS_FILE FS_ERR POSIX API Equivalent *p_file, *p_err); *p_file, *p_err); *p_file, *p_err); void fs_flockfile (FS_FILE *file); int fs_ftrylockfile (FS_FILE *file); void fs_funlockfile (FS_FILE *file); For more information about and an example of using file locking, see section 8-3-5 "Atomic File Operations Using File Lock" on page 106. 88 600-uC-FS-001.book Page 89 Wednesday, October 10, 2012 12:03 PM Entry Access Functions 6-2 ENTRY ACCESS FUNCTIONS The entry access functions provide an API for performing single operations on file system entries (files and directories), such as copying, renaming or deleting. Each of these operations is atomic; consequently, in the absence of device access errors, either the operation will have completed or no change to the storage device will have been made upon function return. One of these functions, FSEntry_Query(), obtains information about an entry (including the attributes, date/time stamp and file size). Two functions set entry properties, FSEntry_AttribSet() and FSEntry_TimeSet(), which set a file's attributes and date/time stamp. A new file entry can be created with FSEntry_Create() or an existing entry deleted, copied or renamed (with FSEntry_Del(), FSEntry_Copy() or FSEntry_Rename()). Function Description FSEntry_AttribSet() Set a file or directory's attributes. FSEntry_Copy() Copy a file. FSEntry_Create() Create a file or directory. FSEntry_Del() Delete a file or directory. FSEntry_Query() Get information about a file or directory. FSEntry_Rename() Rename a file or directory. FSEntry_TimeSet() Set a file or directory's date/time. Table 6-3 Entry API functions 89 600-uC-FS-001.book Page 90 Wednesday, October 10, 2012 12:03 PM Chapter 6 6-2-1 FILE AND DIRECTORY ATTRIBUTES The FSEntry_Query() function gets information about file system entry, including its attributes, which indicate whether it is a file or directory, writable or read-only, and visible or hidden: FS_FLAGS attrib; FS_ENTRY_INFO info; FSEntry_Query("path_name", &info, &err); attrib = info.Attrib; <-- pointer to full path name <-- pointer to info <-- return error The return value is a logical OR of attribute flags: FS_ENTRY_ATTRIB_RD Entry is readable. FS_ENTRY_ATTRIB_WR Entry is writable. FS_ENTRY_ATTRIB_HIDDEN Entry is hidden from user-level processes. FS_ENTRY_ATTRIB_DIR Entry is a directory. FS_ENTRY_ATTRIB_ROOT_DIR Entry is a root directory. If no error is returned and FS_ENTRY_ATTRIB_DIR is not set, then the entry is a file. An entry can be made read-only (or writable) or hidden (or visible) by setting its attributes: 90 600-uC-FS-001.book Page 91 Wednesday, October 10, 2012 12:03 PM Entry Access Functions The second argument should be the logical OR of relevant attribute flags. attrib = FS_ENTRY_ATTRIB_RD; FSEntry_AttribSet("path_name", <-- pointer to full path name attrib, <-- attributes &err); <-- return error FS_ENTRY_ATTRIB_RD Entry is readable. FS_ENTRY_ATTRIB_WR Entry is writable. FS_ENTRY_ATTRIB_HIDDEN Entry is hidden from user-level processes. If a flag is clear (not OR'd in), then that attribute will be clear. In the example above, the entry will be made read-only (i.e., not writable) and will be visible (i.e., not hidden) since the WR and HIDDEN flags are not set in attrib. Since there is no way to make files write-only (i.e., not readable), the RD flag should always be set. 6-2-2 CREATING NEW FILES AND DIRECTORIES A new file can be created using FSFile_Open() or fs_fopen(), if opened in write or append mode. There are a few other ways that new files can be created (most of which also apply to new directories). The simplest is the FSEntry_Create() function, which just makes a new file or directory: FSEntry_Create("\\file.txt", FS_ENTRY_TYPE_FILE, DEF_NO, &err); <-<-<-<-- file name means entry will be a file DEF_NO means creation NOT exclusive return error If the second argument, entry_type, is FS_ENTRY_TYPE_DIR the new entry will be a directory. The third argument, excl, indicates whether the creation should be exclusive. If it is exclusive (excl is DEF_YES), nothing will happen if the file already exists. Otherwise, the file currently specified by the file name will be deleted and a new empty file with that name created. 91 600-uC-FS-001.book Page 92 Wednesday, October 10, 2012 12:03 PM Chapter 6 Similar functions exist to copy and rename an entry: FSEntry_Copy("\\dir\\src.txt", <-- source file name "\\dir\\dest.txt , DEF_NO, &err); FSEntry_Rename ("\\dir\\oldname.txt", "\\dir\\newname.txt", DEF_NO, &err); <-<-<-<-<-<-<-- destination file name DEF_NO means creation not exclusive return error old file name new file name DEF_NO means creation not exclusive return error FSEntry_Copy() can only be used to copy files. The first two arguments of each of these are both full paths; the second path is not relative to the parent directory of the first. As with FSEntry_Create(), the third argument of each, excl, indicates whether the creation should be exclusive. If it is exclusive (excl is DEF_YES), nothing will happen if the destination or new file already exists. 6-2-3 DELETING FILES AND DIRECTORIES A file or directory can be deleted using FSEntry_Del(): FSEntry_Del("\\dir", FS_ENTRY_TYPE_DIR, &err); <-- entry name <-- means entry must be a dir <-- return error The second argument, entry_type, restricts deletion to specific types. If it is FS_ENTRY_TYPE_DIR, then the entry specified by the first argument must be a directory; if it is a file, an error will be returned. If it is FS_ENTRY_TYPE_FILE, then the entry must be a file. If it is FS_ENTRY_TYPE_ANY, then the entry will be deleted whether it is a file or a directory. 92 600-uC-FS-001.book Page 93 Wednesday, October 10, 2012 12:03 PM Chapter 7 Directories An application stores information in a file system by creating a file or appending new information to an existing file. At a later time, this information may be retrieved by reading the file. However, if a certain file must be found, or all files may be listed, the application can iterate through the entries in a directory using the directory access (or simply directory) functions. The available directory functions are listed in Table 6-1. A separate set of directory operations (or entry) functions manage the files and directories available on the system. Using these functions, the application can create, delete and rename directories, and get and set a directory's attributes and date/time. More information about the entry functions can be found in section 6-2 "Entry Access Functions" on page 89. The entry functions and the directory Open() function accept one or more full directory paths. For information about using file and path names, see section 4-3 "C/FS File and Directory Names and Paths" on page 62. The functions listed in Table 7-1 are core functions in the directory access module (FSDir_####() functions). These are matched by API level functions that correspond to standard C or POSIX functions. More information about the API-level functions can be found in Chapter 8, "POSIX API" on page 95. The core and API functions provide basically the same functionality; the benefits of the former are enhanced capabilities, a consistent interface and meaningful return error codes. 93 600-uC-FS-001.book Page 94 Wednesday, October 10, 2012 12:03 PM Chapter 7 7-1 DIRECTORY ACCESS FUNCTIONS The directory access functions provide an API for iterating through the entries within a directory. The FSDir_Open() function initiates this procedure, and each subsequent call to FSDir_Rd() (until all entries have been examined) returns a FS_DIRENT which holds information about a particular entry. The FSDir_Close() function releases any file system structures and locks. Function Description FSDir_Open() Open a directory. FSDir_Close() Close a directory FSDir_Rd() Read a directory entry. FSDir_IsOpen() Determine whether a directory is open or not. Table 7-1 Directory API functions These functions are almost exact equivalents to POSIX API functions; the primary difference is the advantage of valuable return error codes to the application. POSIX API Equivalent Directory Module Function FS_DIR *FSDir_Open (CPU_CHAR FS_ERR *p_name_full, *p_err); void FSDir_Close(FS_DIR FS_ERR *p_dir, *p_err); void FSDir_Rd FS_DIR *fs_opendir (const char int (FS_DIR *p_dir, FS_DIR_ENTRY *p_dir_entry, FS_ERR *p_err); int fs_closedir (FS_DIR *dirname); *dirp); fs_readdir_r (FS_DIR *dirp, struct fs_dirent *entry, struct fs_dirent **result); For more information about and an example of using directories, see section 8-4 "Directory Access Functions" on page 107. 94 600-uC-FS-001.book Page 95 Wednesday, October 10, 2012 12:03 PM Chapter 8 POSIX API Important warning about the POSIX API The C/FS implementation of the POSIX API is not 100% compliant. Most notably, the errno error flag isn't set when an error occurs and thus it is recommended to use the C/FS proprietary API (FSFile_####(), FSDir_####(), FSEntry_####(), etc.). The best-known API for accessing and managing files and directories is specified within the POSIX standard (IEEE Std 1003.1). The basis of some of this functionality, in particular buffered input/output, lies in the ISO C standard (ISO/IEC 9899), though many extensions provide new features and clarify existing behaviors. Functions and macros prototyped in four header files are of particular importance: stdio.h. Standard buffered input/output (fopen(), fread(), etc), operating on FILE objects. dirent.h. Directory accesses (opendir(), readdir(), etc), operating on DIR objects. unistd.h. Miscellaneous functions, including working (chdir(), getcwd()), ftruncate() and rmdir(). sys/stat.h. File statistics functions and mkdir(). directory management C/FS provides a POSIX-compatible API based on a subset of the functions in these four header files. To avoid conflicts with the user compilation environment, files, functions and objects are renamed: All functions begin with `fs_'. For example, fopen() is renamed fs_fopen(), opendir() is renamed fs_opendir(), getcwd() is renamed fs_getcwd(), etc. 95 600-uC-FS-001.book Page 96 Wednesday, October 10, 2012 12:03 PM Chapter 8 All objects begin with `FS_'. So fs_fopen() returns a pointer to a FS_FILE and fs_opendir() returns a pointer to a FS_DIR. Some argument types are renamed. For example, the second and third parameters of fs_fread() are typed fs_size_t to avoid conflicting with other size_t definitions. 8-1 SUPPORTED FUNCTIONS The supported POSIX functions are listed in the table below. These are divided into four groups. First, the functions which operate on file objects (FS_FILEs) are grouped under file access (or simply file) functions. An application stores information in a file system by creating a file or appending new information to an existing file. At a later time, this information may be retrieved by reading the file. Other functions support these capabilities; for example, the application can move to a specified location in the file or query the file system to get information about the file. A separate set of file operations (or entry) functions manage the files and directories available on the system. Using these functions, the application can create, delete and rename files and directories. The entries within a directory can be traversed using the directory access (or simply directory) functions, which operate on directory objects (FS_DIRs). The name and properties of the entries are returned within a struct fs_dirent structure. The final group of functions is the working directory functions. For information about using file and path names, see section 4-3 "C/FS File and Directory Names and Paths" on page 62. Function POSIX Equivalent Function POSIX Equivalent fs_asctime_r() asctime_r() fs_ftruncate() ftruncate() fs_chdir() chdir() fs_ftrylockfile() ftrylockfile() fs_clearerr() clearerr() fs_funlockfile() funlockfile() fs_closedir() closedir() fs_fwrite() fwrite() fs_ctime_r() ctime_r() fs_getcwd() getcwd() fs_fclose() fclose() fs_localtime_r() localtime_r() fs_feof() feof() fs_mkdir() mkdir() 96 600-uC-FS-001.book Page 97 Wednesday, October 10, 2012 12:03 PM Working Directory Functions Function POSIX Equivalent Function POSIX Equivalent fs_ferror() ferror() fs_mktime() mktime() fs_fflush() fflush() fs_rewind() rewind() fs_fgetpos() fgetpos() fs_opendir() opendir() fs_flockfile() flockfile() fs_readdir_r() readdir_r() fs_fopen() fopen() fs_remove() remove() fs_fread() fread() fs_rename() rename() fs_fseek() fseek() fs_rmdir() rmdir() fs_fsetpos() fsetpos() fs_setbuf() setbuf() fs_fstat() fstat() fs_setvbuf() setvbuf() fs_ftell() ftell() fs_stat() stat() Table 8-1 POSIX API functions 8-2 WORKING DIRECTORY FUNCTIONS Normally, all file or directory paths must be absolute, either on the default volume or on an explicitly-specified volume: p_file1 = fs_fopen("\\file.txt", "r"); p_file2 = fs_fopen("sdcard:0:\\file.txt", "r"); /* File on default volume */ /* File on explicitly-specified volume */ If working directory functionality is enabled, paths may be specified relative to the working directory of the current task: p_file2 = fs_fopen("file.txt", "r"); p_file1 = fs_fopen("..\\file.txt", "r"); /* File in working directory */ /* File in parent of working directory */ The two standard special path components are supported. The path component ".." moves to the parent of the current working directory. The path component "." makes no change; essentially, it means the current working directory. 97 600-uC-FS-001.book Page 98 Wednesday, October 10, 2012 12:03 PM Chapter 8 fs_chdir() is used to set the working directory. If a relative path is employed before any working directory is set, the root directory of the default volume is used. The application can get the working directory with fs_getcwd(). A terminal interface may use this function to implement an equivalent to the standard pwd (print working directory) command, while calling fs_chdir() to carry out a cd operation. If working directories are enabled, the C/Shell commands for C/FS manipulate and access the working directory with fs_chdir() and fs_getcwd() (see also Appendix F, "Shell Commands" on page 509). 8-3 FILE ACCESS FUNCTIONS The file access functions provide an API for performing a sequence of operations on a file located on a volume's file system. The file object pointer returned when a file is opened is passed as an argument of all file access function, and the file object so referenced maintains information about the actual file (on the volume) and the state of the file access. The file access state includes the file position (the next place data will be read/written), error conditions and (if file buffering is enabled) the state of any file buffer. As data is read from or written to a file, the file position is incremented by the number of bytes transferred from/to the volume. The file position may also be directly manipulated by the application using the position set function (fs_fsetpos()), and the current absolute file position may be gotten with the position get function (fs_fgetpos()), to be later used with the position set function. 98 600-uC-FS-001.book Page 99 Wednesday, October 10, 2012 12:03 PM File Access Functions e os Cl Cl os ed Closed d Must be Closed r ro Er V ch olum an e ge Closed Error Clear error Open W ion sit po h e l s t fi flu Se or Se t os itio (fil e rite file p R no ead ta tE OF ) Ready n Read Write Reading Write (file at EOF) Writing Figure 8-1 File state transitions The file maintains flags that reflect errors encountered in the previous file access, and subsequent accesses will fail (under certain conditions outlined here) unless these flags are explicitly cleared (using fs_clearerr()). There are actually two sets of flags. One reflects whether the file encountered the end-of-file (EOF) during the previous access, and if this is set, writes will not fail, but reads will fail. The other reflects device errors, and no subsequent file access will succeed (except file close) unless this is first cleared. The functions fs_ferror() and fs_feof() can be used to get the state of device error and EOF conditions, respectively. If file buffering is enabled (FS_CFG_FILE_BUF_EN is DEF_ENABLED), then input/output buffering capabilities can be used to increase the efficiency of file reads and writes. A buffer can be assigned to a file using fs_setbuf() or fs_setvbuf(); the contents of the buffer can be flushed to the storage device using fs_fflush(). 99 600-uC-FS-001.book Page 100 Wednesday, October 10, 2012 12:03 PM Chapter 8 If a file is shared between several tasks in an application, a file lock can be employed to guarantee that a series of file operations are executed atomically. fs_flockfile() (or its non-blocking equivalent fs_ftrylockfile()) acquires the lock for a task (if it does not already own it). Accesses from other tasks will be blocked until a fs_funlockfile() is called. This functionality is available if FS_CFG_FILE_LOCK_EN is DEF_ENABLED. 8-3-1 OPENING, READING AND WRITING FILES When an application needs to access a file, it must first open it using fs_fopen(): file pointer --> p_file = fs_fopen("\\file.txt", <-- file name "w+"); <-- mode string if (p_file == (FS_FILE *)0) { /* $$$$ Handle error */ } The return value of this function should always be verified as non-NULL before the application proceeds to access the file. The first argument of this function is the path of the file; if working directories are disabled, this must be the absolute file path, beginning with either a volume name or a `\' (see section 4-3 "C/FS File and Directory Names and Paths" on page 62). The second argument of this function is a string indicating the mode of the file; this must be one of the strings shown in the table below. Note that in all instances, the `b' (binary) option has no affect on the behavior of file accesses. fs_fopen() Mode String Read? Write? Truncate? Create? Append? "r" or "rb" Yes No No No No "w" or "wb" No Yes Yes Yes No "a" or "ab" No Yes No Yes Yes "r+" or "rb+" or "r+b" Yes Yes No No No "w+" or "wb+" or "w+b" Yes Yes Yes Yes No "a+" or "ab+" or "a+b" Yes Yes No Yes Yes Table 8-2 fs_fopen() mode strings interpretations 100 600-uC-FS-001.book Page 101 Wednesday, October 10, 2012 12:03 PM File Access Functions After a file is opened, any of the file access functions valid for that its mode can be called. The most commonly used functions are fs_fread() and fs_fwrite(), which read or write a certain number of `items' from a file: number of items read --> cnt = fs_fread(p_buf, 1, <-- pointer to buffer <-- size of each item 100, <-- number of items p_file); <-- pointer to file The return value, the number of items read (or written), should be less than or equal to the third argument. If the operation is a read, this value may be less than the third argument for one of two reasons. First, the file could have encountered the end-of-file (EOF), which means that there is no more data in the file. Second, the device could have been removed, or some other error could have prevented the operation. To diagnose the cause, the fs_feof() function should be used. This function returns a non-zero value if the file has encountered the EOF. Once the file access is complete, the file must be closed; if an application fails to close files, then the file system suite resources such as file objects may be depleted. An example of reading a file is given in Listing 8-1. 101 600-uC-FS-001.book Page 102 Wednesday, October 10, 2012 12:03 PM Chapter 8 void App_Fnct (void) { FS_FILE *p_file; fs_size_t unsigned char . cnt; buf[50]; . . p_file = fs_fopen("\\file.txt", "r"); /* Open file. */ if (p_file != (FS_FILE *)0) { /* If file is opened ... /* ... read from file. */ */ do { cnt = fs_fread(&buf[0], 1, sizeof(buf), p_file); if (cnt > 0) { APP_TRACE_INFO(("Read %d bytes.\r\n", cnt)); } } while (cnt >= sizeof(buf)); eof = fs_feof(p_file); /* if (eof != 0) { /* APP_TRACE_INFO(("Reached EOF.\r\n")); } else { err = fs_ferror(p_file); /* if (err != 0) { /* APP_TRACE_INFO(("Read error.\r\n")); } } fs_fclose(p_file); /* } else { Chk for EOF. See Note #1. */ */ Chk for error. See Note #2. */ */ Close file. */ APP_TRACE_INFO(("Could not open \"\\file.txt\".\r\n")); } . . . } Listing 8-1 Example file read L8-1(1) To determine whether a file read terminates because of reaching the EOF or a device error/removal, the EOF condition should be checked using fs_feof(). L8-1(2) In most situations, either the EOF or the error indicator will be set on the file if the return value of fs_fread() is smaller than the buffer size. Consequently, this check is unnecessary. 102 600-uC-FS-001.book Page 103 Wednesday, October 10, 2012 12:03 PM File Access Functions 8-3-2 GETTING OR SETTING THE FILE POSITION Another common operation is getting or setting the file position. The fs_fgetpos() and fs_fsetpos() allow the application to `store' a file location, continue reading or writing the file, and then go back to that place at a later time. An example of using file position get and set is given in Listing 8-2. void App_Fnct (void) { FS_FILE *p_file; fs_fpos_t pos; int err; . . . p_file = fs_fopen("\file.txt", "r"); /* Open file ... if (p_file == (FS_FILE *)0) { APP_TRACE_INFO(("Could not open file.")); return; } . . /* ... read from file. . err = fs_fgetpos(p_file, &pos); /* Save file position ... if (err != 0) { APP_TRACE_INFO(("Could not get file position.")); return; } . . /* ... read some more from file. . err = fs_fsetpos(p_file, &pos); /* Set file to saved position ... if (err != 0) { APP_TRACE_INFO(("Could not set file position.")); return; } . . /* ... read some more from file. . FS_fclose(p_file); /* When finished, close file. . . . } */ */ */ */ */ */ */ Listing 8-2 Example file position set/get 103 600-uC-FS-001.book Page 104 Wednesday, October 10, 2012 12:03 PM Chapter 8 8-3-3 CONFIGURING A FILE BUFFER In order to increase the efficiency of file reads and writes, input/output buffering capabilities are provided. Without an assigned buffer, reads and writes will be immediately performed within fs_fread() and fs_fwrite(). Once a buffer has been assigned, data will always be read from or written to the buffer; device access will only occur once the file position moves beyond the window represented by the buffer. fs_setbuf() and fs_setvbuf() assign the buffer to a file. The contents of the buffer can be flushed to the storage device with fs_fflush(). If a buffer is assigned to a file that was opened in update (read/write) mode, then a write may only be followed by a read if the buffer has been flushed (by calling fs_fflush() or a file positioning function). A read may be followed by a write only if the buffer has been flushed, except when the read encountered the end-of-file, in which case a write may happen immediately. The buffer is automatically flushed when the file is closed. File buffering is particularly important when data is written in small chunks to a medium with slow write time or limited endurance. An example is NOR flash, or even NAND flash, where write times are much slower than read times, and the lifetime of device is constrained by limits on the number of times each block can be erased and programmed. 104 600-uC-FS-001.book Page 105 Wednesday, October 10, 2012 12:03 PM File Access Functions static void CPU_INT32U App_FileBuf[512 / 4]; /* Define file buffer. */ App_Fnct (void) { CPU_INT08U . data1[50]; . . p_file = FS_fopen("\\file.txt", "w"); if (p_file != (FS_FILE *)0) { /* Set buffer (see Note #1). fs_setvbuf(p_file, (void *)App_FileBuf, FS__IOFBF, sizeof(App_FileBuf)); . . */ . fs_fflush(p_file); /* Make sure data is written to file. */ . . . fs_fclose(p_file); /* When finished, close file. */ } . . . } Listing 8-3 Example file buffer usage L8-3(1) The buffer must be assigned immediately after opening the file. An attempt to set the buffer after read or writing the file will fail. L8-3(2) While it is not necessary to flush the buffer before closing the file, some applications may want to make sure at certain points that all previously written data is stored on the device before writing more. 105 600-uC-FS-001.book Page 106 Wednesday, October 10, 2012 12:03 PM Chapter 8 8-3-4 DIAGNOSING A FILE ERROR The file maintains flags that reflect errors encountered in the previous file access, and subsequent accesses will fail (under certain conditions outlined here) unless these flags are explicitly cleared (using fs_clearerr()). There are actually two sets of flags. One reflects whether the file encountered the end-of-file (EOF) during the previous access, and if this is set, writes will not fail, but reads will fail. The other reflects device errors, and no subsequent file access will succeed (except file close) unless this is first cleared. The functions fs_ferror() and fs_feof() can be used to get the state of device error and EOF conditions, respectively. 8-3-5 ATOMIC FILE OPERATIONS USING FILE LOCK If a file is shared between several tasks in an application, the file lock can be employed to guarantee that a series of file operations are executed atomically. fs_flockfile() (or its non-blocking equivalent fs_ftrylockfile()) acquires the lock for a task (if it does not already own it). Accesses from other tasks will be blocked until fs_funlockfile() is called. Each file actually has a lock count associated with it. This allows nested calls by a task to acquire a file lock; each of those calls must be matched with a call to fs_funlockfile(). void App_Fnct (void) { unsigned char data1[50]; unsigned char data2[10]; . . . if (App_FilePtr != (FS_FILE *)0) { fs_flockfile(App_FilePtr); /* Lock file. /* See Note #1. /* Wr data atomically. fs_fwrite(data1, 1, sizeof(data1), App_FilePtr); fs_fwrite(data2, 1, sizeof(data1), App_FilePtr); fs_funlockfile(App_FilePtr); /* Unlock file. */ */ */ */ } . . . } Listing 8-4 Example file lock usage 106 600-uC-FS-001.book Page 107 Wednesday, October 10, 2012 12:03 PM Directory Access Functions L8-4(1) fs_flockfile() will block the calling task until the file is available. If the task must write to the file only if no other task is currently accessing it, the non-blocking function fs_funlockfile() can be used. 8-4 DIRECTORY ACCESS FUNCTIONS The directory access functions provide an API for iterating through the entries within a directory. The fs_opendir() function initiates this procedure, and each subsequent call to fs_readdir_r() (until all entries have been examined) returns information about a particular entry in a struct fs_dirent. The fs_closedir() function releases any file system structures and locks. Figure 8-2 gives an example using the directory access functions to list the files in a directory. An example result of listing a directory is shown in Figure 4-1. void App_Fnct (void) { FS_DIR *p_dir; struct fs_dirent dirent; struct fs_dirent *p_dirent; char str[50]; char *p_cwd_path; fs_time_t ts; . . . p_dir = fs_opendir(p_cwd_path); /* Open dir. if (p_dir != (FS_DIR *)0) { (void)fs_readdir_r(pdir, &dirent, &p_dirent); /* Rd first dir entry. if (p_dirent == (FS_DIRENT *)0) { /* If NULL ... dir is empty. APP_TRACE_INFO(("Empty dir: %s.\r\n", p_cwd_path)); } else { /* Fmt info for each entry. Str_Copy(str, "-r--r--r-: "); while (p_dirent != (struct dirent *)0) { /* Chk if file is dir. if (DEF_BIT_IS_SET(dirent.Info.Attrib, FS_ENTRY_ATTRIB_DIR) == DEF_YES) { str[0] = `d'; } /* Chk if file is rd only. */ */ */ */ */ */ 107 600-uC-FS-001.book Page 108 Wednesday, October 10, 2012 12:03 PM Chapter 8 if (DEF_BIT_IS_SET(dirent.Info.Attrib, FS_ENTRY_ATTRIB_WR) == DEF_YES) { str[2] = `w'; str[5] = `w'; str[8] = `w'; } /* Get file size. */ if (p_dirent->Info.Size == 0) { if (DEF_BIT_IS_CLR(dirent.Info.Attrib, FS_ENTRY_ATTRIB_DIR) == DEF_YES) { Str_Copy(&str[11]," 0"); } } else { Str_FmtNbr_Int32U(dirent.Info.Size, 10, 10, `0', DEF_NO, DEF_NO, &str[11]); } /* Get file date/time. */ if (p_dirent->Info.DateTimeCreate.Month != 0) { Str_Copy(&str[22], (CPU_CHAR *)App_MonthNames[dirent.Info.DateTimeCreate.Month - 1]); Str_FmtNbr_Int32U(dirent.Info.DateTimeWr.Day, 2, 10, ` `, DEF_NO, DEF_NO, &str[26]); Str_FmtNbr_Int32U(dirent.Info.DateTimeWr.Hour, 2, 10, ` ', DEF_NO, DEF_NO, &str[29]); Str_FmtNbr_Int32U(dirent.Info.DateTimeWr.Minute, 2, 10, ` ', DEF_NO, DEF_NO, &str[32]); } /* Output info for entry. APP_TRACE_INFO(("%s%s\r\n", str, dirent.Name)); /* Rd next dir entry. (void)fs_readdir_r(pdir, &dirent, &p_dirent); */ */ } } fs_closedir(p_dir); /* Close dir. */ /* If dir could not be opened ... */ } else { /* ... dir does not exist. */ APP_TRACE_INFO(("Dir does not exist: %s.\r\n", p_cwd_path)); } . . . } Listing 8-5 Directory listing output (example) 108 600-uC-FS-001.book Page 109 Wednesday, October 10, 2012 12:03 PM Entry Access Functions Figure 8-2 Example directory listing The second argument fs_readdir_r(), is a pointer to a struct fs_dirent, which has two members. The first is Name, which holds the name of the entry; the second is Info, which has file information. For more information about the struct fs_dirent structure, see section D-5 "FS_DIR_ENTRY (struct fs_dirent)" on page 489. 8-5 ENTRY ACCESS FUNCTIONS The entry access functions provide an API for performing single operations on file system entries (files and directories), such as renaming or deleting a file. Each of these operations is atomic; consequently, in the absence of device access errors, either the operation will have completed or no change to the storage device will have been made upon function return. A new directory can be created with fs_mkdir() or an existing file or directory deleted or renamed (with fs_remove() or fs_rename()). 109 600-uC-FS-001.book Page 110 Wednesday, October 10, 2012 12:03 PM Chapter 8 110 600-uC-FS-001.book Page 111 Wednesday, October 10, 2012 12:03 PM Chapter 9 Device Drivers The file system initializes, controls, reads and writes a device using a device driver. A C/FS device driver has eight interface functions, grouped into a FS_DEV_DRV structure that is registered with the file system (with FS_DevDrvAdd()) as part of application start-up, immediately following FS_Init(). Several restrictions are enforced to preserve the uniqueness of device drivers and simplify management: Each device driver must have a unique name. No driver may be registered more than once. Device drivers cannot be unregistered. All device driver functions must be implemented (even if one or more is `empty'). 111 600-uC-FS-001.book Page 112 Wednesday, October 10, 2012 12:03 PM Chapter 9 9-1 PROVIDED DEVICE DRIVERS Portable device drivers are provided for standard media categories: RAM disk driver. The RAM disk driver supports using internal or external RAM as a storage medium. SD/MMC driver. The SD/MMC driver supports SD, SD high-capacity and MMC cards, including micro and mini form factors. Either cardmode and SPI mode can be used. NAND driver. The NAND flash driver support parallel (typically ONFI-compliant) NAND flash devices. NOR driver. The NOR flash driver support parallel (typically CFI-compliant) and serial (typically SPI) NOR flash devices. MSC driver. The MSC (Mass Storage Class) driver supports USB host MSC devices (i.e., thumb drives or USB drives) via C/USB-Host. Table 9-1 summarizes the drivers, driver names and driver API structure names. If you require more information about a driver, please consult the listed chapter. Driver Driver Name Driver API Structure Name Reference RAM disk "ram:" FSDev_RAM Chapter 11, on page 131 SD/MMC "sd:" / "sdcard:" FSDev_SD_SPI / FSDev_SD_Card Chapter 12, on page 135 NAND "nand:" FSDev_NAND Chapter 13, on page 159 NOR "nor:" FSDev_NOR Chapter 14, on page 199 MSC "msc:" FSDev_MSC Chapter 15, on page 219 Table 9-1 Device driver API structures If your medium is not supported by one of these drivers, a new driver can be written based on the template driver. Appendix C, "Device Driver" on page 412 describes how to do this. 112 600-uC-FS-001.book Page 113 Wednesday, October 10, 2012 12:03 PM Provided Device Drivers 9-1-1 DRIVER CHARACTERIZATION Typical ROM requirements are summarized in Table 9-2. The ROM data were collected on IAR EWARM v6.40 with high size optimization. Driver ROM, Thumb Mode ROM, ARM Mode RAM disk 0.4 kB 0.6 kB SD/MMC CardMode* 3.9 kB 6.2 kB SD/MMC SPI* 4.7 kB 7.3 kB NOR*** 5.7 kB 9.1 kB MSC** 0.6 kB 0.9 kB Table 9-2 Driver ROM requirements * Not including BSP **Not including C/USB ***Using the generic controller and software ECC, not including BSP Typical RAM requirements are summarized in Table 9-3. 113 600-uC-FS-001.book Page 114 Wednesday, October 10, 2012 12:03 PM Chapter 9 Driver MSC* RAM (Overhead) RAM (Per Device) 12 bytes 32 bytes NOR*** 4 bytes --- bytes RAM disk 4 bytes 24 bytes SD/MMC CardMode 4 bytes 64 bytes SD/MMC SPI 4 bytes 52 bytes Table 9-3 Driver RAM requirements *Not including C/USB ***See section 14-2 "Driver & Device Characteristics" on page 202. Performance can vary significantly as a result of CPU and hardware differences, both as well as file system format. All test were compiled using IAR EWARM 6.40.1 using high speed optimization. Table 9-4 lists results for two general performance tests: Read file test. Read a file in 4-kB and 64kB chunks. The time to open the file is NOT included in the time. Write file test. Write a file in 4-kB and 64kB chunks. The time to open (create) the file is NOT included in the time. 114 600-uC-FS-001.book Page 115 Wednesday, October 10, 2012 12:03 PM Drivers comparison Performance (kB/s) Driver RAM Disk CPU Media 4k Read 64k Read 4k Write 64k Write ST STM32F207IGH6 IS61WV102416BLL-10MLI 16 622 kB/s 31 186 kB/s 120Mhz 16Mbit 10-ns SRAM 10 839 kB/s 26 473 kB/s RAM Disk Atmel AT91SAM9M10 400-Mhz MT47H64M8CF-3-F DDR2 2x8bit 2 banks interleaved 27 478 kB/s 18 858 kB/s 96 866 kB/s 84 121 kB/s SD/MMC CardMode ST STM32F207IGH6 120-MHz, 4-bit mode Nokia 64 MB SMS064FF SD Card 5 333 kB/s 661 kB/s 8 595 kB/s 1 607 kB/s SD/MMC SPI ST STM32F107VC 72-Mhz Nokia 64 MB SMS064FF SD Card 947 kB/s 444 kB/s 1 010kB/s 793 kB/s SD/MMC SPI NAND NAND (auto-sync) ST STM32F107VC Nokia 64 MB SMS064FF SD 759 kB/s 800 kB/s 72-MHz (w/CRC) Card 388 kB/s 655 kB/s Atmel AT91SAM9M10 Micron MT29F2G08ABDHC 9 039 kB/s 10 732 kB/s 400-Mhz 2Gb NAND flash 1 950 kB/s 4 332 kB/s Atmel AT91SAM9M10 Micron MT29F2G08ABDHC 9 039 kB/s 10 732 kB/s 400-Mhz 2Gb NAND flash 1 336 kB/s 2 695 kB/s NOR (parallel) ST STM32F103ZE 72-MHz ST M29W128GL 16MB NOR flash 2 750 kB/s 158 kB/s 3 810 kB/s 310 kB/s NOR (serial) ST STM32F103VE 72-MHz ST M25P64 serial flash 691 kB/s 55 kB/s ---- kB/s ---- kB/s Atmel AT91SAM9M10 64-GB SanDisk Cruzer 613 kB/s 2 301kB/s 153 kB/s 883 kB/s MSC 400-MHz Table 9-4 Driver performance (file test) 9-2 DRIVERS COMPARISON NAND flash is a low-cost on-board storage solution. Typically, NAND flash have a multiplexed bus for address and data, resulting in a much lower pin count than parallel NOR devices. Their low price-per-bit and relatively high capacities often makes these preferable to NOR, though the higher absolute cost (because the lowest-capacity devices are at least 128-Mb) reverses the logic for applications requiring very little storage. 115 600-uC-FS-001.book Page 116 Wednesday, October 10, 2012 12:03 PM Chapter 9 116 600-uC-FS-001.book Page 117 Wednesday, October 10, 2012 12:03 PM Chapter 10 FAT File System Microsoft originally developed FAT (File Allocation Table) as a simple file system for diskettes and then hard disks. FAT originally ran on very early, very small microcomputers, e.g., IBM PCs with 256 KB of memory. Windows, Mac OS, Linux, and many Unix-like systems also use FAT as a file interchange format. FAT was designed for magnetic disks, but today supports Flash memory and other storage devices. C/FS is an implementation of FAT that supports FAT12, FAT16, and FAT32. By default, C/FS supports only short (8.3) file names. To enable long file names (LFNs), you must set a configuration switch. By setting this switch, you agree to contact Microsoft to obtain a license to use LFNs. 10-1 WHY EMBEDDED SYSTEMS USE FAT Since FAT's inception, it has been extended multiple times to support larger disks as well as longer file names. However, it remains simple enough for the most resource-constrained embedded system. Because FAT is supported by all major operating systems, it still dominates the removable storage market. USB flash drives are embedded systems, and most are formatted in FAT. Cameras, MP3 players, and other consumer electronics that depend on easy file transfer to and from the device also normally use FAT. FAT is also widely used in embedded systems, especially ones that run on microcontrollers. 117 600-uC-FS-001.book Page 118 Wednesday, October 10, 2012 12:03 PM Chapter 10 10-2 ORGANIZATION OF A FAT VOLUME As shown in Figure 10-1, a FAT volume (i.e., a logical disk) contains several areas: FAT12/16 Reserved Area 1st FAT Area 2nd FAT Area FAT32 Reserved Area 1st FAT Area 2nd FAT Area Root Directory Data Area Data Area Figure 10-1 FAT volume layout 1 Reserved area. The reserved area includes the boot sector, which contains basic format information, like the number of sectors in the volume. 2 File allocation table area. The FAT file system is named after the file allocation table, a large table with one entry for each cluster in the volume. This area must contain at least one FAT area; for redundancy, it may also contain one or more additional FAT areas. 3 Root directory area. FAT 12 and FAT 16 volumes contain a fixed amount of space for the root directory, In FAT32 volumes, there is no area reserved for the root directory; the root directory is instead stored in a fixed location in the data area. 4 Data area. The data area contains files and directories. A directory (or folder) is a special type of file. FAT supports only four attributes for its files and directories: Read-Only, Hidden, System, and Archive. 118 600-uC-FS-001.book Page 119 Wednesday, October 10, 2012 12:03 PM Organization of a FAT Volume 10-2-1 ORGANIZATION OF DIRECTORIES AND DIRECTORY ENTRIES In the FAT file system, directories are just special files, composed of 32-byte structures called directory entries. The topmost directory, the root directory, is located using information in the boot sector. The normal (short file name) entries in this directory and all other directories follow the format shown below in Figure 10-2 (long file name are discussed a little further on in section 10-3-2 "Short and Long File Names" on page 123. One Directory Entry (1) Byte: 1 (2) 9 (3) (4) (5) (6) 12 13 14 15 (7) 17 (8) 19 (9) 21 (10) 23 (11) 25 (12) 27 (13) 29 32 Figure 10-2 The entry for a file in a FAT directory F10-2(1) Filename is the 8-character short file name (SFN). Eight bytes. F10-2(2) File extension is the three-character file name extension. Three bytes F10-2(3) File Attributes are the attributes of the entry, indicating whether it is a file or directory, writable or read-only and visible or hidden. One byte. F10-2(4) Reserved area. One byte. F10-2(5) Created Time (milliseconds) and is the fraction of the second of the date and time the file was created. One byte. F10-2(6) Created Time is the hour, minute, and second the file was created. Two bytes. F10-2(7) Created Date is the day, month, and year the file was created. Two bytes. F10-2(8) Last Accessed Day is the day, month, and year the file was last accessed. Two byte. 119 600-uC-FS-001.book Page 120 Wednesday, October 10, 2012 12:03 PM Chapter 10 F10-2(9) Extended Attribute Index. In FAT16, this field is used for extended attributes for some operating systems. In FAT32, this field contains the high two bytes of the cluster address. Two bytes. F10-2(10) Last Modified Time is hour, minute, and second when the file was last modified. Two bytes. F10-2(11) Last Modified Date is the day, month, and year when the file was last modified. Two bytes. F10-2(12) Cluster address is the address of the first cluster allocated to the file (i.e., the first cluster that contains file data). In FAT16, this field contains the entire cluster address. In FAT32, this field contains the low two bytes of the cluster address. Two bytes. F10-2(13) File Size is the size of the file, in octets. If the entry is a directory, this field is blank. Four bytes. 10-3 ORGANIZATION OF THE FILE ALLOCATION TABLE The File Allocation Table is a map of all the clusters that make up the data area of the volume. The FAT does not "know" the location of the first cluster that has been allocated to a given file. It does not even know the name of any files. That information is stored in the directory. As described in the section above, the directory entry for each file contains a value called a cluster address. This is a pointer to the first entry in the File Allocation Table for a given file. This FAT entry in turn points to the first cluster in the volume's data area that has been allocated to the file. If the file has been allocated more than one cluster, then the FAT table entry will contain the address of the second cluster (which is also the index number of the second cluster's entry in the FAT table). The second cluster entry points to the third, and so forth. A FAT entry like this forms a linked list commonly called a cluster chain. Figure 10-3 illustrates the relationship between the directory entry and the FAT. 120 600-uC-FS-001.book Page 121 Wednesday, October 10, 2012 12:03 PM Organization of the File Allocation Table One Directory Entry 32 bytes File Name (example: file.dat) File Allocation Table 4 bytes per entry Start-of-File Cluster (example: 40) File Size (example: 6,230) 37 38 39 40 41 42 43 44 45 46 47 48 49 50 ... 00 00 41 46 43 EOF 00 00 EOF 00 00 00 ... Figure 10-3 A directory entry points to the first entry in a cluster chain (FAT 16) In Figure 10-3, the directory entry for a file points to the 40th entry in the FAT table. The 40th entry points to the 41st, the 41st to the 46th; the 46th is not a pointer, as the entry contains a special end-of-cluster-chain marker. The means that for Figure 10-3, the 41st cluster is the final cluster allocated to the file. Other entries in the FAT area in illustrated Figure 10-3 are either not allocated to a file, or allocated to a file whose cluster chain is terminated by the 43rd entry. To summarize, a cluster's entry in the File Allocation Table typically contains a pointer to the entry for the next cluster in a file's cluster chain. Other values that can be stored in a cluster's entry in the FAT are special markers for: End-of-cluster-chain: this cluster is the final cluster for a file. Cluster-not-allocated (free cluster mark): no file is using this cluster. Damaged-cluster: this cluster cannot be used. NOTE: Updating the FAT table is time consuming, but updating it frequently is very important. If the FAT table gets out of sync with its files, files and directories can become corrupted, resulting in the loss of data (see See "Optional Journaling System" on page 127.). 121 600-uC-FS-001.book Page 122 Wednesday, October 10, 2012 12:03 PM Chapter 10 10-3-1 FAT12 / FAT16 / FAT32 The earliest version of FAT, the file system integrated into MS-DOS, is now called FAT12, so-called because each cluster address in the File Allocation Table is 12 bits long. This limits disk size to approximately 32 MB. Extensions to 16- and 32-bit addresses (i.e., FAT16 and FAT32), expand support to 2 GB and 8 TB, respectively. Pointer size Max. size Free cluster Damaged End of cluster (Table entry size) of disk marker cluster marker chain marker FAT12 12 bits 32 MB 0 0xff7 0xff8 FAT16 16 bits 2 GB 0 0xfff7 0xfff8 FAT32 32 bits 8 TB 0 0x0fff fff7 0x0fff fff8 FAT version In C/FS, you can enable support for FAT12, FAT16 and FAT32 individually: this means that you can enable only the FAT version that you need for your embedded system (see Appendix E, "C/FS Configuration" on page 497. FAT32 introduced some innovations: The root directory in the earlier systems was a fixed size; i.e., when the medium is formatted, the maximum number of files that could be created in the root directory (typically 512) is set. In FAT32, the root directory is dynamically resizable, like all other directories. Two special sectors have been added to the volume: the FS info sector and the backup boot sector. The former stores information convenient to the operation of the host, such as the last used cluster. The latter is a copy of the first disk sector (the boot sector), in case the original is corrupted. 122 600-uC-FS-001.book Page 123 Wednesday, October 10, 2012 12:03 PM Organization of the File Allocation Table 10-3-2 SHORT AND LONG FILE NAMES In the original version of FAT, files could only carry short "8 dot 3" names, with eight or fewer characters in the main name and three or fewer in its extension. The valid characters in these names are letters, digits, characters with values greater than 0xFF and the following: $ % ` - _ @ ~ ! ( ) { } ^ # & In C/FS, the name passed by the application is always verified, both for invalid length and invalid characters. If valid, the name is converted to upper case for storage in the directory entry. Accordingly, FAT file names are not case-sensitive. Later, in a backwards-compatible extension, Microsoft introduced long file names (LFN). LFNs are limited to 255 characters stored as 16-bit Unicode in long directory entries. Each LFN is stored with a short file name (SFN) created by truncating the LFN and attaching a numeric "tail" to the original; this results in names like "file~1.txt". In addition to the characters allowed in short file names (SFN), the following characters are allowed in LFNs: + , ; = [ ] As described in section E-7 "FAT Configuration" on page 505, support for LFNs can be disabled, if desired. If LFNs are enabled, the application may choose to specify file names in UTF-8 format, which will be converted to 16-bit Unicode for storage in directory entries. This option is available if FS_CFG_UTF8_EN is DEF_ENABLED (see Appendix E, "Feature Inclusion Configuration" on page 500). 123 600-uC-FS-001.book Page 124 Wednesday, October 10, 2012 12:03 PM Chapter 10 ENTRIES FOR FILES THAT HAVE LONG FILE NAMES To allow FAT to support long file names, Microsoft devised the LFN directory entry, as shown in Figure 10-4. Figure 10-4 LFN directory entry An LFN entry is essentially a workaround to store long file names in several contiguous 32-byte entries that were originally intended for short file names. A file with an LFN also has a SFN this is derived from the LFN. The last block of an LFN stores the SFN that corresponds to the LFN. The two or more preceding blocks each store parts of the LFN. Figure 10-4 shows four "blocks" The first block shows the names for the fields in an LFN entry; the actual LFN entry is shown in the next three blocks. The middle two blocks show how FAT stores the LFN for a file named "abcdefghijklm.op" in two 32-byte FAT table entries. 124 600-uC-FS-001.book Page 125 Wednesday, October 10, 2012 12:03 PM Organization of the File Allocation Table The final block shows how FAT stores the SFN derived from the LFN. In this case, the SFN is "abcdef~1.op" Note that the "." of an 8.3 filename is not actually stored. The final 32 bytes for an LFN entry has the same fields as the 32-byte entry for (in this example) a file with a SFN of "abcdef~1.op". Accordingly, it is able to store, in addition to the file's SFN, the properties (creation date and time, etc.) for file "abcdefghijklm.op". Together, the three blocks make up one LFN directory entry, in this case the LFN entry for file "abcdefghijklm.op". A long file name is stored in either two or three 32-bit entries of a directory table: If three entries are needed to store the long file name, byte 0 of the entries carry order numbers of 0x43, 0x02 and 0x01, respectively. (Byte 0 is labelled "Ord" in Figure 10-4). None of these, are valid characters (which allows backward compatibility). If two entries are needed (as in Figure 10-4), byte 0 of the entries carry order numbers of 0x43 and 0x01, respectively. In entries that store part of a LFN, byte 11, where the Attributes value is stored in a SFN, is always 0x0F; Microsoft found that no software would modify or use a directory entry with this marker. In entries that store part of a LFN, byte 13 contains the checksum, which is calculated from the SFN. FAT's file system software recalculates the checksum each time it parses the directory entries. If the stored checksum is not the same as the recalculated checksum, FAT's file system software knows that the SFN was modified (presumably by a program that is not LFN-aware). 125 600-uC-FS-001.book Page 126 Wednesday, October 10, 2012 12:03 PM Chapter 10 10-4 FORMATTING A volume, once it is open, may need to be formatted before files or directories can be created. The default format is selected by passing a NULL pointer as the second parameter of FSVol_Fmt(). Alternatively, the exact properties of the file system can be configured with a FS_FAT_SYS_CFG structure. An example of populating and using the FAT configuration is shown in Listing 10-1. If the configuration is invalid, an error will be returned from FSVol_Fmt(). For more information about the FS_FAT_SYS_CFG structure, see Appendix D, "FS_FAT_SYS_CFG" on page 492. void App_InitFS (void) { FS_ERR err; FS_FAT_SYS_CFG fat_cfg; . . . fat_cfg.ClusSize = 4; fat_cfg.RsvdAreaSize = 1; fat_cfg.RootDirEntryCnt = 512; fat_cfg.FAT_Type = 12; fat_cfg.NbrFATs = 2; FSVol_Fmt("ram:0:", &fat_cfg, &err); if (err != FS_ERR_NONE) { APP_TRACE_DEBUG(("Format failded.\r\n")); } . . . } /* /* /* /* /* Cluster size = 4 * 512-B = 2-kB.*/ Reserved area = 1 sector. */ Entries in root dir = 512. */ FAT type = FAT12. */ Number of FATs = 2. */ Listing 10-1 Example device format 126 600-uC-FS-001.book Page 127 Wednesday, October 10, 2012 12:03 PM Sources of Corruption in FAT Volumes 10-5 SOURCES OF CORRUPTION IN FAT VOLUMES Errors may accrue on a FAT volume, either by device removal during file system modifications, power loss, or by improper host operation. Several corruptions are common: Cross-linked files. If a cluster becomes linked to two files, then it is called "cross-linked". The only way to resolve this is by deleting both files; if necessary, they can be copied first so that the contents can be verified. Orphaned directory entries. If LFNs are used, a single file name may span several directory entries. If a file deletion is interrupted, some of these may be left behind or "orphaned" to be deleted later. Invalid cluster. The cluster specified in a directory entry or linked in a chain may be invalid. The only recourse is to zero the cluster (if in a directory entry) or replace with end-of-cluster (if in a chain). Chain length mismatch. Too many or too few clusters may be linked to a file, compared to its size. If too many, the extra clusters should be freed. If too few, the file size should be adjusted. Lost cluster. A lost cluster is marked as allocated in the FAT, but is not linked to any file. Optionally, lost cluster chains may be recovered to a file. 10-6 OPTIONAL JOURNALING SYSTEM Since cluster allocation information is stored separately from file information and directory entries, even file operations that make a simple change to one file (e.g., adding data to the end of a file, updating data in place) are non-atomic. An atomic operation is made up of a set of sub-operations which must all be completed; the atomic operation is completed successfully only if all the sub-operations complete successfully. The repercussions can be innocuous (e.g., wasted disk space) or very serious: corrupted directories, corrupted files, and lost data (see section 10-5 "Sources of Corruption in FAT volumes" on page 127). 127 600-uC-FS-001.book Page 128 Wednesday, October 10, 2012 12:03 PM Chapter 10 One way that C/FS reduces the risk of corruption by ordering modifications wisely, for example, by forcing an update to the FAT after every Write operation. It also has an optional journaling system that allows you to log data about impending and completed changes to files and directories. Without the journaling system, any atomic operation, even a single Write operation (at the API level), can be interrupted by a power failure or a crash of the application or the operating system. Accordingly, FAT file systems without journaling are not fail-safe. Journaling means that a file system logs all changes to a journal before committing them to the main file system. Each file system operation is then in fact done twice. Journaling protects the file system at the expense of time. Data can be lost in case of unexpected Reset in either the File System Layer or in the Device Driver Layer. Your entire system is fail-safe only if both layers are fail-safe. The journaling add-on makes the file system layer fail-safe. Your entire system is only fail-safe if the driver layer is fail-safe as well. The device drivers supplied with C/FS are each fail-safe, as the chapter for each specific driver shows. 128 600-uC-FS-001.book Page 129 Wednesday, October 10, 2012 12:03 PM Licensing Issues 10-7 LICENSING ISSUES There are licensing issues related to FAT, particularly relating to Microsoft patents that deal with long file names (LFNs). 10-7-1 LICENSES FOR LONG FILE NAMES (LFNS) Microsoft announced on 2003-12-03 that it would be offering licenses for use of its FAT specification and "associated intellectual property". The royalty for using LFNs is US $0.25 royalty per unit sold, with a maximum of US $250,000 per license agreement. Micrium C/FS is delivered with complete source code for FAT; this includes source code for LFNs. To enable long file names (LFNs), you must set a configuration switch. By setting this switch, you agree to contact Microsoft to obtain a license to use LFNs. 10-7-2 EXTENDED FILE ALLOCATION TABLE (EXFAT) Microsoft has developed a new, proprietary file system: exFAT, also known as FAT64. exFAT was designed to handle very large storage media. Microsoft requires a license to make or distribute implementations of exFAT. Micrium does not offer exFAT in C/FS at this time. 129 600-uC-FS-001.book Page 130 Wednesday, October 10, 2012 12:03 PM Chapter 10 130 600-uC-FS-001.book Page 131 Wednesday, October 10, 2012 12:03 PM Chapter 11 RAM Disk Driver The simplest device driver is the RAM disk driver, which uses a block of memory (internal or external) as a storage medium. 11-1 FILES AND DIRECTORIES The files inside the RAM disk driver directory are outlined in this section; the generic file-system files, outlined in Chapter 3, "C/FS Directories and Files" on page 29, are also required. \Micrium\Software\uC-FS\Dev This directory contains device-specific files. \Micrium\Software\uC-FS\Dev\RAMDisk This directory contains the RAM disk driver files. fs_dev_ramdisk.* constitute the RAM disk device driver. 131 600-uC-FS-001.book Page 132 Wednesday, October 10, 2012 12:03 PM Chapter 11 11-2 USING THE RAM DISK DRIVER To use the RAM disk driver, two files, in addition to the generic FS files, must be included in the build: fs_dev_ramdisk.c. fs_dev_ramdisk.h. The file fs_dev_ramdisk.h must also be #included in any application or header files that directly reference the driver (for example, by registering the device driver). The following directory must be on the project include path: \Micrium\Software\uC-FS\Dev\RAMDisk A single RAM disk is opened as shown in . The file system initialization (FS_Init()) function must have previously been called. ROM/RAM characteristics and performance benchmarks of the RAM disk driver can be found in section 9-1-1 "Driver Characterization" on page 113. For more information about the FS_DEV_RAM_CFG structure, see section D-4 "FS_DEV_RAM_CFG" on page 488. #define APP_CFG_FS_RAM_SEC_SIZE 512 /* (1) */ #define APP_CFG_FS_RAM_NBR_SECS (48 * 1024) static CPU_INT32U App_FS_RAM_Disk[APP_CFG_FS_RAM_SEC_SIZE * APP_CFG_FS_RAM_NBR_SECS / 4]; CPU_BOOLEAN App_FS_AddRAM (void) { FS_ERR err; FS_DEV_RAM_CFG cfg; FS_DevDrvAdd((FS_DEV_API *)&FSDev_RAM, /* (2) */ (FS_ERR *)&err); if ((err != FS_ERR_NONE) && (err != FS_ERR_DEV_DRV_ALREADY_ADDED)) { return (DEF_FAIL); } ram_cfg.SecSize = APP_CFG_FS_RAM_SEC_SIZE; /* (3) */ ram_cfg.Size = APP_CFG_FS_RAM_NBR_SECS; ram_cfg.DiskPtr = (void *)&App_FS_RAM_Disk[0] 132 600-uC-FS-001.book Page 133 Wednesday, October 10, 2012 12:03 PM Using the RAM Disk Driver /* (4) FSDev_Open((CPU_CHAR *)"ram:0:", (void *)&ram_cfg, (FS_ERR *)&err); if (err != FS_ERR_NONE) { return (DEF_FAIL); } FSVol_Open((CPU_CHAR *)"ram:0:", (CPU_CHAR *)"ram:0:", (FS_PARTITION_NBR ) 0, (FS_ERR *)&err); /* /* */ (a) */ (b) */ /* (5) /* (a) /* (b) /* (c) */ */ */ */ switch (err) { case FS_ERR_NONE: APP_TRACE_DBG((" ...opened volume (mounted).\r\n")); break; case FS_ERR_PARTITION_NOT_FOUND: /* Volume error. */ APP_TRACE_DBG((" ...opened device (not formatted).\r\n")); FSVol_Fmt("ram:0:", (void *)0, &err); if (err != FS_ERR_NONE) { APP_TRACE_DBG((" return (DEF_FAIL); } break; default: APP_TRACE_DBG((" return (DEF_FAIL); /* (6) */ ...format failed.\r\n")); /* Device error. */ ...opening volume failed w/err = %d.\r\n\r\n", err)); } return (DEF_OK); } Listing 11-1 Opening a RAM disk volume L11-1(1) The sector size and number of sectors in the RAM disk must be defined. The sector size should be 512, 1024, 2048 or 4096; the number of sectors will be determined by your application requirements. This defines a 24-MB RAM disk (49152 512-B sectors). On most CPUs, it is beneficial to 32-bit align the RAM disk, since this will speed up access. L11-1(2) Register the RAM disk driver FSDev_RAM. L11-1(3) The RAM disk parameters--sector size, size (in sectors) and pointer to the disk--should be assigned to a FS_DEV_RAM_CFG structure. 133 600-uC-FS-001.book Page 134 Wednesday, October 10, 2012 12:03 PM Chapter 11 L11-1(4) FSDev_Open() opens/initializes a file system device. The parameters are the device name (3a) and a pointer to a device driver-specific configuration structure (3b). The device name (3a) s composed of a device driver name ("ram"), a single colon, an ASCII-formatted integer (the unit number) and another colon. L11-1(5) FSVol_Open() opens/mounts a volume. The parameters are the volume name (5a), the device name (5b) and the partition that will be opened (5c). There is no restriction on the volume name (5a); however, it is typical to give the volume the same name as the underlying device. If the default partition is to be opened, or if the device is not partition, then the partition number (5c) should be zero. L11-1(6) FSVol_Fmt() formats a file system volume. If the RAM disk is in volatile RAM, it have no file system on it after it is opened (it will be unformatted) and must be formatted before a volume on it is opened. If the RAM disk initialization succeeds, the file system will produce the trace output as shown in Figure 11-1 (if a sufficiently high trace level is configured). See section E-9 "Trace Configuration" on page 507 about configuring the trace level. Figure 11-1 RAM disk initialization trace output 134 600-uC-FS-001.book Page 135 Wednesday, October 10, 2012 12:03 PM Chapter 12 SD/MMC Drivers SD (Secure Digital) cards and MMCs (MultiMedia Cards) are portable, low-cost media often used for storage in consumer devices. Six variants, as shown in Table 12-1, are widely available to electronic retail outlets, all supported by SD/MMC driver. The MMCplus and SD or SDHC are offered in compatible large card formats. Adapters are offered for the remaining devices so that these can fit in standard SD/MMC card slots. Two further products incorporating SD/MMC technology are emerging. First, some cards now integrate both USB and SD/MMC connectivity, for increased ease-of-access in both PCs and embedded devices. The second are embedded MMC (trademarked eMMC), fixed flash-based media addressed like MMC cards. 135 600-uC-FS-001.book Page 136 Wednesday, October 10, 2012 12:03 PM Chapter 12 Card MMCPlus Size Pin Count 32 x 24 x 1.4 mm 13 Description Most current MMC cards can operate with 1, 4 or 8 data lines, though legacy media were limited to a single data line. The MMCmobile 18 x 24 x 1.4 mm 13 maximum clock frequency is 20 MHz, providing for maximum theoretical transfer speeds of 20 MB/s, 80 MB/s and 160 MB/s for the three possible bus widths. MMCmicro 14 x 12 x 1.1 mm 13 SD or SDHC 32 x 24 x 1.4 mm 9 SD cards can operate in cardmode with 1 or 4 data lines or in SPI mode. The maximum SDmini 21.5 x 20 x 1.4 mm 11 clock frequency is 25 MHz, providing for maximum theoretical transfer speeds of 25 MHz and 50 MHz for the two possible bus widths. SDmicro 15 x 11 x 1.0 mm 8 Table 12-1 SD/MMC devices SD/MMC cards can be used in two modes: card mode (also referred to as MMC mode and SD mode) and SPI mode. The former offers up to 8 data lines (depending on the type of card); the latter, only one data line, but the accessibility of a communication bus common on many MCUs/MPUs. Because these modes involve different command protocols, they require different drivers. 136 600-uC-FS-001.book Page 137 Wednesday, October 10, 2012 12:03 PM Files and Directories 12-1 FILES AND DIRECTORIES The files inside the SD/MMC driver directory is outlined in this section; the generic file-system files, outlined in Chapter 3, "C/FS Directories and Files" on page 29, are also required. \Micrium\Software\uC-FS\Dev This directory contains device-specific files. \Micrium\Software\uC-FS\Dev\SD This directory contains the SD/MMC driver files. fs_dev_sd.* contain functions and definitions required for both SPI and card modes. \Micrium\Software\uC-FS\Dev\SD\Card This directory contains the SD/MMC driver files for card mode. fs_dev_sd_card.* are device driver for SD/MMC cards using card mode. This file requires a set of BSP functions be defined in a file named fs_dev_sd_card_bsp.c to work with a certain hardware setup. .\BSP\Template\fs_dev_sd_card_bsp.c is a template BSP. See section C-5 "SD/MMC Cardmode BSP" on page 425 for more information. \Micrium\Software\uC-FS\Dev\SD\SPI This directory contains the SD/MMC driver files for SPI mode. fs_dev_sd_spi.* are device driver for SD/MMC cards using SPI mode. This file requires a set of BSP functions be defined in a file named fs_dev_sd_spi_bsp.c to work with a certain hardware setup. .\BSP\Template\fs_dev_sd_spi_bsp.c is a template BSP. See section C-6 "SD/MMC SPI mode BSP" on page 452 for more information. .\BSP\Template (GPIO)\fs_dev_sd_spi_bsp.c is a template GPIO (bit-banging) BSP. See section C-6 "SD/MMC SPI mode BSP" on page 452 for more information. 137 600-uC-FS-001.book Page 138 Wednesday, October 10, 2012 12:03 PM Chapter 12 \Micrium\Software\uC-FS\Examples\BSP\Dev\SD\Card Each subdirectory contains an example BSP for a particular platform. These are named according to the following rubric: <Chip Manufacturer>\<Board or CPU>\fs_dev_sd_card_bsp.c \Micrium\Software\uC-FS\Examples\BSP\Dev\SD\SPI Each subdirectory contains an example BSP for a particular platform. These are named according to the following rubric: <Chip Manufacturer>\<Board or CPU>\fs_dev_sd_spi_bsp.c 12-2 USING THE SD/MMC CARDMODE DRIVER To use the SD/MMC cardmode driver, five files, in addition to the generic file system files, must be included in the build: fs_dev_sd.c. fs_dev_sd.h. fs_dev_sd_card.c. fs_dev_sd_card.h. fs_dev_sd_card_bsp.c. The file fs_dev_sd_card.h must also be #included in any application or header files that directly reference the driver (for example, by registering the device driver). The following directories must be on the project include path: \Micrium\Software\uC-FS\Dev\SD \Micrium\Software\uC-FS\Dev\SD\Card 138 600-uC-FS-001.book Page 139 Wednesday, October 10, 2012 12:03 PM Using the SD/MMC CardMode Driver A single SD/MMC volume is opened as shown in Listing 12-1. The file system initialization (FS_Init()) function must have previously been called. ROM/RAM characteristics and performance benchmarks of the SD/MMC driver can be found in section 9-1-1 "Driver Characterization" on page 113. The SD/MMC driver also provides interface functions to get low-level card information and read the Card ID and Card-Specific Data registers (see section A-12 "FAT System Driver Functions" on page 386). CPU_BOOLEAN { FS_ERR App_FS_AddSD_Card (void) err; FS_DevDrvAdd((FS_DEV_API *)&FSDev_SD_Card, /* (1) */ (FS_ERR *)&err); if ((err != FS_ERR_NONE) && (err != FS_ERR_DEV_DRV_ALREADY_ADDED)) { return (DEF_FAIL); } /* (2) */ FSDev_Open((CPU_CHAR *)"sdcard:0:", /* (a) */ (void *) 0, /* (b) */ (FS_ERR *)&err); switch (err) { case FS_ERR_NONE: break; case case case case FS_ERR_DEV: FS_ERR_DEV_IO: FS_ERR_DEV_TIMEOUT: FS_ERR_DEV_NOT_PRESENT: return (DEF_FAIL); default: return (DEF_FAIL); } FSVol_Open((CPU_CHAR *)"sdcard:0:", (CPU_CHAR *)"sdcard:0:", (FS_PARTITION_NBR ) 0, (FS_ERR *)&err); /* (3) /* (a) /* (b) /* (c) */ */ */ */ 139 600-uC-FS-001.book Page 140 Wednesday, October 10, 2012 12:03 PM Chapter 12 switch (err) { case FS_ERR_NONE: APP_TRACE_DBG((" ...opened volume (mounted).\r\n")); break; case FS_ERR_DEV: case FS_ERR_DEV_IO: case FS_ERR_DEV_TIMEOUT: case FS_ERR_DEV_NOT_PRESENT: case FS_ERR_PARTITION_NOT_FOUND: APP_TRACE_DBG((" ...opened device (unmounted).\r\n")); return (DEF_FAIL); default: APP_TRACE_DBG((" ...opening volume failed w/err = %d.\r\n\r\n", err)); return (DEF_FAIL); } return (DEF_OK); } Listing 12-1 Opening a SD/MMC device volume L12-1(1) Register the SD/MMC CardMode device driver FSDev_SD_Card. L12-1(2) FSDev_Open() opens/initializes a file system device. The parameters are the device name (1a) and a pointer to a device driver-specific configuration structure (1b). The device name (1a) is composed of a device driver name ("sdcard"), a single colon, an ASCII-formatted integer (the unit number) and another colon. Since the SD/MMC CardMode driver requires no configuration, the configuration structure (1b) should be passed a NULL pointer. Since SD/MMC are often removable media, it is possible for the device to not be present when FSDev_Open() is called. The device will still be added to the file system and a volume opened on the (not yet present) device. When the volume is later accessed, the file system will attempt to refresh the device information and detect a file system (see section 5-2 "Using Devices" on page 69 for more information). L12-1(3) 140 FSVol_Open() opens/mounts a volume. The parameters are the volume name (2a), the device name (2b) and the partition that will be opened (2c). There is no restriction on the volume name (2a); however, it is typical to give the volume the same name as the underlying device. If the default partition is to be opened, or if the device is not partitioned, then the partition number (2c) should be zero. 600-uC-FS-001.book Page 141 Wednesday, October 10, 2012 12:03 PM Using the SD/MMC CardMode Driver If the SD/MMC initialization succeeds, the file system will produce the trace output as shown in Figure 12-1 (if a sufficiently high trace level is configured). See section E-9 "Trace Configuration" on page 507 about configuring the trace level. Figure 12-1 SD/MMC detection trace output 12-2-1 SD/MMC CARDMODE COMMUNICATION In card mode, seven, nine or thirteen pins on the SD/MMC device are used, with the functions listed in the table below. All cards start up in "1 bit" mode (upon entering identification mode), which involves only a single data line. Once the host (the MCU/MPU) discovers the capabilities of the card, it may initiate 4- or 8-bit communication (the latter available only on new MMCs). Some card holders contain circuitry for card detect and write protect indicators, which the MCU/MPU may also monitor. Pin Name Type Description 1 CD/DAT3 I/O Card Detect/Data Line (Bit 3) 2 CMD I/O Command/Response 3 Vss1 S Supply voltage ground 4 VDD S Supply voltage 5 CLK I Clock 6 VSS2 S Supply voltage ground 7 DAT0 I/O Data Line (Bit 0) 141 600-uC-FS-001.book Page 142 Wednesday, October 10, 2012 12:03 PM Chapter 12 Pin Name Type Description 8 DAT1 I/O Data Line (Bit 1) 9 DAT2 I/O Data Line (Bit 2) 10 DAT4 I/O Data Line (Bit 4)* 11 DAT5 I/O Data Line (Bit 5)* 12 DAT6 I/O Data Line (Bit 6)* 13 DAT7 I/O Data Line (Bit 7)* Table 12-2 SD/MMC pinout (Card mode) *Only present in MMC cards. Exchanges between the host and card begin with a command (sent by the host on the CMD line), often followed by a response from the card (also on the CMD line); finally, one or more blocks data may be sent in one direction (on the data line(s)), each appended with a CRC. DAT Card-to-host Command Respose (5) (6) (1) Card-to-host (read) Host-to-card (write) (write only) Data CRC CMD Host-to-card Busy (2) (3) (4) Figure 12-2 SD/MMC communication sequence F12-2(1) When no data is being transmitted, data lines are held low. F12-2(2) Data block is preceded by a start bit (`0'); an end bit (`1') follows the CRC. F12-2(3) The CRC is the 16-bit CCITT CRC. F12-2(4) During the busy signaling following a write, DAT0 only is held low. F12-2(5) See Figure 12-3 for description of the command format. F12-2(6) See Figure 12-3 for description of the command format. 142 600-uC-FS-001.book Page 143 Wednesday, October 10, 2012 12:03 PM Using the SD/MMC CardMode Driver Start bit Transmission bit Command format 01 Cmd ix 6 bits End bit Argument 32 bits CRC 7 bits 1 CRC 7 bits 1 Start bit Transmission bit Response format 00 Cmd ix 6 bits End bit Response 32 or 128 bits (1) (2) Figure 12-3 SD/MMC command and response formats F12-3(1) Command index is not valid for response formats R2 and R3. F12-3(2) CRC is not valid for response format R3. When a card is first connected to the host (at card power-on), it is in the `inactive' state, awaiting a GO_IDLE_STATE command to start the initialization process, which is dependent on the card type. During initialization, the card starting in the `idle' state moves through the `ready' (as long as it supports the voltage range specified by the host) and `identification' states (if it is assigned an address by or is assigned an address) before ending up in `standby'. It can now get selected by the host for data transfers. Figure 15-9 flowcharts this procedure. 143 600-uC-FS-001.book Page 144 Wednesday, October 10, 2012 12:03 PM Chapter 12 12-2-2 SD/MMC CARDMODE COMMUNICATION DEBUGGING The SD/MMC cardmode driver accesses the hardware through a port (BSP). A new BSP developed according to MCU/MPU documentation or by example must be verified step-by-step until flawless operation is achieved: 1 Initialization (1-bit). Initialization must succeed for a SD/MMC card in 1-bit mode. 2 Initialization (4- or 8-bit). Initialization must succeed for a SD/MMC card in 4 or 8-bit mode. 3 Read data. Data must be read from card, in both single- and multiple-block transactions. 4 Write data. Data must be written to the card, in both single and multiple-block transactions, and subsequently verified (by reading the modified sectors and comparing to the intended contents). The (1-bit) initialization process reveals that commands can be executed and responses are returned with the proper bits in the correct byte-order. Example responses for each step in the sequence are given in Figure 12-5 and Figure 12-6. The first command executed, GO_IDLE_STATE, never receives a response from the card. Only V2 SD cards respond to SEND_IF_COND, returning the check pattern sent to the card and the accepted voltage range. The OCR register, read with SD_SEND_OP_COND or SEND_OP_COND, assumes basically the same format for all card types. Finally, the CID (card ID) and CSD (card-specific data) registers are read--the only times `long' (132-bit) responses are returned. Multiple-bit initialization (often 4-bit) when performed on a SD card further confirms that the 8-byte SCR register and 64-byte SD status can be read and that the bus width can be set in the BSP. Though all current cards support 4-bit mode operation, the SD_BUS_WIDTHS field of the SCR is checked before configure the card bus width. Afterwards, the 64-byte SD status is read to see whether the bus width change was accomplished. When first debugging a port, it may be best to force multi-bit operation disabled by returning 1 from the BSP function FSDev_SD_Card_BSP_GetBusWidthMax(). 144 600-uC-FS-001.book Page 145 Wednesday, October 10, 2012 12:03 PM Using the SD/MMC CardMode Driver GO_IDLE_STATE Invalid command SEND_IF_COND Inactive state Power On (1) Valid command (2) SD_SEND_OP_COND SD_SEND_OP_COND (3) (3) SEND_OP_COND Idle State Invalid command READ_OCR (4) (5) READ_OCR No (5) V2.0+ Standard Capacity SD card V2.0+ High Capacity SD card SEND_CID (6) Ready State V1.x Standard Capacity SD card Yes SEND_CSD (7) Standby State MMC CCS in response? Figure 12-4 Simplified SD/MMC cardmode initialization and state transitions 145 600-uC-FS-001.book Page 146 Wednesday, October 10, 2012 12:03 PM Chapter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igure 12-5 Command responses (SD card) 146 600-uC-FS-001.book Page 147 Wednesday, October 10, 2012 12:03 PM Using the SD/MMC CardMode Driver Command Response GO_IDLE_STATE No response Fig 15-6 (1) Card power May not be 1 on initial reading(s) up status SEND_OP_COND Fig 15-6 (4) 1 Reserved 0x00 7 bits VDD Voltage Window 0xFF8000 24 bits OCR 127 MID Example OID 0x1EFFFF4D 0x4D432020 0x20105E60 0x21BA5B7E PNM PRV 63 PSN MDT ALL_SEND_CID Fig 15-6 (5) CRC MID = Manufacturer ID = 0x1E OID = OEM/Application ID = 0xFFFF PNM = Product name = 0x4D4D43202020 = "MMC " PRV = Product revision = 0x10 = 1.0 PSN = Product serial number = 0x5E6021BA MDT = Manufacturing date = 0x5B Examples 127 SEND_CSD TAAC NSAC TRAN_SPEED CCC Fig 15-6 (6) C_SIZE 63 CRC 0x902F002A 0x1F5A83C7 0x6DB79FFF 0x9680000E Figure 12-6 Command responses (MMC card) SD_BUS_WIDTHS Bit 0 = 1-bit Bit 2 = 4-bit 7 3 Figure 12-7 SD SCR register 147 600-uC-FS-001.book Page 148 Wednesday, October 10, 2012 12:03 PM Chapter 12 DAT_BUS_WIDTH 0x0000 = Regular rd/wr card 00b = 1-bit 01b = 4-bit 511 SD_CARD_TYPE SIZE_OF_PROTECTED_AREA CLASS 447 ERASE_ SIZE 383 SPEED_CLASS 0x00 = Class 0 0x01 = Class 2 0x02 = Class 3 0x03 = Class 4 Figure 12-8 SD status 12-2-3 SD/MMC CARDMODE BSP OVERVIEW A BSP is required so that the SD/MMC cardmode driver will work on a particular system. The functions shown in the table below must be implemented. Pleaser refer to section C-5 "SD/MMC Cardmode BSP" on page 425 for the details about implementing your own BSP. Function Description FSDev_SD_Card_BSP_Open() Open (initialize) SD/MMC card interface. FSDev_SD_Card_BSP_Close() Close (uninitialize) SD/MMC card interface. FSDev_SD_Card_BSP_Lock() Acquire SD/MMC card bus lock. FSDev_SD_Card_BSP_Unlock() Release SD/MMC card bus lock. FSDev_SD_Card_BSP_CmdStart() Start a command. FSDev_SD_Card_BSP_CmdWaitEnd() Wait for a command to end and get response. FSDev_SD_Card_BSP_CmdDataRd() Read data following command. FSDev_SD_Card_BSP_CmdDataWr() Write data following command. FSDev_SD_Card_BSP_GetBlkCntMax() Get max block count. FSDev_SD_Card_BSP_GetBusWidthMax() Get maximum bus width, in bits. FSDev_SD_Card_BSP_SetBusWidth() Set bus width. FSDev_SD_Card_BSP_SetClkFreq() Set clock frequency. 148 600-uC-FS-001.book Page 149 Wednesday, October 10, 2012 12:03 PM Using the SD/MMC CardMode Driver Function Description FSDev_SD_Card_BSP_SetTimeoutData() Set data timeout. FSDev_SD_Card_BSP_SetTimeoutResp() Set response timeout Table 12-3 SD/MMC cardmode BSP functions The Open()/Close() functions are called upon open/close or medium change; these calls are always matched. The status and information functions (GetBlkCntMax(), GetBusWidthMax(), SetBusWidth(), SetClkFreq(), SetTimeoutData(), SetTimeoutResp()) help configure the new card upon insertion. Lock() and Unlock() surround all card accesses. The remaining functions (CmdStart(), CmdWaitEnd(), CmdDataRd(), CmdDataWr()) constitute the command execution state machine (see Figure 12-9). A return error from one of the functions will abort the state machine, so the requisite considerations, such as preparing for the next command or preventing further interrupts, must be first handled. Start command execution FSDev_SD_Card_BSP_CmdStart() Wait for command to execute and response to be returned FSDev_SD_Card_BSP_CmdWaitEnd() Write Data? FSDev_SD_Card_BSP_CmdDataWr() Error returned Return Error returned Return Read FSDev_SD_Card_BSP_CmdDataRd() Return Figure 12-9 Command execution 149 600-uC-FS-001.book Page 150 Wednesday, October 10, 2012 12:03 PM Chapter 12 12-3 USING THE SD/MMC SPI DRIVER To use the SD/MMC SPI driver, five files, in addition to the generic file system files, must be included in the build: fs_dev_sd.c fs_dev_sd.h fs_dev_sd_spi.c fs_dev_sd_spi.h fs_dev_sd_spi_bsp.c The file fs_dev_sd_spi.h must also be #included in any application or header files that directly reference the driver (for example, by registering the device driver). The following directories must be on the project include path: \Micrium\Software\uC-FS\Dev\SD \Micrium\Software\uC-FS\Dev\SD\SPI A single SD/MMC volume is opened as shown in Listing 12-2. The file system initialization (FS_Init()) function must have previously been called. ROM/RAM characteristics and performance benchmarks of the SD/MMC driver can be found in section 9-1-1 "Driver Characterization" on page 113. The SD/MMC driver also provides interface functions to get low-level card information and read the Card ID and Card-Specific Data registers (see section A-12 "FAT System Driver Functions" on page 386). FS_ERR App_FS_AddSD_SPI (void) { FS_ERR err; FS_DevDrvAdd((FS_DEV_API *)&FSDev_SD_SPI, /* (1) */ (FS_ERR *)&err); if ((err != FS_ERR_NONE) && (err != FS_ERR_DEV_DRV_ALREADY_ADDED)) { return (DEF_FAIL); } 150 600-uC-FS-001.book Page 151 Wednesday, October 10, 2012 12:03 PM Using the SD/MMC SPI Driver /* (2) FSDev_Open((CPU_CHAR *)"sd:0:", (void *) 0, (FS_ERR *)&err); /* /* */ (a) */ (b) */ switch (err) { case FS_ERR_NONE: break; case case case case FS_ERR_DEV: FS_ERR_DEV_IO: FS_ERR_DEV_TIMEOUT: FS_ERR_DEV_NOT_PRESENT: return (DEF_FAIL); default: return (DEF_FAIL); } FSVol_Open((CPU_CHAR *)"sd:0:", (CPU_CHAR *)"sd:0:", (FS_PARTITION_NBR ) 0, /* (3) /* (a) /* (b) /* (c) */ */ */ */ (FS_ERR *)&err); switch (err) { case FS_ERR_NONE: APP_TRACE_DBG((" ...opened volume (mounted).\r\n")); break; case FS_ERR_DEV: case FS_ERR_DEV_IO: case FS_ERR_DEV_TIMEOUT: case FS_ERR_DEV_NOT_PRESENT: case FS_ERR_PARTITION_NOT_FOUND: APP_TRACE_DBG((" ...opened device (unmounted).\r\n")); return (DEF_FAIL); default: APP_TRACE_DBG((" ...opening volume failed w/err = %d.\r\n\r\n", err)); return (DEF_FAIL); } return (DEF_OK); } Listing 12-2 Opening a SD/MMC device volume L12-2(1) Register the SD/MMC SPI device driver FSDev_SD_SPI. 151 600-uC-FS-001.book Page 152 Wednesday, October 10, 2012 12:03 PM Chapter 12 L12-2(2) FSDev_Open() opens/initializes a file system device. The parameters are the device name (1a) and a pointer to a device driver-specific configuration structure (1b). The device name (1a) is composed of a device driver name ("sd"), a single colon, an ASCII-formatted integer (the unit number) and another colon. Since the SD/MMC SPI driver requires no configuration, the configuration structure (1b) should be passed a NULL pointer. Since SD/MMC are often removable media, it is possible for the device to not be present when FSDev_Open() is called. The device will still be added to the file system and a volume opened on the (not yet present) device. When the volume is later accessed, the file system will attempt to refresh the device information and detect a file system (see section 5-2 "Using Devices" on page 69 for more information). L12-2(3) FSVol_Open() opens/mounts a volume. The parameters are the volume name (2a), the device name (2b) and the partition that will be opened (2c). There is no restriction on the volume name (2a); however, it is typical to give the volume the same name as the underlying device. If the default partition is to be opened, or if the device is not partition, then the partition number (2c) should be zero. If the SD/MMC initialization succeeds, the file system will produce the trace output as shown in Figure 12-10 (if a sufficiently high trace level is configured). See section E-9 "Trace Configuration" on page 507 about configuring the trace level. Figure 12-10 SD/MMC detection trace output 152 600-uC-FS-001.book Page 153 Wednesday, October 10, 2012 12:03 PM Using the SD/MMC SPI Driver 12-3-1 SD/MMC SPI COMMUNICATION SPI is a simple protocol supported by peripherals commonly built-in on CPUs. Moreover, since the communication can easily be accomplished by software control of GPIO pins ("software SPI" or "bit-banging"), a SD/MMC card can be connected to almost any platform. In SPI mode, seven pins on the SD/MMC device are used, with the functions listed in Table 12-4. As with any SPI device, four signals are used to communicate with the host (CS, DataIn, CLK and DataOut). Some card holders contain circuitry for card detect and write protect indicators, which the MCU/MPU may also monitor. Pin Name Type Description 1 CS I Chip Select 2 DataIn I Host-to-card commands and data 3 Vss1 S Supply voltage ground 4 VDD S Supply voltage 5 CLK I Clock 6 VSS2 S Supply voltage ground 7 DataOut O Card-to-host data and status Table 12-4 SD/MMC pinout (SPI mode) The four signals connecting the host (or master) and card (also known as the slave) are named variously in different manuals and documents. The DataIn pin of the card is also known as MOSI (Master Out Slave In); it is the data output of the host CPU. Similarly, the DataOut pin of the card is also known as MISO (Master In Slave Out); it is the data input of the host CPU. The CS and CLK pins (also known as SSEL and SCK) are the chip select and clock pins. The host selects the slave by asserting CS, potentially allowing it to choose a single peripheral among several that are sharing the bus (i.e., by sharing the CLK, MOSI and MISO signals). When a card is first connected to the host (at card power-on), it is in the `inactive' state, awaiting a GO_IDLE_STATE command to start the initialization process. The card will enter SPI mode (rather than card mode) because the driver holds the CS signal low while executing the GO_IDLE_STATE command. The card now in the `idle' state moves through the `ready' (as long as it supports the voltage range specified by the host) before ending up in `standby'. It can now get selected by the host (using the chip select) for data transfers. Figure 15-5 flowcharts this procedure. 153 600-uC-FS-001.book Page 154 Wednesday, October 10, 2012 12:03 PM Chapter 12 12-3-2 SD/MMC SPI COMMUNICATION DEBUGGING The SD/MMC SPI driver accesses the hardware through a port (SPI BSP) as described in section C-6 "SD/MMC SPI mode BSP" on page 452. A new BSP developed according to MCU/MPU documentation or by example must be verified step-by-step until flawless operation is achieved: 1 Initialization. Initialization must succeed. 2 Read data. Data must be read from card, in both single- and multiple-block transactions. 3 Write data. Data must be written to the card, in both single and multiple-block transactions, and subsequently verified (by reading the modified sectors and comparing to the intended contents). Start bit Transmission bit Command format 01 Cmd ix 6 bits End bit Argument 32 bits CRC 7 bits 1 CRC 7 bits 1 Start bit Transmission bit Response format 00 Cmd ix 6 bits End bit Response 32 or 128 bits (1) (2) Figure 12-11 SD/MMC SPI mode communication sequence F12-11(1) When no data is being transmitted, DataOut line is held high. F12-11(2) During busy signaling, DataOut line is held low. F12-11(3) The CRC is the 16-bit CCITT CRC. By default, this is optional and dummy bytes may be transmitted instead. The card only checks the CRC if CRC_ON_OFF has been executed. 154 600-uC-FS-001.book Page 155 Wednesday, October 10, 2012 12:03 PM Using the SD/MMC SPI Driver Start bit Transmission bit Command format 01 Cmd ix 6 bits End bit Argument 32 bits CRC 7 bits 1 Start bit Address Out Of Range/Block Length Error Address Misalign Erase Sequence Error Com CRC Error Illegal Command/Switch Error Erase Reset In Idle State Response format 0 Additional response (if any) R1 Response Figure 12-12 SD/MMC SPI mode command and response formats 155 600-uC-FS-001.book Page 156 Wednesday, October 10, 2012 12:03 PM Chapter 12 GO_IDLE_STATE Invalid command SEND_IF_COND Inactive state Power On (1) Valid command (2) SD_SEND_OP_COND SD_SEND_OP_COND (3) (3) SEND_OP_COND Idle State Invalid command READ_OCR (4) (5) READ_OCR No (5) V2.0+ Standard Capacity SD card V2.0+ High Capacity SD card SEND_CID (6) Ready State V1.x Standard Capacity SD card Yes SEND_CSD (7) Standby State MMC CCS in response? Figure 12-13 Simplified SD/MMC SPI mode initialization and state transitions The initialization process reveals that commands can be executed and proper responses are returned. The command responses in SPI mode are identical to those in cardmode (see Figure 12-5 and Figure 12-6), except each is preceded by a R1 status byte. Obvious errors, such as improper initialization or failed chip select manipulation, will typically be caught here. More subtle conditions may appear intermittently during reading or writing. 156 600-uC-FS-001.book Page 157 Wednesday, October 10, 2012 12:03 PM Using the SD/MMC SPI Driver 12-3-3 SD/MMC SPI BSP OVERVIEW An SPI BSP is required so that the SD/MMC SPI driver will work on a particular system. For more information about these functions, see section C-7 "SPI BSP" on page 453. Function Description FSDev_SD_SPI_BSP_SPI_Open() Open (initialize) SPI FSDev_SD_SPI_BSP_SPI_Close() Close (uninitialize) SPI FSDev_SD_SPI_BSP_SPI_Lock() Acquire SPI lock FSDev_SD_SPI_BSP_SPI_Unlock() Release SPI lock FSDev_SD_SPI_BSP_SPI_Rd() Read from SPI FSDev_SD_SPI_BSP_SPI_Wr() Write to SPI FSDev_SD_SPI_BSP_SPI_ChipSelEn() Enable chip select FSDev_SD_SPI_BSP_SPI_ChipSelDis() Disable chip select FSDev_SD_SPI_BSP_SPI_SetClkFreq() Set SPI clock frequency Table 12-5 SD/MMC SPI BSP functions 157 600-uC-FS-001.book Page 158 Wednesday, October 10, 2012 12:03 PM Chapter 12 158 600-uC-FS-001.book Page 159 Wednesday, October 10, 2012 12:03 PM Chapter 13 NAND Flash Driver Standard storage media (such as hard drives) and managed flash-based devices (such as SD/MMC and CF cards) require relatively simple drivers that convert the file system's request to read or write a sector into a hardware transaction. In comparison, the driver for a raw NAND flash is more complicated. Flash is divided into large blocks (often 16-kB to 512-kB); however, the high-level software (for example a FAT file system) expects to read or write small sectors (512-bytes to 4096-bytes) atomically. The driver implements a NAND block abstraction to conceal the device geometry from the file system. To aggravate matters, each block may be subjected to a finite number of erases. A wear-leveling algorithm must be employed so that each block is used equally. All these mechanisms are grouped in the main layer of the driver, called the NAND translation layer. The NAND flash driver included in C/FS has the following features: Dynamic wear-leveling: Using logical block addressing, the driver is able to change the physical location of written data on the NAND flash, so that a single memory location does not wear early while other locations are not used. Fail-safe to unexpected power-loss: The NAND flash driver was designed so that write transactions are atomic. After an unexpected power-down, the NAND flash's low-level format will still be consistent, the device will be remounted as if the transaction never occurred. Scalable: Various configuration options (see section 13-3-1 "Translation Layer Configuration" on page 171) are available for you to adjust the memory footprint; the speed and the wear-leveling performance of the driver. Flexible controller layer: You can provide your own implementation of the controller layer to take advantage of hardware peripherals and reduce CPU usage. However, a generic controller driver that is compatible with most parallel NAND flash devices and micro-controllers is provided. 159 600-uC-FS-001.book Page 160 Wednesday, October 10, 2012 12:03 PM Chapter 13 Error correction codes (ECC) management: Error correction codes are used to eliminate the bit read errors typical to NAND flash. It is easy to provide a software implementation of an ECC scheme or to interface to a hardware engine for each device used. It is then possible to configure the size of the codewords and the level of protection required to suit the needs of your application. Wide support for different NAND flashes: Most NAND flash memories are compatible with the driver, including large pages, small pages, SLC and MLC (single and multiple level cells) flash memory. Please contact Micrium to inquire about C/FS's compatibility with specific NAND devices. 13-1 GETTING STARTED The following section shows an example on how to get started in a typical case comprising the following: The generic controller layer implementation (included with the NAND driver) The 1-bit software ECC implementation (included with the NAND driver) The static part layer implementation (included with the NAND driver) Your BSP layer implementation to adapt the driver to your specific platform In case you need additional information and details regarding the different layers, please refer to the section 13-2 "Architecture Overview" on page 167. To use the NAND driver, you must include the following ten files in the build, in addition to the generic file system files: fs_dev_nand.c (\Micrium\Software\uC-FS\Dev\NAND.) fs_dev_nand.h (\Micrium\Software\uC-FS\Dev\NAND.) fs_dev_nand_ctrlr_gen.c (\Micrium\Software\uC-FS\Dev\NAND\Ctrlr) fs_dev_nand_ctrlr_gen.h (\Micrium\Software\uC-FS\Dev\NAND\Ctrlr) 160 600-uC-FS-001.book Page 161 Wednesday, October 10, 2012 12:03 PM Getting Started fs_dev_nand_part_static.c (\Micrium\Software\uC-FS\Dev\NAND\Part) fs_dev_nand_part_static.h (\Micrium\Software\uC-FS\Dev\NAND\Part) ecc_hamming.c (\Micrium\Software\uC-CRC\Source) ecc_hamming.h (\Micrium\Software\uC-CRC\Source) ecc.h (\Micrium\Software\uC-CRC\Source) Your BSP layer implementation (derived from fs_dev_nand_ctrlr_gen_bsp.c in \Micrium\Software\uC-FS\Dev\NAND\BSP\Template). The example in Listing 13-1 shows how to open a single NAND volume. The file system initialization function (FS_Init()) must have previously been called. #include #include #include #include #include #include #include #include <ecc_hamming.h> <fs.h> <fs_err.h> <fs_vol.h> <fs_dev_nand.h> <fs_dev_nand_ctrlr_gen.h> <fs_dev_nand_ctrlr_gen_soft_ecc.h> <fs_dev_nand_part_static.h> FS_NAND_FREE_SPARE_MAP static { CPU_BOOLEAN App_SpareMap[2] = { { 1, 63}, {-1, -1} }; App_FS_AddNAND (void) /* (1) */ FS_NAND_CFG cfg_nand = FS_NAND_DfltCfg; FS_NAND_CTRLR_GENERIC_CFG cfg_ctrlr = FS_NAND_CtrlrGen_DfltCfg; FS_NAND_CTRLR_GEN_SOFT_ECC_CFG cfg_soft_ecc = FS_NAND_CtrlrGen_SoftEcc_DfltCfg; FS_NAND_PART_STATIC_CFG cfg_part = FS_NAND_PartStatic_DfltCfg; FS_ERR err; FS_DevDrvAdd((FS_DEV_API *)&FS_NAND, /* (2) */ &err); if ((err != FS_ERR_NONE) && (err != FS_ERR_DEV_DRV_ALREADY_ADDED)) { APP_TRACE_DBG((" ...could not add driver w/err = %d\r\n\r\n", err)); return (DEF_FAIL); } 161 600-uC-FS-001.book Page 162 Wednesday, October 10, 2012 12:03 PM Chapter 13 /* (3) cfg_part.BlkCnt cfg_part.PgPerBlk */ = 2048; = 64; cfg_part.PgSize = 2048; cfg_part.SpareSize = 64; cfg_part.SupportsRndPgPgm = DEF_NO; cfg_part.NbrPgmPerPg cfg_part.BusWidth cfg_part.ECC_NbrCorrBits = 4; = 8; = 1; cfg_part.ECC_CodewordSize cfg_part.DefectMarkType cfg_part.MaxBadBlkCnt cfg_part.MaxBlkErase cfg_part.FreeSpareMap = = = = = 512 + 16; DEFECT_SPARE_L_1_PG_1_OR_N_ALL_0; 40; 100000; &spare_map[0]; /* (4) cfg_ctrlr.CtrlrExt = &FS_NAND_CtrlrGen_SoftECC; cfg_ctrlr.CtrlrExtCfg = &soft_ecc_cfg; */ /* (5) cfg_soft_ecc.ECC_ModulePtr = (ECC_CALC *)&Hamming_ECC; */ cfg_nand.BSPPtr cfg_nand.CtrlrPtr cfg_nand.CtrlrCfgPtr cfg_nand.PartPtr cfg_nand.PartCfgPtr cfg_nand.SecSize cfg_nand.BlkCnt = = = = = = = /* (6) */ (void *)&FS_NAND_BSP_SAM9M10; (FS_NAND_CTRLR_API *)&FS_NAND_CtrlrGeneric; &cfg_ctrlr; (FS_NAND_PART_API *)&FS_NAND_PartStatic; &cfg_part; 512; 2038u; cfg_nand.BlkIxFirst cfg_nand.UB_CntMax cfg_nand.RUB_MaxAssoc cfg_nand.AvailBlkTblEntryCntMax = = = = 10u; 10u; 2u; 10u; /* (7) */ FSDev_Open( "nand:0:", /* (a) */ (void *)&cfg_nand, /* (b) */ &err); switch (err) { case FS_ERR_NONE: APP_TRACE_DBG((" ...opened device.\r\n")); break; 162 600-uC-FS-001.book Page 163 Wednesday, October 10, 2012 12:03 PM Getting Started case FS_ERR_DEV_INVALID_LOW_FMT: case FS_ERR_DEV_INCOMPATIBLE_LOW_PARAMS: case FS_ERR_DEV_CORRUPT_LOW_FMT: APP_TRACE_DBG((" ...opened device (not low-level formatted).\r\n")); #if (FS_CFG_RD_ONLY_EN == DEF_ENABLED) FS_NAND_LowFmt("nand:0:", &err); /* (8) */ if (err != FS_ERR_NONE) { APP_TRACE_DBG((" ...low-level format failed.\r\n")); return 0; } #else APP_TRACE_DBG((" ...opening device failed w/err = %d.\r\n\r\n", err)); return 0; #endif break; case FS_ERR_DEV_ALREADY_OPEN: break; case FS_ERR_DEV: case FS_ERR_DEV_IO: case FS_ERR_DEV_TIMEOUT: case FS_ERR_DEV_NOT_PRESENT: default: APP_TRACE_DBG((" ...opening device failed w/err = %d.\r\n\r\n", err)); return (DEF_FAIL); } FSVol_Open("nand:0:", "nand:0:", 0, &err);*/ switch (err) { case FS_ERR_NONE: APP_TRACE_DBG((" break; /* (9) /* (a) /* (b) /* (c) */ */ */ */ ...opened volume (mounted).\r\n")); case FS_ERR_PARTITION_NOT_FOUND: /* Volume error. */ APP_TRACE_DBG((" ...opened device (not formatted).\r\n")); #if (FS_CFG_RD_ONLY_EN == DEF_DISABLED) FSVol_Fmt("nand:0:", (void *)0, &err); /* (10) */ if (err != FS_ERR_NONE) { APP_TRACE_DBG((" ...format failed.\r\n")); return (DEF_FAIL); } #else APP_TRACE_DBG((" ...opening device failed w/err = %d.\r\n\r\n", err)); return 0; #endif break; 163 600-uC-FS-001.book Page 164 Wednesday, October 10, 2012 12:03 PM Chapter 13 case FS_ERR_DEV: case FS_ERR_DEV_IO: case FS_ERR_DEV_TIMEOUT: /* Device error. */ case FS_ERR_DEV_NOT_PRESENT: APP_TRACE_DBG((" ...opened volume (unmounted).\r\n")); return (DEF_FAIL); default: APP_TRACE_DBG((" return (DEF_FAIL); ...opening volume failed w/err = %d.\r\n\r\n", err)); } return (DEF_OK); } Listing 13-1 Opening a NAND device volume L13-1(1) Declare and initialize configuration structures. Structures should be initialized to allow for forward compatibility in case some new fields in those structures are added in future C/FS versions. L13-1(2) Register the NAND device driver FS_NAND. L13-1(3) The NAND part layer configuration structure should be initialized. For more information about these parameters, see section "Statically configured part layer" on page 181. L13-1(4) The NAND controller layer configuration structure should be initialized. For more information about these parameters, see section 13-4-1 "Generic Controller Layer Implementation" on page 179. Please note that you might need to use a different controller layer. If this is the case, the configuration might be different (see section 13-4 "Controller Layer" on page 178). L13-1(5) The NAND generic controller software ECC extension should be initialized. For more information about these parameters, see section "Generic Controller Extension Layer" on page 180. Please note that if you are using a different controller layer implementation, there probably won't be a controller extension layer. Also, if using the generic controller, you might need to use a different extension. Refer to section "Generic Controller Extension Layer" on page 180 for a list of available controller extensions. 164 600-uC-FS-001.book Page 165 Wednesday, October 10, 2012 12:03 PM Getting Started L13-1(6) The NAND translation layer structure should be initialized. For more information about these parameters, see section 13-3-1 "Translation Layer Configuration" on page 171. L13-1(7) FSDev_Open() opens/initializes a file system device. The parameters are the device name (a) and a pointer to a device driver-specific configuration structure (b). The device name (a) is composed of a device driver name ("nand"), a single colon, an ASCII-formatted integer (the unit number) and another colon. L13-1(8) FS_NAND_LowFmt() low-level formats a NAND. If the NAND has never been used with C/FS, it must be low-level formatted before being used. Low-level formatting will create and initialize the low-level driver metadata on the device. L13-1(9) FSVol_Open() opens/mounts a volume. The parameters are the volume name (a), the device name (b) and the index of the partition that will be opened (c). There is no restriction on the volume name (a); however, it is typical to give the volume the same name as the underlying device. If the default partition is to be opened, or if the device is not partition, then the partition number (c) should be 0. L13-1(10) FSVol_Fmt() formats a file system device. If the NAND has just been low-level formatted, there will be no file system on the corresponding volume after it is opened (it will be unformatted). The volume must be formatted before files can be created or accessed. If the NAND initialization succeeds, the file system traces (if a sufficiently high trace level is configured) will produce an output similar to Listing 13-1. See section E-9 "Trace Configuration" on page 507 about configuring the trace level. 165 600-uC-FS-001.book Page 166 Wednesday, October 10, 2012 12:03 PM Chapter 13 =================================================================== = FS INITIALIZATION = =================================================================== Initializing FS... =========================================================== Adding/opening NAND volume "nand:0:"... NAND Ctrlr Gen: found NAND manuf id=2c, dev id=aa. FS_NAND_Open(): Using default blk cnt (all blocks): 2048. FS_NAND_Open(): Default number of entries in avail blk tbl. NAND FLASH FOUND: Name : Sec Size : Size : Update blks: FS_NAND_LowMountHandler(): Low ...opened device. "nand:0:" 2048 bytes 127360 sectors 10 level mount succeeded. FSPartition_RdEntry(): Found possible partition: Start: 0 sector Size : 0 sectors Type : 00 FS_FAT_VolOpen(): File system found: Type : FAT16 Sec size: 2048 B Clus size: 4 sec Vol size: 127360 sec # Clus : 31822 # FATs : 2 ...opened volume (mounted). ...init succeeded. =================================================================== =================================================================== Listing 13-2 NAND detection trace output HANDLING DIFFERENT USE-CASES If the above example does not apply to your situation, we strongly recommend you read the sections about the different layers. This will help you determine if other existing implementations are suitable for you, or if you need to develop your own implementation of some of those layers. 166 600-uC-FS-001.book Page 167 Wednesday, October 10, 2012 12:03 PM Architecture Overview 13-2 ARCHITECTURE OVERVIEW The NAND driver comprises multiple layers, as depicted in Figure 13-1. Interface with filesystem and/or application Part layer Obtain (in a static or dynamic manner) all parameters of the specific part/ chip. NAND Driver fs_dev_nand.* fs_dev_nand_cfg.h Provides generic driver interface (e.g., init, read, write) and performs wearleveling so all blocks are used equally. Controller layer fs_dev_nand_ctrlr_gen.* Implements particular controller/data bus and manages ECC correction. BSP fs_dev_nand_xxxx_bsp.c Access NAND device via bus interface or GPIO. Interface specific to controller layer implementation. Controller extension fs_dev_nand_ctrlr_gen_soft_ecc.* fs_dev_nand_ctrlr_gen_micron_ecc.* Manages ECC calculation and correction ECC Module ecc_hamming.* Software implementation of ECC calculation and correction. NAND Figure 13-1 NAND driver architecture The generic NAND translation layer provides sector abstraction and performs wear-leveling (to ensure all blocks are used equally). The controller layer driver interfaces with the NAND translation layer at the physical level (block erase, sector write/read, spare area write/read operations). The controller layer is also responsible for the placement of sectors and metadata within a NAND page. Interfacing at this level allows more flexibility: if your micro-controller has dedicated hardware like an ECC calculation engine or a NAND flash memory controller, you can interface directly with it by providing your own controller layer implementation instead of using the generic implementation (see section 13-4-1 "Generic Controller Layer Implementation" on page 179) included with the NAND driver. 167 600-uC-FS-001.book Page 168 Wednesday, October 10, 2012 12:03 PM Chapter 13 The controller extension layer is specific to the generic controller implementation (fs_dev_nand_ctrlr_gen.*). It provides an interface that allows different types of ECC calculation and correction schemes to be used while avoiding duplication of the generic controller code. Implementations for software ECC and some Micron on-chip ECC devices (including MT29F1G08ABADA) are provided with the NAND flash driver. The BSP layer will implement code that depends on your platform and application for the specific controller layer implementation chosen. In most cases, you will need to develop your own implementation of the BSP layer. The part layer is meant to provide the specifics for each part/chip you use in your design to the controller and NAND translation layers. This layer implementation will typically be chosen from the implementations included with the NAND driver. This implementation can either rely on statically defined parameters or values read directly from the device (for an ONFI compliant part). The ECC layer provides code calculation and error correction functions. For performance reasons, only a 1-bit ECC software module based on Hamming codes is provided (part of the C/CRC product bundled with C/FS). If a more robust ECC correction scheme is required, it is strongly recommended to use hardware engines. Since the ECC-specific code of the generic controller driver is implemented in generic controller extension modules, it can easily be adapted if the micro-controller or NAND flash device can handle ECC automatically. 13-3 NAND TRANSLATION LAYER The NAND translation layer is the main layer of the driver, implemented by the files fs_dev_nand.c and fs_dev_nand.h. This layer contains most of the algorithms necessary to overcome the following limitations of NAND flash technology: Write operations can only change a bit state from `1' to `0'. Only erase operations can revert the bit state, from `0' to `1'. Erase operations are only performed on large sections of the memory called blocks (typically between 16 kB and 512 kB). 168 600-uC-FS-001.book Page 169 Wednesday, October 10, 2012 12:03 PM NAND Translation Layer Write operations are performed on a sub-section of a block, called a page (typically between 512 and 8192 octets). Some devices support partial page programming (splitting the operation to write a full page into multiple operations that each write a sub-section of the page). Other devices can only have their pages written in a single operation before they are erased. Some devices must write the pages of a block in a sequential manner (page 0, page 1, page 2, etc.). Blocks can only be erased a limited number of times (typically 10k to 100k) before the integrity of the memory is compromised. Some device blocks can't be used reliably and are considered bad blocks. These blocks are either marked at the factory or become bad during the device's life. Electric disturbance can cause read errors. An error correction mechanism must be used to decrease the bit error rate. The role of the translation layer is to translate those NAND flash specific requirements into a disk interface, based on sector access. This disk interface allows the NAND driver to be used with traditional sector-based file systems like FAT, which is used by C/FS. The translation layer implementation provided with the NAND driver is inspired by the KAST (K-Associative Sector Translation) as proposed by Cho (see Appendix G, "Bibliography" on page 535). In the provided implementation, three types of blocks are present on the device. The data blocks typically occupy the major portion of the storage space. Data blocks are used to contain the data written to the device by the application or file system. A mapping between the logical addresses of the blocks and their physical locations is used to enable wear-leveling. This mapping, as well as other metadata, is contained in metadata blocks. Typically, only one block is used to store metadata. This block is also moved around for wear-leveling reasons. 169 600-uC-FS-001.book Page 170 Wednesday, October 10, 2012 12:03 PM Chapter 13 The third type of blocks are update blocks. All data written on the device must first be written through update blocks. Under specific circumstances (including an update block becoming full), the contents of an update block are folded onto data blocks. The folding operation roughly consists of three steps. The first step is to find an unused block and erase it. Secondly, the contents of the corresponding data block must be merged with the more recent, but incomplete data contained in the update block. This merged data is written in the recently-erased block. Once this operation is complete, metadata must be updated: the old data block and the update block are marked as free to erase and use, and the block mapping must be updated to point to the new data block. In this implementation, it is possible to specify how many different data blocks pointed to by a single update block. This specification is called maximum associativity (see the configuration field .RUB_MaxAssoc in section "Device configuration" on page 175). If this value is greater than one, the merge operation must be performed for each data block associated with the update block being folded. Each update block can be of one of the two sub-types: random update blocks (RUBs) and sequential update blocks (SUBs). Sequential update blocks can only refer to a single data block (associativity is always 1). Also, they must use the same exact layout as a data block (i.e. logical sector 0 written at physical sector 0, logical sector 1 written at physical sector 1, etc.). The advantage of SUBs is that they have a much lower merge cost. They can be converted into data blocks in-place by copying missing sectors from the associated data block and updating some metadata. Random update blocks, on the other hand, can contain sectors from multiple data blocks. Those sectors can be written at any location in the RUB since it contains additional metadata to map each sector to an appropriate location in a data block, resulting in an increased merge cost but allowing for better wear-leveling since it leads to better block usage in the case of random writes. Another important functionality of the translation layer is to keep track of the number of erase operations performed on each block. The erase count is critical for two reasons. First, the erase count can be used to efficiently drive the wear-leveling algorithm, allowing seldom erased blocks to be preferred over frequently erased blocks, when a new block is required. Secondly, the erase count allows the translation layer to detect the blocks that have reached their erase limit. 170 600-uC-FS-001.book Page 171 Wednesday, October 10, 2012 12:03 PM NAND Translation Layer Since the erase count information is stored in each block, each erase count must be backed-up somewhere else in the device prior to erasing a block. Blocks that have their erase count backed-up are called available blocks. When the translation layer needs a new block, it will always be taken from the available blocks table to make sure its erase count is not lost in the case of an unexpected power-down. All this functionality is embedded within the translation layer. Using the software itself does not require a deep understanding of the mechanisms as they are all abstracted into a simpler, easier to understand disk interface. However, understanding the internals can be useful to efficiently configure the translation layer. 13-3-1 TRANSLATION LAYER CONFIGURATION The configuration of the NAND translation layer (fs_dev_nand.*) must be done through two mechanisms. First, you need to specify driver-wide configuration options in the configuration file (fs_dev_nand_cfg.h). Then, you need to configure the device-specific options passed to the function FSDev_Open() through a structure pointer. You need to call FSDev_Open() for each device you want to access and provide a proper device-specific configuration for each of them. DRIVER CONFIGURATION FILE The driver configuration file for the NAND translation layer is fs_dev_nand_cfg.h. A template for this file is located in the following path: \Micrium\Software\uC-FS\Dev\NAND\Cfg\Template\ The driver configuration #defines available in the configuration file are listed below. FS_NAND_CFG_AUTO_SYNC_EN This #define determines if, for each operation on the device (i.e. each call to the device's API), the metadata should be synchronized. Synchronizing at the end of each operation is safer; it ensures the device can be remounted and appear exactly as it should. Disabling automatic synchronization can result in a large write speed increase, as the metadata won't be committed automatically, unless triggered by the application. If a power down occurs between a device operation and a sync operation, the device will appear as it was in a prior state when remounted. Device synchronization can be forced with a call to FSDev_Sync(). 171 600-uC-FS-001.book Page 172 Wednesday, October 10, 2012 12:03 PM Chapter 13 Note that using large write buffers will reduce the metadata synchronization performance hit, as fewer calls to the device API will be needed. FS_NAND_CFG_UPDATE_BLK_META_CACHE_EN This #define determines if, for each update block, the metadata will be cached. Enabling this will allow searching for a specific updated sector through data in RAM instead of accessing the device, which would require additional read page operations. More RAM will be consumed if this option is enabled, but write/read speed will be improved. RAM usage = <Nbr update blks> x (log2(<Max associativity>) + log2(<Nbr secs per blk>)) / 8 octets. The result should be rounded up. FS_NAND_CFG_DIRTY_MAP_CACHE_EN This #define determines if the dirty blocks map will be cached. With this feature enabled, a copy of the dirty blocks map on the device is cached. It is possible then to determine if the state "dirty" of a block is committed on the device without the need to actually read the device. With this feature enabled, overall write and read speed should be improved. Also, robustness will be improved for specific cases. However, more RAM will be consumed. RAM usage = <Nbr of blks on device> / 8 octets The result should be rounded up. FS_NAND_CFG_UPDATE_BLK_TBL_SUBSET_SIZE This #define controls the size of the subsets of sectors pointed by each entry of the update block tables. The value must be a power of 2 (or 0). If, for example, the value is 4, each time a specific updated sector is requested, the NAND translation layer must search the sector in a group of four sectors. Thus, if the update block metadata cache (FS_NAND_CFG_UPDATE_BLK_META_CACHE_EN) is disabled, four sectors must be read from the device to find the requested sector. The four entries will instead be read 172 600-uC-FS-001.book Page 173 Wednesday, October 10, 2012 12:03 PM NAND Translation Layer from the cache, if it is enabled. If the value is set to 0, the table will be disabled completely, meaning that all sectors of the block might have to be read before the specified sector is found. If the value is 1, the table completely specifies the location of the sector, and thus no search must be performed. In that case, enabling the update block metadata cache will yield no performance benefit. RAM usage = <Nbr update blks> x (log2(Nbr secs per blk>) - log2(<Subset size>) x <Max associativity> / 8 octets The result should be rounded up. FS_NAND_CFG_RSVD_AVAIL_BLK_CNT This #define indicates the number of blocks in the available blocks table that are reserved for metadata block folding. Since this operation is critical and must be done before adding blocks to the available blocks table, the driver needs enough reserved blocks to make sure at least one of them is not bad so that the metadata can be folded successfully. When set to 3, probability of the metadata folding operation failing is almost null. This value is sufficient for most applications. FS_NAND_CFG_MAX_RD_RETRIES This #define indicates the maximum number of retries performed when a read operation fails. It is recommended by most manufacturers to retry reading a page if it fails, as successive read operations might be successful. This number should be at least set to 2 for smooth operation, but might be set higher to improve reliability. Please be aware that a high number of retries will reduce the response time of the system when it tries to read a defective sector. FS_NAND_CFG_MAX_SUB_PCT This #define indicates the maximum allowed number of sequential update blocks (SUB). This value is set as a percentage of the total number of update blocks. SUBs will improve the performance for large transactions on the file system (ex: copying multi-MB files). Small files or small iterative changes to large files are best handled by RUBs. It is important to note that the translation layer will automatically determine what type of update block is the best depending on the parameters of the transaction itself. This parameter is only to limit the number of update blocks that can be SUBs. 173 600-uC-FS-001.book Page 174 Wednesday, October 10, 2012 12:03 PM Chapter 13 ADVANCED CONFIGURATION OPTIONS The following configuration #defines should be left at their default values. Advanced understanding of the wear-leveling and block abstraction algorithms is necessary to set these configurations. FS_NAND_CFG_TH_PCT_MERGE_RUB_START_SUB This #define indicates the minimum size (in sectors) of the write operation needed to create a sequential update block (SUB) when a random update block (RUB) already exists. SUBs offer a substantial gain in merge speed when a large quantity of sectors are written sequentially (within a single or multiple write operations). However, if many SUBs are created and merged early, the device will wear faster (less sectors written between block erase operations). This threshold is set as a percentage (relative to the number of sectors per block). Set higher than default for better overall wear leveling and lower than default for better overall write speed. FS_NAND_CFG_TH_PCT_CONVERT_SUB_TO_RUB This #define indicates the minimum size (in sectors) of free space needed in a sequential update block (SUB) to convert it to a random update block (RUB). RUBs have more flexible write rules, at the expense of a longer merge time. If the SUB's usage is over the threshold, the SUB will be merged and a new RUB will be started, instead of performing the conversion from SUB to RUB. This threshold is set as a percentage (relative to number of sectors per block). Set higher than default for better overall write speed and lower than default for better overall wear leveling. To take advantage of this threshold, it must be set higher than the value of FS_NAND_CFG_TH_PCT_PAD_SUB. Otherwise, this threshold won't have any effect. 174 600-uC-FS-001.book Page 175 Wednesday, October 10, 2012 12:03 PM NAND Translation Layer FS_NAND_CFG_TH_PCT_PAD_SUB This #define indicates the maximum size (in sectors) that can be skipped in a sequential update block (SUB). Since each sector of a SUB must be written at a single location (sector physical index == sector logical index), it is possible to allow small gaps in the sequence. Larger gaps are more flexible, and can improve the overall merge speed, at the cost of faster wear, since some sectors are left empty between erase operations. This threshold is set as a percentage (relative to number of sectors per block). Set higher than default for better overall write speed and lower than default for better overall wear leveling FS_NAND_CFG_TH_PCT_MERGE_SUB This #define indicates the maximum size (in sectors) of free space needed in a sequential update block (SUB) to merge it to allocate another update block. If the threshold is exceeded, a random update block (RUB) will be merged instead. This threshold must be set so that SUBs with a lot of free space are not merged. Merging SUBs early will generate additional wear. This threshold is set as a percentage (relative to number of sectors per block). FS_NAND_CFG_TH_SUB_MIN_IDLE_TO_FOLD This #define indicates the minimum idle time (specified as the number of driver accesses since the last access that has written to the SUB) for a sequential update block (SUB) to be converted to a random update block (RUB). This threshold must be set so that "hot" SUBs are not converted to RUBs. DEVICE CONFIGURATION You must configure the NAND translation layer for each device you use in your project. This configuration is made through a structure of type FS_NAND_CFG. A pointer to this structure is then passed to the function FSDev_Open(). Each NAND device will need to be initialized by calling FSDev_Open() and passing it a unique structure pointer of the type FS_NAND_CFG. Note that the FS_NAND_DfltCfg constant should be used to initialize the FS_NAND_CFG structure to default values. This will ensure all fields will automatically be set to sane default values. 175 600-uC-FS-001.book Page 176 Wednesday, October 10, 2012 12:03 PM Chapter 13 typedef struct void fs_nand_cfg { *BSPPtr; (1) FS_NAND_CTRLR_API void FS_NAND_PART_API *CtrlrPtr; *CtrlrCfgPtr; *PartPtr; (2) (3) (4) void FS_SEC_SIZE FS_NAND_BLK_QTY *PartCfgPtr; SecSize; BlkCnt; (5) (6) (7) FS_NAND_BLK_QTY FS_NAND_UB_QTY CPU_INT08U CPU_INT08U } FS_NAND_CFG; BlkIxFirst; UB_CntMax; RUB_MaxAssoc; AvailBlkTblEntryCntMax; (8) (9) (10) (11) Listing 13-3 NAND translation layer configuration structure L13-3(1) This field must be set to a pointer to the controller-specific BSP layer implementation's API you want the controller layer to use (see section 13-5 "Board Support Package - Generic Controller" on page 185). If you use a different controller layer implementation, that field might not be needed. L13-3(2) This field must be set to a pointer to the controller layer implementation's API you wish to use (see section 13-4 "Controller Layer" on page 178). L13-3(3) This field must be set to a pointer to the configuration structure for the specified controller layer implementation. L13-3(4) This field must be set to a pointer to the part layer implementation's API you wish to use (see section Listing 13-10 "API structure type for generic controller extension" on page 191) L13-3(5) This field must be set to a pointer to the configuration structure specific to the chosen part layer implementation. L13-3(6) This field must contain the sector size for the device (care must be taken when choosing sector size: see section 13-7 "Performance Considerations" on page 187). The value FS_NAND_CFG_DEFAULT instructs the translation layer to use the page size reported by the part layer as its sector size. 176 600-uC-FS-001.book Page 177 Wednesday, October 10, 2012 12:03 PM NAND Translation Layer L13-3(7) This field must contain the number of blocks you want C/FS to use. This can be useful if you want to reserve blocks for data to be used outside the file system (by a bootloader, for example). The value FS_NAND_CFG_DEFAULT instructs the translation layer to use the number of blocks reported by the part layer. L13-3(8) This field must contain the index of the first block you want C/FS to use. This can be useful if you want to reserve blocks for data to be used outside the file system (by a bootloader, for example). L13-3(9) This field must be set to the maximum number of update blocks you want the NAND translation layer to use. A greater number can improve performance but will also reduce available space on the device and consume RAM. You are encouraged to experiment with different values to evaluate which one suits your application best. L13-3(10) This field must be set to the maximum associativity of the random update blocks (RUB). The update blocks temporarily contain sectors from data blocks until they are merged (copied to respective data blocks). The associativity specifies the number of data blocks from which a single RUB can contain sectors. A high setting will usually lead to better overall write and read speeds and will reduce wear. However, a low setting will lower the time of execution of the worst-case write operation. L13-3(11) This field must be set to the size of the available blocks table. Available blocks are ready to be erased and used as update or data blocks. The table must, at least, be large enough to contain the reserved available blocks (see section "FS_NAND_CFG_RSVD_AVAIL_BLK_CNT" on page 173) and a few more for general operations. The value FS_NAND_CFG_DEFAULT instructs the translation layer to use 10 or (1 + FS_NAND_CFG_RSVD_AVAIL_BLK_CNT) entries, whichever is larger. 177 600-uC-FS-001.book Page 178 Wednesday, October 10, 2012 12:03 PM Chapter 13 13-3-2 TRANSLATION LAYER SOURCE FILES The files relevant to the NAND translation layer are outlined in this section; the generic file-system files, outlined in Chapter 3, "C/FS Directories and Files" on page 29, are also required. \Micrium\Software\uC-FS\Dev\NAND This directory contains the NAND driver files. \fs_dev_nand.* These files compose the NAND translation layer. These following source files contain the code for the NAND translation layer. \Cfg\Template\fs_dev_nand_cfg.h This is a template file that is required to be copied to the application directory to configure the C/FS NAND driver based on application requirements. 13-4 CONTROLLER LAYER The controller-layer implementations distributed with the NAND driver (see Table 13-1) support a wide variety of flash devices from major vendors. Driver API Files Description FS_NAND_CtrlrGen fs_dev_nand_ctrlr_gen.* in Supports most parallel flash devices interfaced on an MCU's /Micrium/Software/uC-FS/Dev/NA ND/Ctrlr external memory bus. Table 13-1 Controller-layer implementations provided Of course, it is possible that your specific device and/or micro-controller requires a different controller layer implementation, or that a different implementation could take advantage of hardware modules (like a memory controller on a MCU). Please refer to the section 13-8-4 "Controller Layer Development Guide" on page 194 for the details on how to implement your own controller layer. 178 600-uC-FS-001.book Page 179 Wednesday, October 10, 2012 12:03 PM Controller Layer 13-4-1 GENERIC CONTROLLER LAYER IMPLEMENTATION The generic controller layer driver is an implementation of the controller layer that is compatible with most parallel NAND devices and most simple memory controllers. It has the following features: Supports multiple sector per page Packs out-of-sector (OOS) metadata around reserved spare area zones Extensible through extensions that provides multiple hooks to allow for different ECC protection schemes (an extension for software ECC is provided) Supports reading ONFI parameter pages through a its IO_Ctrl() function Supports both 8-bit and 16-bit bus devices The generic controller driver imposes a specific page layout: the sectors are stored sequentially in the main page area and OOS metadata zones are stored sequentially in the spare area, packed in the free spare zones specified by the .FreeSpareMap field of the associated FS_PART_DATA data structure. An example layout is shown below for a device with 2048 octets pages, using 512 bytes sectors. 20 4 20 8 49 20 2058 62 20 2071 75 20 2084 88 20 2197 01 15 36 10 24 51 2 0 Free ECC 4 ECC 3 OOS 4 ECC 2 OOS 3 ECC 1 Sector 4 OOS 2 Sector 3 OOS 1 Sector 2 Reserved Sector 1 Figure 13-2 Example generic controller driver page layout To determine if the generic controller driver is compatible with your hardware, you can study its BSP interface, described in section 13-8-1 "BSP Development Guide - Generic Controller" on page 189. 179 600-uC-FS-001.book Page 180 Wednesday, October 10, 2012 12:03 PM Chapter 13 GENERIC CONTROLLER EXTENSION LAYER The generic controller extension layer extends the functionality of the generic controller, mostly with regards to ECC. It allows for the reuse of the generic controller code, enabling easy customizations of the controller layer. The NAND driver ships with two generic controller extensions: Extension API Files Description FS_NAND_CtrlrGen_SoftECC fs_dev_nand_ctrlr_gen_soft_ecc.* in Supports software ECC calculation and correction through /Micrium/Software/uC-FS/Dev/NAN D/Ctrlr C/CRC ECC modules. fs_dev_nand_ctrlr_gen_micron_ecc.* in Supports on-chip ECC hardware for some Micron parts (ex: /Micrium/Software/uC-FS/Dev/NAN D/Ctrlr MT29F01G08ABADA). FS_NAND_CtrlrGen_MicronECC Table 13-2 Generic controller layer extensions provided The software ECC generic controller extension (FS_NAND_CtrlrGen_SoftECC) uses C/CRC's ECC modules for the ECC codewords calculation and data correction. The extension is configurable through a FS_NAND_CTRLR_GEN_SOFT_ECC_CFG type structure. It should be initialized to the value FS_NAND_CtrlrGen_SoftEcc_DfltCfg before its fields are overridden to the appropriate values for your application. typedef struct fs_nand_cfg { const ECC_CALC *ECC_ModulePtr; } FS_NAND_CFG; (1) Listing 13-4 NAND translation layer configuration structure L13-4(1) 180 Pointer to an ECC_CALC API structure that will be used to provide software ECC calculation and correction. Refer to section 13-8-3 "ECC Module Development Guide" on page 193 and C/CRC's user manual for more information on ECC modules. 600-uC-FS-001.book Page 181 Wednesday, October 10, 2012 12:03 PM Controller Layer The Micron ECC generic controller extension (FS_NAND_CtrlrGen_MicronECC) allows the use of internal on-chip hardware ECC engines for some Micron NAND flash parts. The extension has been designed as an example for the Micron MT29F1G08ABADA, but should function properly with other similar Micron devices with internal ECC hardware modules. This module doesn't have any configuration options, you should use DEF_NULL as the generic controller extension configuration pointer (.CtrlrExtCfg field of the FS_NAND_CTRLR_GEN_CFG structure). 13-4-2 PART LAYER There are two different part-layer implementations distributed with the NAND driver (see Table 13-3). Driver API Files Description FS_NAND_PartStatic fs_dev_nand_part_static.* Manually configure the in /Micrium/Software/uC-FS/Dev/NA parameters of each NAND flash device you use. ND/Part FS_NAND_PartONFI fs_dev_nand_part_onfi.* in Use the parameters automatically obtained by reading the /Micrium/Software/uC-FS/Dev/NA ND/Part parameter page of ONFI-compliant NAND flash devices. Table 13-3 Part-layer implementations provided It is mandatory to use one part-layer implementation for the NAND driver to work. It is recommended to use one of the provided implementations. STATICALLY CONFIGURED PART LAYER This part-layer implementation is the basic one. It lets you set all the physical characteristics of the device through a configuration structure of type FS_NAND_PART_STATIC_CFG. Typically, the pointer to the configuration structure is then assigned to the field .PartCfgPtr of the translation layer configuration structure (see section 13-3 "NAND Translation Layer" on page 168). The pointer to the translation layer configuration structure can then be passed as an argument to the function FSDev_Open(). Refer to section 13-1 "Getting Started" on page 160 for an example of configuration. The part configuration 181 600-uC-FS-001.book Page 182 Wednesday, October 10, 2012 12:03 PM Chapter 13 structure should be initialized to FS_NAND_PartStatic_DfltCfg to ensure upward compatibility with future versions. The configuration fields available for the static part layer are described in Listing 13-5: typedef struct fs_nand_part_static_cfg { FS_NAND_BLK_QTY FS_NAND_PG_PER_BLK_QTY FS_NAND_PG_SIZE FS_NAND_PG_SIZE CPU_INT08U CPU_INT08U CPU_INT08U FS_NAND_PG_SIZE FS_NAND_DEFECT_MARK_TYPE FS_NAND_BLK_QTY CPU_INT32U FS_NAND_FREE_SPARE_DATA } FS_NAND_PART_STATIC_CFG; BlkCnt; PgPerBlk; PgSize; SpareSize; NbrPgmPerPg; BusWidth; ECC_NbrCorrBits; ECC_CodewordSize; DefectMarkType; MaxBadBlkCnt; MaxBlkErase; *FreeSpareMap; (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) Listing 13-5 NAND static part layer configuration structure L13-5(1) Number of blocks in your device. L13-5(2) Number of pages per block in your device. L13-5(3) Page size (in octets) of your device. L13-5(4) Size of the spare area (in octets) of your device. L13-5(5) Number of partial page programming allowed before an erase operation (for example, it would be set to 4 if a device with 2048 octets pages could be written in 4 accesses of 512 octets). L13-5(6) Number of input/output lines of the device's bus. L13-5(7) Minimum required number of correctable bits per codeword for the ECC. L13-5(8) Codeword size required for ECC. The codeword size corresponds to the maximum data size (in octets) that must be sent to the ECC calculation module to get a single error correction code. 182 600-uC-FS-001.book Page 183 Wednesday, October 10, 2012 12:03 PM Controller Layer L13-5(9) Factory defect mark type. This determines how the translation layer can detect if a block factory is marked as a defect block. The possible values are listed below. Unless otherwise specified, any unset bit in the defect mark indicates a defective block. A byte refers to an 8-bit value, a word refers to a 16-bit value and a location is a bus width wide value (byte for 8-bit bus and word for 16-bit bus). DEFECT_SPARE_L_1_PG_1_OR_N_ALL_0: the defect mark is in the first location of the spare area (first byte or first word, depending on bus width) of the first or last page. If the mark reads 0, the block is defective. DEFECT_SPARE_ANY_PG_1_OR_N_ALL_0: any location in the spare area or the first or last page equal to 0 indicates a defective block. DEFECT_SPARE_B_6_W_1_PG_1_OR_2: the defect mark is the sixth byte or the first word of the spare area (depending on bus width) of the first or second page. DEFECT_SPARE_L_1_PG_1_OR_2: the defect mark is the first location in the spare area of the first or second page. DEFECT_SPARE_B_1_6_W_1_IN_PG_1: the defect mark is the first and sixth byte or the first word of the spare area (depending on bus width) of the first page. DEFECT_PG_L_1_OR_N_PG_1_OR_2: the defect mark is the first or last location of the page area in the first or second page. L13-5(10) Maximum number of bad blocks within a single device during its lifetime. L13-5(11) Maximum number of erase operations that can be performed on a single block. L13-5(12) Pointer to the map of the free regions in the spare area (see Listing 13-6). Listing 13-6 shows the data type used to specify the contiguous regions of the spare area that are available for the NAND driver to write. The map of the free regions is an array of FS_NAND_FREE_SPARE_DATA values. Each free contiguous section of the spare area will use one index of the array. There must also be a last entry set to {-1, -1} for the driver to 183 600-uC-FS-001.book Page 184 Wednesday, October 10, 2012 12:03 PM Chapter 13 know when to stop parsing the table. Note that the factory defect mark should be excluded of the free regions. You can also refer to the example (see section 13-1 "Getting Started" on page 160). typedef struct fs_nand_free_spare_data { FS_NAND_PG_SIZE OctetOffset; (1) FS_NAND_PG_SIZE OctetLen; } FS_NAND_FREE_SPARE_DATA; (2) Listing 13-6 NAND configuration structure for free regions of the spare area L13-6(1) Offset (in octets) of a free region. L13-6(2) Length (in octets) of a free region. ONFI PART LAYER The ONFI part layer implementation is able to obtain from ONFI compliant devices all the parameters necessary for the NAND driver to operate. The different parameters are extracted from the device parameter page. Table 13-4 lists the versions of the ONFI standard for which automatic parameter page parsing is supported. If your device does not respect this standard, it should be used with a different implementation o f the part layer. ONFI version Supported parameter page ONFI 3.0 YES ONFI 2.3a YES ONFI 2.2 YES ONFI 2.1 YES ONFI 2.0 YES ONFI 1.0 YES Table 13-4 ONFI parameter page support for different ONFI versions 184 600-uC-FS-001.book Page 185 Wednesday, October 10, 2012 12:03 PM Board Support Package - Generic Controller The ONFI part layer implementation does not have a lot of configuration options since most parameters are read from the device's parameter page. The part configuration structure should be initialized to FS_NAND_PartONFI_DfltCfg to ensure upward compatibility with future versions. The configuration fields available for the ONFI part layer implementation are described in Listing 13-7: typedef struct fs_nand_part_onfi_cfg { FS_NAND_FREE_SPARE_DATA *FreeSpareMap; } FS_NAND_PART_ONFI_CFG; (1) Listing 13-7 NAND ONFI part layer configuration structure L13-7(1) Pointer to the map of the free regions in the spare area (see Listing 13-6). 13-5 BOARD SUPPORT PACKAGE - GENERIC CONTROLLER If you use the generic controller layer implementation, you will have to provide a board support package to interface with your board layout and hardware. The board support package must be provided in the form of an API pointer of the type FS_NAND_CTRLR_GEN_BSP_API, like shown in Listing 13-8: 185 600-uC-FS-001.book Page 186 Wednesday, October 10, 2012 12:03 PM Chapter 13 typedef struct fs_nand_ctrlr_gen_bsp_api { void (*Open) (FS_ERR *p_err); void (*Close) (void); void void void void (*ChipSelEn) (*ChipSelDis) (*CmdWr) (void); (void); (CPU_INT08U *p_cmd, (*AddrWr) CPU_SIZE_T FS_ERR (CPU_INT08U cnt, *p_err); *p_addr, cnt, *p_err); *p_src, cnt, *p_err); *p_dest, cnt, *p_err); *poll_fcnt_arg, void (*DataWr) void (*DataRd) CPU_SIZE_T FS_ERR (void CPU_SIZE_T FS_ERR (void (*WaitWhileBusy) CPU_SIZE_T FS_ERR (void void CPU_BOOLEAN CPU_INT32U FS_ERR (*poll_fcnt)(void to_us, *p_err); *arg), } FS_NAND_CTRLR_GEN_BSP_API; Listing 13-8 BSP API type for the generic controller layer implementation Typically, you will provide the board support package implementation. See section 13-8-1 "BSP Development Guide - Generic Controller" on page 189 for details on how to implement the BSP layer. 13-6 BOARD SUPPORT PACKAGE - OTHER CONTROLLERS If you use a different controller layer implementation than the generic, you will typically need a BSP layer implementation identical or mostly similar. Please refer to section 13-5 "Board Support Package - Generic Controller" on page 185 unless there is a section of this chapter dedicated to your BSP. 186 600-uC-FS-001.book Page 187 Wednesday, October 10, 2012 12:03 PM Performance Considerations 13-7 PERFORMANCE CONSIDERATIONS Several performance aspects can be considered when using the NAND driver. Depending on your priorities, you will need to configure and use the NAND driver in a proper way so that your specific goals are met. The different performance metrics include the write and read/speed, the RAM usage, the data safety level and the worst-case locking time. CHOOSING AN APPROPRIATE SECTOR SIZE It is important to choose carefully the sector size for each device. Unless your device supports partial page programming, it is mandatory for the sector size to be identical to the page size or larger. If your device supports partial page programming, it is possible for you to set a sector size smaller than the page size as long as it does not force the driver to exceed the maximum number of partial page programs. If this is not respected, the driver will fail the initialization phase and return an error code. One of the advantages of choosing a sector size smaller than the page size is to reduce the RAM usage. The size of the buffers in the file system are based on the sector size. A large sector size implies large buffers. For the best performance, the sector size should be in the ballpark of a typical transaction. If most of your write operations are a couple of octets, you should, if possible, choose a small sector size (typically 512 octets). On the other hand, if you want to obtain good transfer rates and you have large application buffers (with multimedia applications, for example), then the sector size should be set higher. The optimal choice will almost always be the same as the page size (512, 2048, 4096 octets). CHOOSING ERROR CORRECTION CODES Each device needs an error correction codes (ECC) module able to correct a minimal number of bits per codeword. Choosing a module that satisfies the minimum required level of error correction is often the best option if you want to avoid the extra calculation time of modules with enhanced bit error correction. 187 600-uC-FS-001.book Page 188 Wednesday, October 10, 2012 12:03 PM Chapter 13 To reduce the calculation load on your CPU, it is recommended to consider using a hardware ECC module. This is especially true with parts that require more than 1 bit per codeword of error correction. These hardware ECC engines are often found in MCU and in NAND flash devices. Consult their datasheets to determine if you have access to such a feature. If data safety is a concern, you can consider using an ECC module with better correction capacity. For most applications, the recommended level of correction is sufficient. However, using an ECC engine that can correct more bit-errors can improve long-term readability of the data, especially for cold data (that never or rarely changes). Another option is to reduce the codeword size. The same number of bit errors can be corrected, but since codewords are smaller, the bit error rate will be smaller. While those design choices will slightly improve reliability, they will also increase the overhead and hence reduce the read/write speed and increase the worst-case locking time. CONFIGURE THE TRANSLATION LAYER The configuration of the translation layer is complicated. Take the time needed to read carefully each description, and make sure you choose a configuration that is appropriate for your application. When, in most cases, the basic configuration will be enough, optimizing it will help you to reach your goals, whether they are about CPU usage, footprints, reliability or speed. The translation layer configuration options are described in section 13-3-1 "Translation Layer Configuration" on page 171. CONSIDERING ANOTHER CONTROLLER LAYER Some MCUs have advanced peripherals that interface with NAND flash devices. If this is the case, consider using or developing a specialized controller layer implementation to take advantage of those peripherals and save some CPU time or increase performances. 13-8 DEVELOPMENT GUIDE This section describes the code you might need to implement to adapt the driver to your specific hardware and application. Typically, you will only need to implement the BSP layer for an available controller layer implementation. In other cases, you might need to provide an implementation for the ECC module and/or the controller layer. 188 600-uC-FS-001.book Page 189 Wednesday, October 10, 2012 12:03 PM Development Guide 13-8-1 BSP DEVELOPMENT GUIDE - GENERIC CONTROLLER If you use the generic controller layer implementation, a BSP is required so that it will work for a particular board, micro-controller or application. Other controller layer implementations might require a similar BSP layer. The BSP must declare an instance of the BSP API type (FS_NAND_CTRLR_GEN_BSP_API) as a global variable within the source code. The API structure is an ordered list of function pointers used by the generic controller layer implementation. The BSP API type is shown in Listing 13-8. An example of a BSP API structure definition is shown in Listing 13-9: const FS_NAND_CTRLR_GEN_BSP_API FS_NAND_BSP_Open, FS_NAND_BSP_Close, FS_NAND_BSP_ChipSelEn, FS_NAND_BSP_ChipSelDis, FS_NAND_BSP_CmdWr, FS_NAND_BSP_AddrWr, FS_NAND_BSP_DataWr, FS_NAND_BSP_DataRd, FS_NAND_BSP_WaitWhileBusy }; FS_NAND_BSP_SAM9M10 = { (1) (2) (3) (4) (5) (6) (7) (8) (9) Listing 13-9 Example BSP API structure for generic controller A proper BSP should implement all of these functions. OPEN/CLOSE FUNCTIONS The Open() and Close() functions will be called respectively by FSDev_Open() and FSDev_Close(). Typically, FSDev_Open() is called during initialization and FSDev_Close() is never called -- closing a fixed device doesn't make much sense. When implementing the Open() function of the BSP layer, you should add all necessary code for the hardware initialization. That might include setting up the memory controller general settings and timings for the bank associated with the NAND device, configuring the chip select and ready/busy through either the memory controller or GPIO, configuring the memory controller clock, configuring the memory controller I/O pins, etc. The Close() function is typically left empty. 189 600-uC-FS-001.book Page 190 Wednesday, October 10, 2012 12:03 PM Chapter 13 CHIP SELECTION FUNCTIONS The ChipSelEn() and ChipSelDis() are called (in pairs) each time the device must be accessed. In these functions, you should implement any chip selection mechanism needed. If the bus and/or hardware is shared with more than one task, the chip selection functions should also implement proper locking. If the shared bus and/or hardware must be configured differently when used outside the NAND driver, the configuration changes must be done within the ChipSelEn() and ChipSelDis() functions. COMMAND WRITE FUNCTION The CmdWr() function must write cnt octets on the bus with the CLE (Command Latch Enable) pin asserted. ADDRESS WRITE FUNCTION The AddrWr() function must write cnt octets on the bus with the ALE (Address Latch Enable) pin asserted. DATA WRITE FUNCTION The DataWr() function must write cnt octets on the bus with both ALE and CLE not asserted. DATA READ FUNCTION The DataRd() function must read cnt octets from the bus and store it, starting from the p_src address. The ALE and CLE signals must not be asserted. WAIT WHILE BUSY FUNCTION This function should block until the ready pin of the NAND device is in the appropriate state. If for any reason this pin is not accessible, you should call the poll_fcnt() with the poll_fcnt_arg as argument. This poll function will verify if the NAND device is ready by polling the NAND device status instead. Once the poll function returns DEF_YES, the WaitWhileBusy() can return without setting an error code. If the time out limit is reached, the function should return with an error code set to FS_ERR_DEV_TIMEOUT. 190 600-uC-FS-001.book Page 191 Wednesday, October 10, 2012 12:03 PM Development Guide 13-8-2 GENERIC CONTROLLER EXTENSION DEVELOPMENT GUIDE The generic controller extension layer allows extending the generic controller through a number of hook functions that are used by the generic controller, when flexibility in handling a specific operation is desirable. A generic controller extension is defined through a structure of type FS_NAND_CTRLR_GEN_EXT, described in Listing 13-10. Note that all unused function pointers should be set to DEF_NULL. typedef struct void fs_nand_ctrlr_gen_ext { (*Init) (FS_ERR void *(*Open) *p_err); (1) (FS_NAND_CTRLR_GEN_DATA void FS_ERR *p_ctrlr_data, *p_ext_cfg, *p_err); (2) void (*Close) (void *p_ext_data); (3) FS_NAND_PG_SIZE (*Setup) (FS_NAND_CTRLR_GEN_DATA void FS_ERR *p_ctrlr_data, *p_ext_data, *p_err); (4) void (*RdStatusChk) (void FS_ERR *p_ext_data, *p_err); (5) void (*ECC_Calc) (void void void FS_NAND_PG_SIZE FS_ERR *p_ext_data, *p_sec_buf, *p_oos_buf, oos_size, *p_err); (6) void (*ECC_Verify) (void void void FS_NAND_PG_SIZE FS_ERR *p_ext_data, *p_sec_buf, *p_oos_buf, oos_size, *p_err); (7) } FS_NAND_CTLRR_GEN_EXT; Listing 13-10 API structure type for generic controller extension 191 600-uC-FS-001.book Page 192 Wednesday, October 10, 2012 12:03 PM Chapter 13 L13-10(1) The Init() funtion provides an opportunity to initialize an extension. This will be called only once, when the extension is registered with the generic controller (during FSDev_Open()). If multiple generic controller instances are configured with the same extension, the Init() function will still be called only once. L13-10(2) The Open() function is called by the generic controller's own Open() function. This function will also receive the controller extension configuration pointer. L13-10(3) The Close() function might be called by the generic controller's own Close() function and allow the extension to release its resources. Close() will typically never be called. L13-10(4) The Setup() function is called during the generic controller's own Setup() function and provides an opportunity to setup some internal parameters according to the generic controller's operating conditions. The generic controller's instance data is provided as an argument to this function. The function must return the amount of required OOS storage space, in octets (ECC data, for example). L13-10(5) The RdStatusChk() function is called after a sector read operation, by the generic controller's SecRd() function. It should determine if a read error has occurred and return an error accordingly. L13-10(6) The ECC_Calc() function is called before a sector is written to the NAND device by the generic controller's SecWr() function, and provides an opportunity to calculate the ECC data and to append it to the OOS metadata. L13-10(7) The ECC_Verify() function is called after a sector is read from the NAND device by the generic controller's SecRd() function. It should read the ECC data from the OOS metadata, verify the sector and OOS data integrity, and correct any errors found if possible. It should return an appropriate error code if ECC errors are found. 192 600-uC-FS-001.book Page 193 Wednesday, October 10, 2012 12:03 PM Development Guide 13-8-3 ECC MODULE DEVELOPMENT GUIDE Before undertaking the task of writing a software ECC module, or a software interface to a hardware ECC module, you should evaluate whether or not modifications to the controller layer are needed as well. Some hardware ECC modules integrated within a NAND device or a micro-controller's memory controller can be handled through a generic controller extension module. However, if your ECC module can be interfaced with the software ECC generic controller extension, you could limit the code to be developed to the ECC layer only. If this is the case, you will need to provide the implementation of the API as shown in Listing 13-11: typedef struct ecc_calc { CPU_SIZE_T BufLenMin; CPU_SIZE_T BufLenMax; CPU_INT08U ECC_Len; CPU_INT08U NbrCorrectableBits; ECC_CALC_FNCT Calc; ECC_CHK_FNCT Chk; ECC_CORRECT_FNCT Correct; } ECC_CALC; (1) (2) (3) (4) (5) (6) (7) Listing 13-11 ECC API type definition L13-11(1) Minimum buffer length that the ECC module can handle. L13-11(2) Maximum buffer length that the ECC module can handle. L13-11(3) Length, in octets, of the code for a single buffer. L13-11(4) Number of bits the module can correct for each buffer. L13-11(5) Pointer to the code calculation function. L13-11(6) Pointer to the error detection function. L13-11(7) Pointer to the error correction function. For more details on the implementation, please refer to the C/CRC User Manual. 193 600-uC-FS-001.book Page 194 Wednesday, October 10, 2012 12:03 PM Chapter 13 13-8-4 CONTROLLER LAYER DEVELOPMENT GUIDE To fully take advantage of advanced peripherals (for example, NAND flash controllers), you might decide to provide your own implementation of the controller layer. The controller layer is one level above the BSP layer. Its interface is more flexible, but is also more complex to implement. If you choose that route, it is strongly recommended to use the provided implementations as an example. Listing 13-12 describes the API that must be implemented for the controller layer. 194 600-uC-FS-001.book Page 195 Wednesday, October 10, 2012 12:03 PM Development Guide typedef struct void fs_nand_ctrlr_api { *(*Open) void FS_NAND_PART_DATA (FS_NAND_PART_API void void FS_ERR *p_part_api, *p_bsp_api, *p_ctrlr_cfg, *p_err); (void *p_ctrlr_data); *(*PartDataGet) (void *p_ctrlr_data); (*Close) FS_NAND_PG_SIZE (*Setup) (void FS_NAND_PG_SIZE FS_ERR *p_ctrlr_data, sec_size, *p_err); void (*SecRd) (void void void FS_SEC_NBR FS_ERR *p_ctrlr_data, *p_dest, *p_dest_oos, sec_ix_phy, *p_err); void (*OOSRdRaw) (void void FS_SEC_NBR FS_NAND_PG_SIZE FS_NAND_PG_SIZE FS_ERR *p_ctrlr_data, *p_dest_oos, sec_nbr_phy, offset, length, *p_err); void (*SpareRdRaw) (void void FS_SEC_QTY FS_NAND_PG_SIZE FS_NAND_PG_SIZE FS_ERR *p_ctrlr_data, *p_dest_oos, pg_nbr_phy, offset, length, *p_err); void (*SecWr) (void void void FS_SEC_NBR FS_ERR *p_ctrlr_data, *p_src, *p_src_spare, sec_nbr_phy, *p_err); void (*BlkErase) (void CPU_INT32U FS_ERR *p_ctrlr_data, blk_nbr_phy, *p_err); void (*IO_Ctrl) (void CPU_INT08U void FS_ERR *p_ctrlr_data, cmd, *p_buf, *p_err); } FS_NAND_CTRLR_API; Listing 13-12 Controller API type definition 195 600-uC-FS-001.book Page 196 Wednesday, October 10, 2012 12:03 PM Chapter 13 Before implementing the following functions, it is important to understand the difference between out-of-sector (OOS) data and the spare area. In a NAND device, each page has a spare area, typically used to store metadata and error correction codes (ECC). The spare area also contains a factory defect mark and, optionally, reserved sections. In the implementation of the C/FS NAND driver, the OOS data is metadata sent to the controller layer by the translation layer. It must be stored in the spare area, without overwriting the bad block mark and without writing to the reserved section. It must also be protected by ECC. The OOS data is only a part of what is inside the spare area. It doesn't include the factory defect marks, the reserved sections and the ECC data. Also, if the sector size is not equal to the page size, the OOS data will be associated to a single sector, while the spare area will be associated to a single page. In that case, multiple OOS sections would be fit in a single spare area. OPEN/CLOSE FUNCTIONS The Open() and Close() function will be called respectively by FSDev_Open() and FSDev_Close(). Typically, FSDev_Open() is called during initialization and FSDev_Close() is never called. When implementing the Open() function of the controller layer, you should typically add all necessary code for the bus/controller initialization (or call the Open() function of the BSP layer). You should also allocate the necessary memory and perform all the operations that need to be done a single time only, when opening the device. The Close() function is typically left empty. PART DATA GET FUNCTION The PartDataGet() function should return an instance of the type FS_NAND_PART_DATA associated to a particular device. SETUP FUNCTION The Setup() function is called a single time, after the Open() function. It must perform the proper calculation to make sure that the out-of-sector data (OOS) and the error correction codes (ECC) can fit in the spare area. 196 600-uC-FS-001.book Page 197 Wednesday, October 10, 2012 12:03 PM Development Guide SECTOR READ FUNCTION The SectorRd() function must copy the data found at the physical sector sec_ix_phy into the p_dest buffer. It must also copy the out-of-sector data (OOS - the section of the spare area, excluding ECC, bad block marks and unused sections) into the p_dest_oos buffer. Before returning successfully, the function should check for errors and correct them, if needed (with ECC). OUT-OF-SECTOR (OOS) RAW READ FUNCTION The OOSRdRaw() function must copy len octets from the offset octet in the OOS of the sector sec_ix_phy into the p_dest_oos buffer. This function should not perform error correction. SPARE AREA RAW READ FUNCTION The SpareRdRaw() function must copy len octets from the offset octet in the spare area of the page pg_ix_phy into the p_dest_spare buffer. This function should not perform error correction. SECTOR WRITE FUNCTION The SectorWr() function must write the data found in the p_src buffer into the physical sector sec_ix_phy of the NAND device. It must also write the out-of-sector data (OOS - the section of the spare area, excluding ECC, bad block marks and unused sections) found in the p_src_oos buffer into the spare area. It should also store error correction codes (ECC) in the spare area. BLOCK ERASE FUNCTION The BlkErase() function should erase the block blk_ix_phy of the device. IO CONTROL FUNCTION The IO_Ctrl() function body can be left empty. It was created to perform device or controller specific commands without the need of a custom API. It can simply return the FS_ERR_DEV_INVALID_IO_CTRL error code. 197 600-uC-FS-001.book Page 198 Wednesday, October 10, 2012 12:03 PM Chapter 13 Note that the ONFI part layer implementation makes use of the FS_DEV_IO_CTRL_NAND_PARAM_PG_RD I/O control operation. In order to retain compatibility with the ONFI part layer implementation, your controller implementation must support that operation. 198 600-uC-FS-001.book Page 199 Wednesday, October 10, 2012 12:03 PM Chapter 14 NOR Flash Driver NOR flash is a low-capacity on-board storage solution. Traditional parallel NOR flash, located on the external bus of a CPU, offers extremely fast read performance, but comparatively slow writes (typically performed on a word-by-word basis). Often, these store application code in addition to providing a file system. The parallel architecture of traditional NOR flash restricts use to a narrow class of CPUs and may consume valuable PCB space. Increasingly, serial NOR flash are a valid alternative, with fast reads speeds and comparable capacities, but demanding less of the CPU and hardware, being accessed by SPI or SPI-like protocols. Table 14-1 briefly compares these two technologies; specific listings of supported devices are located in section 14-5 "Physical-Layer Drivers" on page 214. Device Category Typical Packages Manufacturers Description Parallel NOR Flash TSOP32, TSOP48, BGA48, TSOP56, AMD (Spansion) Intel (Numonyx) SST ST Parallel data (8- or 16-bit) and address bus (20+ bits). Most devices BGA56 (Numonyx) have CFI `query' information and use one of several standard command sets. Serial NOR Flash SOIC-8N, SOIC-8W, Atmel SST ST SPI or multi-bit SPI-like interface. SOIC-16, WSON, USON (Numonyx) Command sets are generally similar. Table 14-1 NOR flash devices 199 600-uC-FS-001.book Page 200 Wednesday, October 10, 2012 12:03 PM Chapter 14 14-1 FILES AND DIRECTORIES The files inside the RAM disk driver directory are outlined in this section; the generic file-system files, outlined in Chapter 3, "C/FS Directories and Files" on page 29, are also required. \Micrium\Software\uC-FS\Dev This directory contains device-specific files. \Micrium\Software\uC-FS\Dev\NOR This directory contains the NOR driver files. fs_dev_nor.* These files are device driver for NOR flash devices. This file requires a set of BSP functions be defined in a file named fs_dev_nor_bsp.c to work with a certain hardware setup. .\BSP\Template\fs_dev_nor_bsp.c This is a template BSP for traditional parallel NOR devices. See section C-10 "NOR Flash BSP" on page 473 for more information. .\BSP\Template (SPI)\fs_dev_nor_bsp.c This is a template BSP for serial (SPI) NOR devices. See section C-11 "NOR Flash SPI BSP" on page 480 for more information. .\BSP\Template (SPI GPIO)\fs_dev_nor_bsp.c This is a template BSP for serial (SPI) NOR devices using GPIO (bit-banging). See section C-11 "NOR Flash SPI BSP" on page 480 for more information. 200 600-uC-FS-001.book Page 201 Wednesday, October 10, 2012 12:03 PM Files and Directories .\PHY This directory contains physical-level drivers for specific NOR types: fs_dev_nor_amd_1x08.* CFI-compatible parallel NOR implementing AMD command set (1 chip, 8-bit data bus) fs_dev_nor_amd_1x16.* CFI-compatible parallel NOR implementing AMD command set (1 chip, 16-bit data bus) fs_dev_nor_intel.* CFI-compatible parallel NOR implementing Intel command set (1 chip, 16-bit data bus) fs_dev_nor_sst39.* SST SST39 Multi-Purpose Flash fs_dev_nor_stm25.* ST STM25 serial flash fs_dev_nor_sst25.* SST SST25 serial flash \Micrium\Software\uC-FS\Examples\BSP\Dev\NOR Each subdirectory contains an example BSP for a particular platform. These are named according to the following rubric: <Chip Manufacturer>\<Board or CPU>\fs_dev_nor_bsp.c 201 600-uC-FS-001.book Page 202 Wednesday, October 10, 2012 12:03 PM Chapter 14 14-2 DRIVER AND DEVICE CHARACTERISTICS NOR devices, no matter what attachment interface (serial or parallel), share certain characteristics. The medium is always organized into units (called blocks) which are erased at the same time; when erased, all bits are 1. Only an erase operation can change a bit from a 0 to a 1, but any bit can be individually programmed from a 1 to a 0. The C/FS driver requires that any 2-byte word can be individually accessed (read or programmed). The driver RAM requirement depends on flash parameters such as block size and run-time configurations such as sector size. For a particular instance, a general formula can give an approximate: if (secs_per_blk < 255) { temp1 = ceil(blk_cnt_used / 8) + (blk_cnt_used * 1); } else { temp1 = ceil(blk_cnt_used / 8) + (blk_cnt_used * 2); } if (sec_cnt < 65535) { temp2 = sec_cnt * 2; } else { temp2 = sec_cnt * 4; } temp3 = sec_size; TOTAL = temp1 + temp2 + temp3; where secs_per_blk The number of sectors per block. blk_cnt_used The number of blocks on the flash which will be used for the file system. sec_cnt The total number of sectors on the device. sec_size The sector size configured for the device, in octets. 202 600-uC-FS-001.book Page 203 Wednesday, October 10, 2012 12:03 PM Driver and Device Characteristics secs_per_blk and sec_cnt can be calculated from more basic parameters: secs_per_blk = floor(blk_size / sec_size); sec_cnt = secs_per_blk * blk_cnt_used; where blk_size The size of a block on the device, in octets Take as an example a 16-Mb NOR that is entirely dedicated to file system usage, with a 64-KB block size, configured with a 512-B sector. The following parameters describe the format: blk_cnt_used blk_size sec_size secs_per_blk sec_cnt = = = = = 32; 65536; 512; 65536 / 512 = 128; 128 * 32 = 4096; and the RAM usage is approximately temp1 temp2 temp3 TOTAL = = = = (32 / 8) + (32 * 2) = 68; 4096 * 2 = 8192; 512; 68 + 8192 + 512 = 8772; In this example, as in most situations, increasing the sector size will decrease the RAM usage. If the sector size were 1024-B, only 5188-B would have been needed, but a moderate performance penalty would be paid. 203 600-uC-FS-001.book Page 204 Wednesday, October 10, 2012 12:03 PM Chapter 14 14-3 USING A PARALLEL NOR DEVICE To use the NOR driver, five files, in addition to the generic file system files, must be included in the build: fs_dev_nor.c. fs_dev_nor.h. fs_dev_nor_bsp.c (located in the user application or BSP). A physical-layer driver (e.g., as provided in \Micrium\Software\uC-FS\Dev\NOR\PHY) The file fs_dev_nor.h must also be #included in any application or header files that directly reference the driver (for example, by registering the device driver). The following directories must be on the project include path: \Micrium\Software\uC-FS\Dev\NOR \Micrium\Software\uC-FS\Dev\NOR\PHY A single NOR volume is opened as shown in Table 14-1. The file system initialization (FS_Init()) function must have previously been called. ROM characteristics and performance benchmarks of the NOR driver can be found in section 9-1-1 "Driver Characterization" on page 113. The NOR driver also provides interface functions to perform low-level operations (see section A-12 "FAT System Driver Functions" on page 386). 204 600-uC-FS-001.book Page 205 Wednesday, October 10, 2012 12:03 PM Using a Parallel NOR Device CPU_BOOLEAN App_FS_AddNOR (void) { FS_DEV_NOR_CFG nor_cfg; FS_ERR err; FS_DevDrvAdd((FS_DEV_API *)&FSDev_Nor, (FS_ERR *)&err); /* (1) */ if ((err != FS_ERR_NONE) && (err != FS_ERR_DEV_DRV_ALREADY_ADDED)) { return (DEF_FAIL); } nor_cfg.AddrBase nor_cfg.RegionNbr nor_cfg.AddrStart nor_cfg.DevSize nor_cfg.SecSize = = = = = nor_cfg.PctRsvd = nor_cfg.PctRsvdSecActive = nor_cfg.EraseCntDiffTh = nor_cfg.PhyPtr nor_cfg.BusWidth nor_cfg.BusWidthMax nor_cfg.PhyDevCnt nor_cfg.MaxClkFreq /* (2) APP_CFG_FS_NOR_ADDR_BASE; APP_CFG_FS_NOR_REGION_NBR; APP_CFG_FS_NOR_ADDR_START; APP_CFG_FS_NOR_DEV_SIZE; APP_CFG_FS_NOR_SEC_SIZE; */ APP_CFG_FS_NOR_PCT_RSVD; APP_CFG_FS_NOR_PCT_RSVD_SEC_ACTIVE; APP_CFG_FS_NOR_ERASE_CNT_DIFF_TH; = (FS_DEV_NOR_PHY_API *)APP_CFG_FS_NOR_PHY_PTR; = APP_CFG_FS_NOR_BUS_WIDTH; = APP_CFG_FS_NOR_BUS_WIDTH_MAX; = APP_CFG_FS_NOR_PHY_DEV_CNT; = APP_CFG_FS_NOR_MAX_CLK_FREQ; FSDev_Open((CPU_CHAR *)"nor:0:", (void *)&nor_cfg, (FS_ERR *)&err); /* (3) */ /* (a) */ /* (b) */ switch (err) { case FS_ERR_NONE: APP_TRACE_DBG((" ...opened device.\r\n")); break; case FS_ERR_DEV_INVALID_LOW_FMT: /* Low fmt invalid. */ APP_TRACE_DBG((" ...opened device (not low-level formatted).\r\n")); FSDev_NOR_LowFmt("nor:0:", &err); /* (4) */ if (err != FS_ERR_NONE) { APP_TRACE_DBG((" ...low-level format failed.\r\n")); return (DEF_FAIL); } break; default: /* Device error. */ APP_TRACE_DBG((" ...opening device failed w/err = %d.\r\n\r\n", err)); return (DEF_FAIL); } 205 600-uC-FS-001.book Page 206 Wednesday, October 10, 2012 12:03 PM Chapter 14 /* (5) FSVol_Open((CPU_CHAR *)"nor:0:", (CPU_CHAR *)"nor:0:", (FS_PARTITION_NBR ) 0, (FS_ERR *)&err); /* /* /* */ (a) */ (b) */ (c) */ switch (err) { case FS_ERR_NONE: APP_TRACE_DBG((" ...opened volume (mounted).\r\n")); break; case FS_ERR_PARTITION_NOT_FOUND: /* Volume error. */ APP_TRACE_DBG((" ...opened device (not formatted).\r\n")); FSVol_Fmt("nor:0:", (void *)0, &err); /* (6) */ if (err != FS_ERR_NONE) { APP_TRACE_DBG((" ...format failed.\r\n")); return (DEF_FAIL); } break; default: /* Device error. */ APP_TRACE_DBG((" ...opening volume failed w/err = %d.\r\n\r\n", err)); return (DEF_FAIL); } return (DEF_OK); } Listing 14-1 Opening a NOR device volume L14-1(1) Register the NOR device driver FSDev_NOR. L14-1(2) The NOR device configuration should be assigned. For more information about these parameters, see section D-3 "FS_DEV_NOR_CFG" on page 485. L14-1(3) FSDev_Open() opens/initializes a file system device. The parameters are the device name (3a) and a pointer to a device driver-specific configuration structure (3b). The device name (3a) s composed of a device driver name ("nor"), a single colon, an ASCII-formatted integer (the unit number) and another colon. L14-1(4) FSDev_NOR_LowFmt() low-level formats a NOR. If the NOR has never been used with C/FS, it must be low-level formatted before being used. Low-level formatting will associate logical sectors with physical areas of the device. 206 600-uC-FS-001.book Page 207 Wednesday, October 10, 2012 12:03 PM Using a Parallel NOR Device FSVol_Open() opens/mounts a volume. The parameters are the volume name (5a), the device name (5b) and the partition that will be opened (5c). There is no restriction on the volume name (5a); however, it is typical to give the volume the same name as the underlying device. If the default partition is to be opened, or if the device is not partition, then the partition number (5c) should be zero. FSVol_Fmt() formats a file system device. If the NOR has just been low-level format, it will have no file system on it after it is opened (it will be unformatted) and must be formatted before files can be created or accessed. If the NOR initialization succeeds, the file system will produce the trace output as shown in Figure 14-1 (if a sufficiently high trace level is configured). See section E-9 "Trace Configuration" on page 507 about configuring the trace level. Figure 14-1 NOR detection trace output 207 600-uC-FS-001.book Page 208 Wednesday, October 10, 2012 12:03 PM Chapter 14 14-3-1 DRIVER ARCHITECTURE When used with a parallel NOR device, the NOR driver is three layered, as depicted in the figure below. The generic NOR driver, as always, provides sector abstraction and performs wear-leveling (to make certain all blocks are used equally). Below this, the physical-layer driver implements a particular command set to read and program the flash and erase blocks. Lastly, a BSP implements function to initialize and unitialize the bus interface. Device commands are executed by direct access to the NOR, at locations appropriately offset from the configured base address. NOR Driver fs_dev_nor.c/h Provides generic driver interface (e.g., init, read, write) and performs wearleveling so all blocks are used equally. Physical-Layer Driver fs_dev_nor_amd_1x16.* fs_dev_nor_cfi_intel.* fs_dev_nor_cfi_sst39.* Implements particular NOR flash command set; accesses NOR directly on bus interface. Bus interface BSP NOR fs_dev_nor_bsp.c Initialize/uninitialize bus interface. Figure 14-2 NOR driver architecture (parallel NOR flash) 14-3-2 HARDWARE Parallel NOR devices typically connect to a host MCU/MPU via an external bus interface (EBI), with an 8- or 16-bit data lines and 20 or more address lines (depending on the device size). Many silicon vendors offer parallel NOR product lines; most devices currently marketed are conformant to the Common Flash Interface (CFI). A set of query information allows the C/FS NOR driver physical-layer drivers to interface with almost any NOR flash without configuration or modification. The standard query information provides the following details: 208 600-uC-FS-001.book Page 209 Wednesday, October 10, 2012 12:03 PM Using a Parallel NOR Device Command set. Three different command sets are common: Intel, AMD and SST. All three are supported. Geometry. A device is composed of one or more regions of identically-sized erase blocks. Uniform devices contain only one region. Boot-block devices often have one or two regions of small blocks for code storage at the top or bottom of the device. All of these are supported by the NOR driver. Offset Length (Bytes) Contents 0x10 1 Query string "Q" 0x11 1 Query string "R" 0x12 1 Query string "Y" 0x13 2 Command set 0x27 1 Device size, in bytes = 2n 0x2A 2 Maximum number of bytes in multi-byte write = 2N 0x2C 1 Number of erase block regions = m 0x2D 2 Region 1: Number of erase blocks = x + 1 0x2F 2 Region 1: Size of each erase block = y * 256 (bytes) 0x31 2 Region 2: Number of erase blocks = x + 1 0x33 2 Region 2: Size of each erase block = y * 256 (bytes) 0x2D + (m-1) * 4 2 Region m: Number of erase blocks = x + 1 0x2F + (m-1) * 4 2 Region m: Size of each erase block = y * 256 (bytes) . . . Table 14-2 CFI query information Table 14-2 gives the format of CFI query information. The first three bytes should constitute the marker string "QRY", by which the retrieval of correct parameters is verified. A two-byte command set identifier follows; this must match the identifier for the command set supported by the physical-layer driver. Beyond is the geometry information: the device size, the number of erase block regions, and the size and number of blocks in each region. For most flash, these regions are contiguous and sequential, the first at the beginning of the device, the second just after. Since this is not always true (see section 14-5-3 209 600-uC-FS-001.book Page 210 Wednesday, October 10, 2012 12:03 PM Chapter 14 "FSDev_NOR_SST39" on page 216 for an example), the manufacturer's information should always be checked and, for atypical devices, the physical-layer driver copied to the application directory and modified. Command Set Identifier Description 0x0001 Intel 0x0002 AMD/Spansion 0x0003 Intel 0x0102 SST Table 14-3 Common command sets 14-3-3 NOR BSP OVERVIEW A BSP is required so that a physical-layer driver for a parallel flash will work on a particular system. The functions shown in the table below must be implemented. Pleaser refer to section C-10 "NOR Flash BSP" on page 473 for the details about implementing your own BSP. Function Description FSDev_NOR_BSP_Open() Open (initialize) bus for NOR. FSDev_NOR_BSP_Close() Close (uninitialize) bus for NOR. FSDev_NOR_BSP_Rd_XX() Read from bus interface. FSDev_NOR_BSP_RdWord_XX() Read word from bus interface. FSDev_NOR_BSP_WrWord_XX() Write word to bus interface FSDev_NOR_BSP_WaitWhileBusy() Wait while NOR is busy. Table 14-4 NOR BSP functions The Open()/Close() functions are called upon open/close; these calls are always matched. The remaining functions (Rd_XX(), RdWord_XX(), WrWord_XX()) read data from or write data to the NOR. If a single parallel NOR device will be accessed, these function may be defined as macros to speed up bus accesses. 210 600-uC-FS-001.book Page 211 Wednesday, October 10, 2012 12:03 PM Using a Serial NOR Device 14-4 USING A SERIAL NOR DEVICE When used with a serial NOR device, the NOR driver is three layered, as depicted in the figure below. The generic NOR driver, as always, provides sector abstraction and performs wear-leveling (to make certain all blocks are used equally). Below this, the physical-layer driver implements a particular command set to read and program the flash and erase blocks. Lastly, a BSP implements function to communicate with the device over SPI. Device commands are executed though this BSP. NOR Driver fs_dev_nor.c/h Provides generic driver interface (e.g., init, read, write) and performs wearleveling so all blocks are used equally. Physical-Layer Driver fs_dev_nor_stm25.* fs_dev_nor_sst25.* Implements particular serial NOR flash command set; accesses NOR through SPI interface. SPI BSP fs_dev_nor_bsp.c Implements SPI communication for a particular MCU/MPU. Figure 14-3 NOR driver architecture (serial NOR flash) 211 600-uC-FS-001.book Page 212 Wednesday, October 10, 2012 12:03 PM Chapter 14 14-4-1 HARDWARE Serial NOR devices typically connect to a host MCU/MPU via an SPI or SPI-like bus. Eight-pin devices, with the functions listed in Table 14-5, or similar, are common, and are often employed with the HOLD and WP pins held high (logic low, or inactive), as shown in Table 14-5. As with any SPI device, four signals are used to communicate with the host (CS, SI, SCK and SO). MCU/MPU SERIAL NOR ___ CS CS VCC _______ MISO SO HOLD ____ MOSI WP SCK VSS SCK SI Figure 14-4 Typical serial NOR connections 212 600-uC-FS-001.book Page 213 Wednesday, October 10, 2012 12:03 PM Using a Serial NOR Device 14-4-2 NOR SPI BSP OVERVIEW An NOR BSP is required so that a physical-layer driver for a serial flash will work on a particular system. For more information about these functions, see section C-11 on page 480. Function Description FSDev_NOR_BSP_SPI_Open() Open (initialize) SPI. FSDev_NOR_BSP_SPI_Close() Close (uninitialize) SPI. FSDev_NOR_BSP_SPI_Lock() Acquire SPI lock. FSDev_NOR_BSP_SPI_Unlock() Release SPI lock. FSDev_NOR_BSP_SPI_Rd() Read from SPI. FSDev_NOR_BSP_SPI_Wr() Write to SPI. FSDev_NOR_BSP_SPI_ChipSelEn() Enable chip select. FSDev_NOR_BSP_SPI_ChipSelDis() Disable chip select. FSDev_NOR_BSP_SPI_SetClkFreq() Set SPI clock frequency. Table 14-5 NOR SPI BSP functions 213 600-uC-FS-001.book Page 214 Wednesday, October 10, 2012 12:03 PM Chapter 14 14-5 PHYSICAL-LAYER DRIVERS The physical-layer drivers distributed with the NOR driver (see the table below) support a wide variety of parallel and serial flash devices from major vendors. Whenever possible, advanced programming algorithms (such as the common buffered programming commands) are used to optimize performance. Within the diversity of NOR flash, some may be found which implement the basic command set, but not the advanced features; for these, a released physical-layer may need to be modified. In all cases, the manufacturer's reference should be compared to the driver description below. Driver API Files Description FSDev_NOR_AMD_1x08 fs_dev_nor_amd_1x08.* Supports CFI-compatible devices with 8-bit data bus implementing AMD command set. FSDev_NOR_AMD_1x16 fs_dev_nor_amd_1x16.* Supports CFI-compatible devices i with 16-bit data bus mplementing AMD command set. FSDev_NOR_Intel_1x16 fs_dev_nor_intel.* Supports CFI-compatible devices i with 16-bit data bus mplementing Intel command set. FSDev_NOR_SST39 fs_dev_nor_sst39.* Supports various SST SST39 devices with 16-bit data bus. FSDev_NOR_STM29_1x08 fs_dev_nor_stm29_1x08.* Supports various ST M29 devices with 8-bit data bus. FSDev_NOR_STM29_1x16 fs_dev_nor_stm29_1x16.* Supports various ST M29 devices with 16-bit data bus. FSDev_NOR_STM25 fs_dev_nor_stm25.* Supports various ST M25 serial devices. FSDev_NOR_SST25 fs_dev_nor_sst25.* Supports various SST SST25 serial devices. Table 14-6 Physical-layer drivers 214 600-uC-FS-001.book Page 215 Wednesday, October 10, 2012 12:03 PM Physical-Layer Drivers 14-5-1 FSDEV_NOR_AMD_1X08, FSDEV_NOR_AMD_1X16 FSDev_NOR_AMD_1x08 and FSDev_NOR_AMD_1x16 support CFI NOR flash implementing AMD command set, including: Most AMD and Spansion devices Most ST/Numonyx devices Others The fast programming command "write to buffer and program", supported by many flash implementing the AMD command set, is used in this driver if the "Maximum number of bytes in a multi-byte write" (in the CFI device geometry definition) is non-zero. Some flash implementing AMD command set have non-zero multi-byte write size but do not support the "write to buffer & program" command. Often these devices will support alternate fast programming methods. This driver MUST be modified for those devices, to ignore the multi-byte write size in the CFI information. Define NOR_NO_BUF_PGM to force this mode of operation. 14-5-2 FSDEV_NOR_INTEL_1X16 FSDev_NOR_Intel_1x16 supports CFI NOR flash implementing Intel command set, including Most Intel/Numonyx devices Some ST/Numonyx M28 device Others 215 600-uC-FS-001.book Page 216 Wednesday, October 10, 2012 12:03 PM Chapter 14 14-5-3 FSDEV_NOR_SST39 FSDev_NOR_SST39 supports SST's SST39 Multi-Purpose Flash memories, as described in various datasheets at SST (http://www.sst.com). SST39 devices use a modified form of the AMD command set. A more significant deviation is in the CFI device geometry information, which describes two different views of the memory organization--division in to small sectors and division into large blocks--rather than contiguous, separate regions. The driver always uses the block organization. 14-5-4 FSDEV_NOR_STM25 FSDev_NOR_STM25 supports Numonyx/ST's M25 & M45 serial flash memories, as described in various datasheets at Numonyx (http://www.numonyx.com). This driver has been tested with or should work with the devices in the table below. The M25P-series devices are programmed on a page (256-byte) basis and erased on a sector (32- or 64-KB) basis. The M25PE-series devices are also programmed on a page (256-byte) basis, but are erased on a page, subsector (4-KB) or sector (64-KB) basis. Manufacturer Device Capacity Block Size Block Count ST M25P10 1 Mb 64-KB 2 ST M25P20 2 Mb 64-KB 4 ST M25P40 4 Mb 64-KB 8 ST M25P80 8 Mb 64-KB 16 ST M25P16 16 Mb 64-KB 32 ST M25P32 32 Mb 64-KB 64 ST M25P64 64 Mb 64-KB 128 ST M25P128 128 Mb 64-KB 256 ST M25PE10 1 Mb 64-KB 2 ST M25PE20 2 Mb 64-KB 4 ST M25PE40 4 Mb 64-KB 8 ST M25PE80 8 Mb 64-KB 16 ST M25PE16 16 Mb 64-KB 32 Table 14-7 Supported M25 serial flash 216 600-uC-FS-001.book Page 217 Wednesday, October 10, 2012 12:03 PM Physical-Layer Drivers 14-5-5 FSDEV_NOR_SST25 FSDev_NOR_SST25 supports SST's SST25 serial flash memories, as described in various datasheets at Numonyx (http://www.numonyx.com). This driver has been tested with or should work with the devices in the table below. The M25P-series devices are programmed on a word (2-byte) basis and erased on a sector (4-KB) or block (32-KB) basis. The revision A devices and revision B devices differ slightly. Both have an Auto-Address Increment (AAI) programming mode. In revision A devices, the programming is performed byte-by-byte; in revision B devices, word-by-word. Revision B devices can also be erased on a 64-KB block basis and support a command to read a JEDEC-compatible ID. Manufacturer Device Capacity Block Size Block Count SST SST25VF010B 1 Mb 4-KB 32 SST SST25VF020B 2 Mb 4-KB 64 SST SST25VF040B 4 Mb 4-KB 128 SST SST25VF080B 8 Mb 32-KB 32 SST SST25VF016B 16 Mb 32-KB 64 SST SST25VF032B 32 Mb 32-KB 128 Table 14-8 Supported SST25 serial flash 217 600-uC-FS-001.book Page 218 Wednesday, October 10, 2012 12:03 PM Chapter 14 218 600-uC-FS-001.book Page 219 Wednesday, October 10, 2012 12:03 PM Chapter 15 MSC Driver The MSC driver supports USB mass storage class devices (i.e., USB drives, thumb drives) using the C/USB host stack. 15-1 FILES AND DIRECTORIES The files inside the MSC driver directory are outlined in this section; the generic file-system files, outlined in Chapter 3, "C/FS Directories and Files" on page 29, are also required. \Micrium\Software\uC-FS\Dev This directory contains device-specific files. \Micrium\Software\uC-FS\Dev\MSC This directory contains the MSC driver files. fs_dev_msc.* constitute the MSC device driver. \Micrium\Software\uC-USB This directory contains the code for C/USB. For more information, please see the C/USB user manual. 219 600-uC-FS-001.book Page 220 Wednesday, October 10, 2012 12:03 PM Chapter 15 15-2 USING THE MSC DRIVER To use the MSC driver, two files, in addition to the generic file system files, must be included in the build: fs_dev_msc.c. fs_dev_msc.h. The file fs_dev_msc.h must also be #included in any application or header files that directly reference the driver (for example, by registering the device driver). The following directory must be on the project include path: \Micrium\Software\uC-FS\Dev\MSC Before C/FS is initialized, the C/USB host stack must be initialized as shown in Listing 15-1. The file system initialization function (FS_Init()) must then be called and the MSC driver, FSDev_MSC, restivered (using FS_DevDrvAdd()). The USB notification function should add/remove devices when events occur, as shown in Listing 15-1. ROM/RAM characteristics and performance benchmarks of the MSC driver can be found in section 9-1-1 "Driver Characterization" on page 113. static void App_InitUSB_Host (void) { USBH_ERR err; err = USBH_HostCreate(&App_USB_Host, &USBH_AT91SAM9261_Drv); if (err != USBH_ERR_NONE) { return; } err = USBH_HostInit(&App_USB_Host); if (err != USBH_ERR_NONE) { return; } USBH_ClassDrvReg(&App_USB_Host, &USBH_MSC_ClassDrv, (USBH_CLASS_NOTIFY_FNCT)App_USB_HostMSC_ClassNotify, (void *)0); } Listing 15-1 Example C/USB initialization 220 600-uC-FS-001.book Page 221 Wednesday, October 10, 2012 12:03 PM Using the MSC Driver static void App_USB_HostMSC_ClassNotify (void CPU_INT08U void *pclass_dev, is_conn, *pctx) { USBH_MSC_DEV USBH_ERR *p_msc_dev; usb_err; FS_ERR fs_err; p_msc_dev = (USBH_MSC_DEV *)pclass_dev; switch (is_conn) { case USBH_CLASS_DEV_STATE_CONNECTED: /* ----- MASS STORAGE DEVICE CONN'D ----- */ usb_err = USBH_MSC_RefAdd(p_msc_dev); if (usb_err == USBH_ERR_NONE) { FSDev_MSC_DevOpen(p_msc_dev, &fs_err); } break; case USBH_CLASS_DEV_STATE_REMOVED: FSDev_MSC_DevClose(p_msc_dev); USBH_MSC_RefRel(p_msc_dev); /* ----- MASS STORAGE DEVICE REMOVED ---- */ break; default: break; } } Listing 15-2 C/USB MSC notification function If the file system and USB stack initialization succeed, the file system will produce the trace output as shown in Figure 15-1 (if a sufficiently high trace level is configured) when the a MSC device is connected. See section E-9 "Trace Configuration" on page 507 about configuring the trace level. Figure 15-1 MSC detection trace output 221 600-uC-FS-001.book Page 222 Wednesday, October 10, 2012 12:03 PM Chapter 15 222 600-uC-FS-001.book Page 223 Wednesday, October 10, 2012 12:03 PM Appendix A C/FS API Reference This chapter provides a reference to C/FS services. The following information is provided for each entry: A brief description of the service The function prototype The filename of the source code The #define constant required to enable code for the service A description of the arguments passed to the function A description of returned value(s) Specific notes and warnings regarding use of the service One or two examples of how to use the function Many functions return error codes. These error codes should be checked by the application to ensure that the C/FS function performed its operation as expected. Each of the user-accessible file system services is presented in alphabetical order within an appropriate section; the section for a particular function can be determined from its name. 223 600-uC-FS-001.book Page 224 Wednesday, October 10, 2012 12:03 PM Appendix A Section Functions begin with... General file system functions FS_ POXIX API functions fs_ Device functions FSDev_ Directory functions FSDir_ Entry functions FSEntry_ File functions FSFile_ Time functions FSTime_ Volume functions FSVol_ RAMDisk driver functions FSDev_RAM_ NAND driver functions FS_NAND SD/MMC driver functions FSDev_SD_ NAND driver functions FSDev_NAND_ NOR driver functions FSDev_NOR_ MSC driver functions FSDev_MSC_ FAT functions FS_FAT_ BSP functions FS_BSP_ OS functions FS_OS_ 224 600-uC-FS-001.book Page 225 Wednesday, October 10, 2012 12:03 PM A-1 GENERAL FILE SYSTEM FUNCTIONS void FS_DevDrvAdd (FS_DEV_API *p_dev_api, FS_ERR *p_err); FS_ERR FS_Init (FS_CFG CPU_INT08U FS_VersionGet (void); *p_fs_cfg); void FS_WorkingDirGet (CPU_CHAR *path_dir, CPU_SIZE_T len_max, FS_ERR *p_err); void FS_WorkingDirSet (CPU_CHAR FS_ERR void FS_DevDrvAdd *path_dir, *p_err); (FS_DEV_API *p_dev_drv, FS_ERR *p_err); 225 600-uC-FS-001.book Page 226 Wednesday, October 10, 2012 12:03 PM Appendix A A-1-1 FS_DevDrvAdd() void FS_DevDrvAdd (FS_DEV_API *p_dev_drv, FS_ERR *p_err); File Called from Code enabled by fs.c Application N/A Adds a device driver to the file system. ARGUMENTS p_dev_drv Pointer to device driver (see Section C.08). p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_DEV_DRV_ALREADY_ADDED FS_ERR_DEV_DRV_INVALID_NAME FS_ERR_DEV_DRV_NO_TBL_POS_AVAIL Device driver added. Argument p_dev_drv passed a NULL pointer. Device driver already added. Device driver name invalid. No device driver table position available. RETURNED VALUE None. NOTES/WARNINGS 226 The NameGet() device driver interface function MUST return a valid name: The name must be unique (e.g., a name that is not returned by any other device driver); The name must NOT include any of the characters: `:', `\' or `/'. The name must contain fewer than FS_CFG_MAX_DEV_DRV_NAME_LEN characters; The name must NOT be an empty string. The Init() device driver interface function is called to initialize driver structures and any hardware for detecting the presence of devices (for a removable medium). 600-uC-FS-001.book Page 227 Wednesday, October 10, 2012 12:03 PM A-1-2 FS_Init() FS_ERR FS_Init (FS_CFG *p_fs_cfg); File Called from Code enabled by fs.h Application N/A Initializes C/FS and MUST be called prior to calling any other C/FS API functions. ARGUMENTS p_fs_cfg Pointer to file system configuration (see Section C.01). RETURNED VALUE FS_ERR_NONE, if successful; Specific initialization error code, otherwise. The return value SHOULD be inspected to determine whether C/FS is successfully initialized or not. If /FS did NOT successfully initialize, search for the returned error in fs_err.h and source files to locate where C/FS initialization failed. NOTES/WARNINGS C/LIB memory management function Mem_Init() MUST be called prior to calling this function. 227 600-uC-FS-001.book Page 228 Wednesday, October 10, 2012 12:03 PM Appendix A A-1-3 FS_VersionGet() CPU_INT16U FS_VersionGet (void); File Called from Code enabled by fs.c Application N/A Gets the C/FS software version. ARGUMENTS None. RETURNED VALUE C/FS software version. NOTES/WARNINGS The value returned is multiplied by 100. For example, version 4.03 would be returned as 403. 228 600-uC-FS-001.book Page 229 Wednesday, October 10, 2012 12:03 PM A-1-4 FS_WorkingDirGet() void FS_WorkingDirGet (CPU_CHAR *path_dir, CPU_SIZE_T size, FS_ERR *p_err); File Called from Code enabled by fs.c Application; fs_getcwd() FS_CFG_WORKING_DIR_EN Get the working directory for the current task. ARGUMENTS path_dir String buffer that will receive the working directory path. size Size of string buffer. p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_NULL_ARG FS_ERR_NAME_BUF_TOO_SHORT FS_ERR_VOL_NONE_EXIST Working directory obtained. Argument path_dir passed a NULL pointer. Argument size passed a NULL value. Argument size less than length of path No volumes exist. RETURNED VALUE None. NOTES/WARNINGS If no working directory is assigned for the task, the default working directory--the root directory on the default volume--will be returned in the user buffer and set as the task's working directory. 229 600-uC-FS-001.book Page 230 Wednesday, October 10, 2012 12:03 PM Appendix A A-1-5 FS_WorkingDirSet() void FS_WorkingDirSet (CPU_CHAR *path_dir, FS_ERR *p_err); File Called from Code enabled by fs.c Application; FS_CFG_WORKING_DIR_EN fs_chdir() Set the working directory for the current task. ARGUMENTS path_dir String buffer that specified EITHER... (a) the absolute working directory path to set; (b) a relative path that will be applied to the current working directory. p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_VOL_NONE_EXIST FS_ERR_WORKING_DIR_NONE_AVAIL FS_ERR_WORKING_DIR_INVALID RETURNED VALUE, None. NOTES/WARNINGS None. 230 Working directory set. Argument path_dir passed a NULL pointer. No volumes exist. No working directories available. Argument path_dir passed an invalid directory. 600-uC-FS-001.book Page 231 Wednesday, October 10, 2012 12:03 PM A-2 POSIX API FUNCTIONS char * fs_asctime_r (const struct fs_tm *p_time, char *str_time); int fs_chdir (const char *path_dir); void fs_clearerr (FS_FILE *p_file); int fs_closedir (FS_DIR *p_dir); (const fs_time_t char *p_ts, *str_time); int fs_fclose (FS_FILE *p_file); int fs_feof (FS_FILE *p_file); int fs_ferror (FS_FILE *p_file); int fs_fflush (FS_FILE *p_file); (FS_FILE fs_fpos_t *p_file, *p_pos); (FS_FILE *p_file); (const char const char *name_full, *str_mode); char * fs_ctime_r int fs_fgetpos void fs_flockfile FS_FILE * fs_fopen 231 600-uC-FS-001.book Page 232 Wednesday, October 10, 2012 12:03 PM Appendix A fs_size_t fs_fread int fs_fseek int fs_fsetpos long int fs_ftell int fs_ftruncate (void fs_size_t fs_size_t FS_FILE *p_dest, size, nitems, *p_file); (FS_FILE long int int *p_file, offset, origin); (FS_FILE fs_fpos_t *p_file, *p_pos); (FS_FILE *p_file); (FS_FILE fs_off_t *p_file, size); int fs_ftrylockfile (FS_FILE *p_file); void fs_funlockfile (FS_FILE *p_file); fs_size_t fs_fwrite char * fs_getcwd (void fs_size_t fs_size_t FS_FILE *p_src, size, nitems, *p_file); (char fs_size_t *path_dir, size); struct fs_tm * fs_localtime_r (const fs_time_t struct fs_tm 232 *p_ts, *p_time); 600-uC-FS-001.book Page 233 Wednesday, October 10, 2012 12:03 PM int fs_mkdir (const char *name_full); fs_time_t fs_mktime (struct fs_tm *p_time); FS_DIR * fs_opendir (const char *name_full); int fs_readdir int fs_remove int fs_rename void fs_rewind int fs_setbuf int fs_setvbuf (FS_DIR struct fs_dirent struct fs_dirent *p_dir, *p_dir_entry, **pp_result); (const char *name_full); (const char const char *name_full_old, *name_full_new); (FS_FILE *p_file); (FS_FILE fs_size_t *p_file, size); (FS_FILE char int fs_size_t *p_file, *p_buf, mode, size); 233 600-uC-FS-001.book Page 234 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-1 fs_asctime_r() char *fs_asctime_r (const struct fs_tm *p_time, char *str_time); File Called from Code enabled by fs_api.c Application FS_CFG_API_EN Converts date/time to string in the form: Sun Sep 16 01:03:52 1973\n\0 ARGUMENTS p_time Pointer to date/time to format. str_time String buffer that will receive date/time string (see Note). RETURNED VALUE Pointer to str_time, if NO errors. Pointer to NULL, otherwise. NOTES/WARNINGS str_time MUST be at least 26 characters long. Buffer overruns MUST be prevented by caller. 234 600-uC-FS-001.book Page 235 Wednesday, October 10, 2012 12:03 PM A-2-2 fs_chdir() int fs_chdir (const char *path_dir); File Called from Code enabled by fs_api.c Application FS_CFG_API_EN and FS_CFG_WORKING_DIR_EN Set the working directory for the current task. ARGUMENTS path_dir String buffer that specifies EITHER... the absolute working directory path to set; relative path that will be applied to the current working directory. RETURNED VALUE 0, if no error occurs. -1, otherwise NOTES/WARNINGS None. 235 600-uC-FS-001.book Page 236 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-3 fs_clearerr() void fs_clearerr (FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Clear EOF and error indicators on a file. ARGUMENTS p_file Pointer to a file. RETURNED VALUE None. NOTES/WARNINGS None. 236 600-uC-FS-001.book Page 237 Wednesday, October 10, 2012 12:03 PM A-2-4 fs_closedir() int fs_closedir (FS_DIR *p_dir); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and FS_CFG _DIR_EN Close and free a directory. ARGUMENTS p_dir Pointer to a directory. RETURNED VALUE 0, if the directory is successfully closed. -1, if any error was encountered. NOTES/WARNINGS After a directory is closed, the application MUST desist from accessing its directory pointer. This could cause file system corruption, since this handle may be re-used for a different directory. 237 600-uC-FS-001.book Page 238 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-5 fs_ctime_r() char *fs_ctime_r (const fs_time_t *p_ts, char *str_time); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Converts timestamp to string in the form: Sun Sep 16 01:03:52 1973\n\0 ARGUMENTS p_ts Pointer to timestamp to format. str_time String buffer that will receive date/time string (see Note). RETURNED VALUE Pointer to str_time, if NO errors. Pointer to NULL, otherwise. NOTES/WARNINGS str_time MUST be at least 26 characters long. Buffer overruns MUST be prevented by caller. 238 600-uC-FS-001.book Page 239 Wednesday, October 10, 2012 12:03 PM A-2-6 fs_fclose() int fs_fclose (FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Close and free a file. ARGUMENTS p_file Pointer to a file. RETURNED VALUE 0, if the file was successfully closed. FS_EOF, otherwise. NOTES/WARNINGS After a file is closed, the application MUST desist from accessing its file pointer. This could cause file system corruption, since this handle may be re-used for a different file. If the most recent operation is output (write), all unwritten data is written to the file. Any buffer assigned with fs_setbuf() or fs_setvbuf() shall no longer be accessed by the file system and may be re-used by the application. 239 600-uC-FS-001.book Page 240 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-7 fs_feof() int fs_feof (FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Test EOF indicator on a file. ARGUMENTS p_file Pointer to a file. RETURNED VALUE 0, if EOF indicator is NOT set or if an error occurred Non-zero value, if EOF indicator is set. NOTES/WARNINGS The return value from this function should ALWAYS be tested against 0: rtn = fs_feof(p_file); if (rtn == 0) { // EOF indicator is NOT set } else { // EOF indicator is set } 240 If the end-of-file indicator is set (i.e., fs_feof() returns DEF_YES), fs_clearerr() can be used to clear that indicator. 600-uC-FS-001.book Page 241 Wednesday, October 10, 2012 12:03 PM A-2-8 fs_ferror() int fs_ferror (FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Test error indicator on a file. ARGUMENTS p_file Pointer to a file. RETURNED VALUE 0, if error indicator is NOT set or if an error occurred Non-zero value, if error indicator is set. NOTES/WARNINGS The return value from this function should ALWAYS be tested against 0: rtn = fs_ferror(p_file); if (rtn == 0) { // Error indicator is NOT set } else { // Error indicator is set } If the error indicator is set (i.e., fs_ferror() returns a non-zero value), fs_clearerr() can be used to clear that indicator. 241 600-uC-FS-001.book Page 242 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-9 fs_fflush() int fs_fflush (FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and FS_CF_FILE_BUF_EN Flush buffer contents to file. ARGUMENTS p_file Pointer to a file. RETURNED VALUE 0, if flushing succeeds. FS_EOF, otherwise. NOTES/WARNINGS If the most recent operation is output (write), all unwritten data is written to the file. If the most recent operation is input (read), all buffered data is cleared. 242 600-uC-FS-001.book Page 243 Wednesday, October 10, 2012 12:03 PM A-2-10 fs_fgetpos() int fs_fgetpos (FS_FILE *p_file, fs_fpos_t *p_pos); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Get file position indicator. ARGUMENTS p_file Pointer to a file. p_pos Pointer to variable that will receive the file position indicator. RETURNED VALUE 0, if no error occurs. Non-zero value, otherwise. NOTES/WARNINGS The return value should be tested against 0: rtn = fs_fgetpos(p_file, &pos); if (rtn == 0) { // No error occurred } else { // Handle error } The value placed in pos should be passed to FS_fsetpos() to reposition the file to its position at the time when this function was called. 243 600-uC-FS-001.book Page 244 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-11 fs_flockfile() void fs_flockfile (FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and FS_CFG_FILE_LOCK_EN Acquire task ownership of a file. ARGUMENTS p_file Pointer to a file. RETURNED VALUE None. NOTES/WARNINGS A lock count is associated with each file: The file is unlocked when the lock count is zero. If the lock count is positive, a task owns the file. When fs_flockfile() is called, if... ...the lock count is zero OR ...the lock count is positive and the caller owns the file... ...the lock count will be incremented and the caller will own the file. Otherwise, the caller will wait until the lock count returns to zero. Each call to fs_funlockfile() incremenets the lock count. Matching calls to fs_flockfile() (or fs_ftrylockfile()) and fs_funlockfile() can be nested. 244 600-uC-FS-001.book Page 245 Wednesday, October 10, 2012 12:03 PM A-2-12 fs_fopen() FS_FILE *fs_fopen (const char *name_full, const char *str_mode); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Open a file. ARGUMENTS name_full Name of the file. See section 4-3 "C/FS File and Directory Names and Paths" on page 62 for information about file names. str_mode Access mode of the file. RETURNED VALUE Pointer to a file, if NO errors. Pointer to NULL, otherwise. NOTES/WARNINGS The access mode should be one of the strings shown in section Table 6-2 "fopen() mode strings and mode equivalents" on page 86. The character `b' has no effect. Opening a file with read mode fails if the file does not exist. Opening a file with append mode causes all writes to be forced to the end-of-file. 245 600-uC-FS-001.book Page 246 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-13 fs_fread() fs_size_t fs_fread (void *p_dest, fs_size_t size, fs_size_t nitems, FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Read from a file. ARGUMENTS p_dest Pointer to destination buffer. size Size of each item to read. nitems Number of items to read. p_file Pointer to a file. RETURNED VALUE Number of items read. NOTES/WARNINGS The size or nitems is 0, then the file is unchanged and zero is returned. If the file is buffered and the last operation is output (write), then a call to fs_flush() or fs_fsetpos() or fs_fseek() MUST occur before input (read) can be performed. The file must have been opened in read or update (read/write) mode. 246 600-uC-FS-001.book Page 247 Wednesday, October 10, 2012 12:03 PM A-2-14 fs_fseek() int fs_fseek (FS_FILE *p_file, long int offset, int origin); File Called from Code enabled by fs_api..c Application; fs_frewind() FS_CFG_API_EN Set file position indicator. ARGUMENTS p_file Pointer to a file. offset Offset from the file position specified by whence. origin Reference position for offset: FS_SEEK_SET FS_SEEK_CUR FS_SEEK_END Offset is from the beginning of the file. Offset is from the current file position. Offset is from the end of the file. RETURNED VALUE 0, if the function succeeds. -1, otherwise. 247 600-uC-FS-001.book Page 248 Wednesday, October 10, 2012 12:03 PM Appendix A NOTES/WARNINGS If a read or write error occurs, the error indicator shall be set. The new file position, measured in bytes form the beginning of the file, is obtained by adding offset to...: ...0 (the beginning of the file), if whence is FS_SEEK_SET; ...the current file position, if whence is FS_SEEK_CUR; ...the file size, if whence is FS_SEEK_END; The end-of-file indicator is cleared. If the file position indicator is set beyond the file's current data... 248 ...and data is later written to that point, reads from the gap will read 0. ...the file MUST be opened in write or read/write mode. 600-uC-FS-001.book Page 249 Wednesday, October 10, 2012 12:03 PM A-2-15 fs_fsetpos() int fs_fsetpos (FS_FILE *p_file, fs_fpos_t *p_pos); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Set file position indicator. ARGUMENTS p_file Pointer to a file. p_pos Pointer to variable containing file position indicator. RETURNED VALUE 0, if the function succeeds. Non-zero value, otherwise. NOTES/WARNINGS The return value should be tested against 0: rtn = fs_fsetpos(pfile, &pos); if (rtn == 0) { // No error occurred } else { // Handle error } If a read or write error occurs, the error indicator shall be set. The value stored in pos should be the value from an earlier call to fs_fgetpos(). No attempt is made to verify that the value in pos was obtained by a call to fs_fgetpos(). See also fs_fseek(). 249 600-uC-FS-001.book Page 250 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-16 fs_ftell() long int fs_ftell (FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Get file position indicator. ARGUMENTS p_file Pointer to a file. RETURNED VALUE The current file system position, if the function succeeds. -1, otherwise. NOTES/WARNINGS The file position returned is measured in bytes from the beginning of the file. 250 600-uC-FS-001.book Page 251 Wednesday, October 10, 2012 12:03 PM A-2-17 fs_ftruncate() int fs_ftruncate (FS_FILE *p_file, fs_off_t size); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and not FS_CFG_RD_ONLY_EN Truncate a file. ARGUMENTS p_file Pointer to a file. size Size of the file after truncation RETURNED VALUE 0, if the function succeeds. -1, otherwise. NOTES/WARNINGS The file MUST be opened in write or read/write mode. If fs_ftruncate() succeeds, the size of the file shall be equal to length. If the size of the file was previously greater than length, the extra data shall no longer be available. If the file previously was smaller than this length, the size of the file shall be increased. If the file position indicator before the call to fs_ftruncate() lay in the extra data destroyed by the function, then the file position will be set to the end-of-file. 251 600-uC-FS-001.book Page 252 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-18 fs_ftrylockfile() int fs_ftrylockfile (FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and FS_CFG_FILE_LOCK_EN Acquire task ownership of a file (if available). ARGUMENTS p_file Pointer to a file. RETURNED VALUE 0, if no error occurs and the file lock is acquired. Non-zero value, otherwise. NOTES/WARNINGS fs_ftrylockfile() is the non-blocking version of fs_flockfile(); if the lock is not available, the function returns an error. See fs_flockfile(). 252 600-uC-FS-001.book Page 253 Wednesday, October 10, 2012 12:03 PM A-2-19 fs_funlockfile() void fs_funlockfile (FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and FS_CFG_FILE_LOCK_EN Release task ownership of a file. ARGUMENTS p_file Pointer to a file. RETURNED VALUE None. NOTES/WARNINGS See fs_flockfile(). 253 600-uC-FS-001.book Page 254 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-20 fs_fwrite() fs_size_t fs_fwrite (void *p_src, fs_size_t size, fs_size_t nitems, FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and not FS_CFG_RD_ONLY_EN Write to a file. ARGUMENTS p_src Pointer to source buffer. size Size of each item to write. nitems Number of items to write. p_file Pointer to a file. RETURNED VALUE Number of items written. NOTES/WARNINGS The size or nitems is 0, then the file is unchanged and zero is returned. If the file is buffered and the last operation is input (read), then a call to fs_fsetpos() or fs_fseek() MUST occur before output (write can be performed unless the end-of-file was encountered. The file must have been opened in write or update (read/write) mode. If the file was opened in append mode, all writes are forced to the end-of-file. 254 600-uC-FS-001.book Page 255 Wednesday, October 10, 2012 12:03 PM A-2-21 fs_getcwd() char *fs_getcwd (char *path_dir, fs_size_t size) File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and not FS_CFG_WORKING_DIR_EN Get the working directory for the current task. ARGUMENTS path_dir String buffer that will receive the working directory path. size Size of string buffer. RETURNED VALUE Pointer to path_dir, if no error occurs. Pointer to NULL, otherwise NOTES/WARNINGS None. 255 600-uC-FS-001.book Page 256 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-22 fs_localtime_r() struct fs_tm *fs_localtime_r (const fs_time_t struct fs_tm *p_ts, *p_time); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Convert timestamp to date/time. ARGUMENTS p_ts Pointer to time value. p_time Pointer to variable that will receive broken-down time. RETURNED VALUE Pointer to p_time, if NO errors. Pointer to NULL, otherwise. NOTES/WARNINGS None. 256 600-uC-FS-001.book Page 257 Wednesday, October 10, 2012 12:03 PM A-2-23 fs_mkdir() int fs_mkdir (const char *name_full); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and not FS_CFG_RD_ONLY_EN Create a directory. ARGUMENTS name_full Name of the directory. RETURNED VALUE 0, if the directory is created. -1, if the directory is NOT created. NOTES/WARNINGS None. EXAMPLE void App_Fnct (void) { int err; . . . err = fs_mkdir("sd:0:\\data\\old"); /* Make dir. */ if (err != 0) { APP_TRACE_INFO(("Could not make dir.")); } . . . } 257 600-uC-FS-001.book Page 258 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-24 fs_mktime() fs_time_t fs_mktime (struct fs_tm *p_time); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Convert date/time to timestamp. ARGUMENTS p_time Pointer to date/time to convert. RETURNED VALUE Time value, if NO errors. (fs_time_t)-1, otherwise. NOTES/WARNINGS None. 258 600-uC-FS-001.book Page 259 Wednesday, October 10, 2012 12:03 PM A-2-25 fs_opendir() FS_DIR *fs_opendir (const char *name_full); D File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and FS_CFG_DIR_EN Open a directory. ARGUMENTS name_full Name of the directory. See section 4-3 "C/FS File and Directory Names and Paths" on page 62 for information about directory names. RETURNED VALUE Pointer to a directory, if NO errors. Pointer to NULL, otherwise. NOTES/WARNINGS None. 259 600-uC-FS-001.book Page 260 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-26 fs_readdir_r() int fs_readdir (FS_DIR *p_dir, struct fs_dirent *p_dir_entry, struct fs_dirent **pp_result); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and FS_CFG_DIR_EN Read a directory entry from a directory. ARGUMENTS p_dir Pointer to a directory. p_dir_entry pp_result Pointer to variable that will receive directory entry information. Pointer to variable that will receive: p_dir_entry, if NO error occurs AND directory does not encounter EOF. pointer to NULL if an error occurs OR directory encounters EOF. RETURNED VALUE 1, if an error occurs. 0, otherwise. NOTES/WARNINGS Entries for "dot" (current directory) and "dot-dot" (parent directory) shall be returned, if present. No entry with an empty name shall be returned. If an entry is removed from or added to the directory after the directory has been opened, information may or may not be returned for that entry. 260 600-uC-FS-001.book Page 261 Wednesday, October 10, 2012 12:03 PM A-2-27 fs_remove() int fs_remove (const char *name_full); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and not FS_CFG_RD_ONLY_EN Delete a file or directory. ARGUMENTS name_full Name of the entry. RETURNED VALUE 0, if the file is NOT removed. -1, if the file is NOT removed. NOTES/WARNINGS When a file is removed, the space occupied by the file is freed and shall no longer be accessible. A directory can be removed only if it is an empty directory. The root directory cannot be removed. 261 600-uC-FS-001.book Page 262 Wednesday, October 10, 2012 12:03 PM Appendix A EXAMPLE void App_Fnct (void) { int err; . . . err = fs_remove("sd:0:\\data\\file001.txt"); /* Remove file. if (err != 0) { APP_TRACE_INFO(("Could not remove file.")); } . . . err = fs_remove("sd:0:\\data\\old"); /* Remove dir. if (err != 0) { APP_TRACE_INFO(("Could not remove dir.")); } . . . } 262 */ */ 600-uC-FS-001.book Page 263 Wednesday, October 10, 2012 12:03 PM A-2-28 fs_rename() int fs_rename (const char *name_full_old, const char *name_full_new); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN and not FS_CFG_RD_ONLY_EN Rename a file or directory. ARGUMENTS name_full_old Old name of the entry. name_full_new New name of the entry. RETURNED VALUE 0, if the entry is NOT renamed. -1, if the entry is NOT renamed. NOTES/WARNINGS name_full_old and name_full_new MUST specify entries on the same volume. If path_old and path_new specify the same entry, the volume will not be modified and no error will be returned. If path_old specifies a file: path_new must NOT specify a directory; if path_new is a file, it will be removed. If path_old specifies a directory: path_new must NOT specify a file 263 600-uC-FS-001.book Page 264 Wednesday, October 10, 2012 12:03 PM Appendix A if path_new is a directory, path_new MUST be empty; if so, it will be removed. The root directory may NOT be renamed. EXAMPLE void App_Fnct (void) { int err; . . . /* See Note #1. err = fs_rename("sd:0:\\data\\file001.txt", /* Rename file. "sd:0:\\data\\old\\file001.txt"); if (err != 0) { APP_TRACE_INFO(("Could not rename file.")); } . . . */ */ } L4-6(1) For this example file rename to succeed, the following must be true when the function is called: The file sd:0:\data\file001.txt must exist. The directory sd:0:\data\old must exist. If sd:0:\data\old\file001.txt exists, it must not be read-only. If sd:0:\data\old\file001.txt exists and is not read-only, it will be removed and sd:0:\data\file001.txt will be renamed. 264 600-uC-FS-001.book Page 265 Wednesday, October 10, 2012 12:03 PM A-2-29 fs_rewind() void fs_rewind (FS_FILE *p_file); File Called from Code enabled by fs_api..c Application FS_CFG_API_EN Reset file position indicator of a file. ARGUMENTS p_file Pointer to a file. RETURNED VALUE None. NOTES/WARNINGS fs_rewind() is equivalent to (void)fs_fseek(p_file, 0, FS_SEEK_SET) except that it also clears the error indictor of the file. 265 600-uC-FS-001.book Page 266 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-30 fs_rmdir() int fs_rmdir (const char *name_full); File Called from Code enabled by fs_api.c Application FS_CFG_API_EN and not FS_CFG_RD_ONLY_EN Delete a directory. ARGUMENTS name_full Name of the file. RETURNED VALUE 0, if the directory is removed. -1, if the directory is NOT removed. NOTES/WARNINGS A directory can be removed only if it is an empty directory. The root directory cannot be removed. EXAMPLE void App_Fnct (void) { int err; . . . err = fs_rmdir("sd:0:\\data\\old"); /* Remove dir. if (err != 0) { APP_TRACE_INFO(("Could not remove dir.")); } . . . } 266 */ 600-uC-FS-001.book Page 267 Wednesday, October 10, 2012 12:03 PM A-2-31 fs_setbuf() int fs_setbuf (FS_FILE char *p_file, *p_buf); File Called from Code enabled by fs_api.c Application FS_CFG_API_EN and FS_CFG_FILE_BUF_EN Assign buffer to a file. ARGUMENTS p_file Pointer to a file. p_buf Pointer to a buffer of FS_BUFSIZ bytes. RETURNED VALUE -1, if an error occurs. 0, if no error occurs. NOTES/WARNINGS fs_setbuf() is equivalent to fs_setvbuf() invoked with FS__IOFBF for mode and FS_BUFSIZE for size. 267 600-uC-FS-001.book Page 268 Wednesday, October 10, 2012 12:03 PM Appendix A A-2-32 fs_setvbuf() int fs_setvbuf (FS_FILE *p_file, char *p_buf, int mode, fs_size_t size); File Called from Code enabled by fs_api.c Application FS_CFG_API_EN and FS_CFG_FILE_BUF_EN Assign buffer to a file. ARGUMENTS p_file Pointer to a file. p_buf Pointer to buffer. mode Buffer mode: FS__IONBR FS__IOFBF size RETURNED VALUE -1, if an error occurs. 0, if no error occurs. 268 Unbuffered. Fully buffered. Size of buffer, in octets. 600-uC-FS-001.book Page 269 Wednesday, October 10, 2012 12:03 PM NOTES/WARNINGS fs_setvbuf() MUST be used after a stream is opened but before any other operation is performed on stream. size MUST be more than or equal to the size of one sector; it will be rounded DOWN to the nearest size of a multiple of full sectors. Once a buffer is assigned to a file, a new buffer may not be assigned nor may the assigned buffer be removed. To change the buffer, the file should be closed and re-opened. Upon power loss, any data stored in file buffers will be lost. 269 600-uC-FS-001.book Page 270 Wednesday, October 10, 2012 12:03 PM Appendix A A-3 DEVICE FUNCTIONS Most device access functions can return any of the following device errors: FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV FS_ERR_DEV_IO FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_TIMEOUT Device Device Device Device Device Device needs to be low-level formatted. access error. I/O error. is not open. is not present. timeout error. Each of these indicates that the state of the device is not suitable for the intended operation. void FSDev_AccessLock (CPU_CHAR CPU_INT32U FS_ERR *name_dev, timeout, *p_err); (CPU_CHAR FS_ERR *name_dev, *p_err); (CPU_CHAR FS_ERR *name_dev, *p_err); FS_PARTITION_NBR FSDev_GetNbrPartitions (CPU_CHAR FS_ERR *name_dev, *p_err); void FSDev_AccessUnlock void FSDev_Close void FSDev_GetDevName (FS_QTY CPU_CHAR FS_QTY FSDev_GetDevCnt (void); FS_QTY FSDev_GetDevCntMax (void); 270 dev_nbr, *name_dev); 600-uC-FS-001.book Page 271 Wednesday, October 10, 2012 12:03 PM void FSDev_Invalidate void FSDev_Open FS_PARTITION_NBR FSDev_PartitionAdd void FSDev_PartitionFind void FSDev_PartitionInit void FSDev_Query void FSDev_Rd CPU_BOOLEAN FSDev_Refresh (CPU_CHAR FS_ERR *name_dev, *p_err); (CPU_CHAR void FS_ERR *name_dev, *p_dev_cfg, *p_err); (CPU_CHAR FS_SEC_QTY FS_ERR *name_dev, partition_size, *p_err); (CPU_CHAR FS_PARTITION_NBR FS_PARTITION_ENTRY FS_ERR *name_dev, partition_nbr, *p_partition_entry, *p_err); (CPU_CHAR FS_SEC_QTY FS_ERR *name_dev, partition_size, *p_err); (CPU_CHAR FS_DEV_INFO FS_ERR *name_dev, *p_info, *p_err); (CPU_CHAR void FS_SEC_NBR FS_SEC_QTY FS_ERR *name_dev, *p_dest, start, cnt, *p_err); (CPU_CHAR FS_ERR *name_dev, *p_err); 271 600-uC-FS-001.book Page 272 Wednesday, October 10, 2012 12:03 PM Appendix A void FSDev_Wr 272 (CPU_CHAR void FS_SEC_NBR FS_SEC_QTY FS_ERR *name_dev, *p_src, start, cnt, *p_err); 600-uC-FS-001.book Page 273 Wednesday, October 10, 2012 12:03 PM A-3-1 FSDev_AccessLock() void FSDev_AccessLock (CPU_CHAR *name_dev, CPU_INT32U timeout FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application N/A Acquire exclusive access to a device. See also section 5-4 "Raw Device IO" on page 72. ARGUMENTS name_dev Device name. timeout Time to wait for a lock in milliseconds. p_err Pointer to variable that will receive return error code from this function : FS_ERR_NONE FS_ERR_DEV_NOT_OPEN FS_ERR_NAME_NULL FS_ERR_OS_LOCK FS_ERR_OS_LOCK_TIMEOUT Device removed successfully. Device is not open. Argument name_dev passed a NULL pointer Error acquiring device access lock. Time-out waiting for device access lock. RETURNED VALUE None. NOTES/WARNINGS None. 273 600-uC-FS-001.book Page 274 Wednesday, October 10, 2012 12:03 PM Appendix A A-3-2 FSDev_AccessUnlock() void FSDev_AccessUnlock (CPU_CHAR FS_ERR *name_dev, *p_err); File Called from Code enabled by fs_dev.c Application N/A Release exclusive access to a device. See also section 5-4 "Raw Device IO" on page 72. ARGUMENTS name_dev Device name. p_err Pointer to variable that will receive return error code from this function : FS_ERR_NONE FS_ERR_DEV_NOT_OPEN FS_ERR_NAME_NULL RETURNED VALUE None. NOTES/WARNINGS None. 274 Device removed successfully. Device is not open. Argument name_dev passed a NULL pointer 600-uC-FS-001.book Page 275 Wednesday, October 10, 2012 12:03 PM A-3-3 FSDev_Close() void FSDev_Close (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application N/A Close and free a device. ARGUMENTS name_dev Device name. p_err Pointer to variable that will receive return error code from this function : FS_ERR_NONE FS_ERR_DEV_NOT_OPEN FS_ERR_NAME_NULL Device removed successfully. Device is not open. Argument name_dev passed a NULL pointer RETURNED VALUE None. NOTES/WARNINGS None. 275 600-uC-FS-001.book Page 276 Wednesday, October 10, 2012 12:03 PM Appendix A A-3-4 FSDev_GetDevName() void FSDev_GetDevName (FS_QTY dev_nbr, CPU_CHAR *name_dev); File Called from Code enabled by fs_dev.c Application N/A Get name of the nth open device. dev_nbr should be between 0 and the return value of FSDev_GetNbrDevs() (inclusive). ARGUMENTS dev_nbr Device number. name_dev String buffer that will receive the device name (see Note #2). RETURNED VALUE None. NOTES/WARNINGS name_dev must point to a character array of FS_CFG_MAX_DEV_NAME_LEN characters. If the device does not exist, name_dev will receive an empty string. 276 600-uC-FS-001.book Page 277 Wednesday, October 10, 2012 12:03 PM A-3-5 FSDev_GetDevCnt() FS_QTY FSDev_GetDevCnt (void); File Called from Code enabled by fs_dev.c Application N/A Gets the number of open devices. ARGUMENTS None. RETURNED VALUE Number of devices currently open. NOTES/WARNINGS None. 277 600-uC-FS-001.book Page 278 Wednesday, October 10, 2012 12:03 PM Appendix A A-3-6 FSDev_GetDevCntMax() FS_QTY FSDev_GetDevCntMax (void); File Called from Code enabled by fs_dev.c Application N/A Gets the maximum possible number of open devices. ARGUMENTS None. RETURNED VALUE Maximum number of open devices. NOTES/WARNINGS None. 278 600-uC-FS-001.book Page 279 Wednesday, October 10, 2012 12:03 PM A-3-7 FSDev_GetNbrPartitions() FS_PARTITION_NBR FSDev_GetNbrPartitions (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application FS_CFG_PARTITION_EN Get number of partitions on a device ARGUMENTS name_dev Pointer to the device name. p_err Pointer to variable that will receive return error code from this function. FS_ERR_NONE FS_ERR_DEV_VOL_OPEN FS_ERR_INVALID_SIG FS_ERR_NAME_NULL Number of partitions obtained. Volume open on device. Invalid MBR signature. Argument name_dev passed a NULL pointer. Or device access error (see section B-4 "Device Error Codes" on page 394). RETURNED VALUE Number of partitions on the device, if no error was encountered. Zero, otherwise. NOTES/WARNINGS Device state change will result from device I/O, not present or timeout error. 279 600-uC-FS-001.book Page 280 Wednesday, October 10, 2012 12:03 PM Appendix A A-3-8 FSDev_Invalidate() void FSDev_Invalidate (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application N/A Invalidate files and volumes opened on a device. See also section 5-4 "Raw Device IO" on page 72. ARGUMENTS name_dev Device name p_err Pointer to variable that will receive return error code from this function. FS_ERR_NONE FS_ERR_NAME_NULL Partition added. Argument name_dev passed a NULL pointer. Or device access error (see section B-4 "Device Error Codes" on page 394). RETURNED VALUE None. NOTES/WARNINGS 1 Operations on an affected file or volume will fail with an FS_ERR_DEV_CHNGD error. 2 Invalidation will happen automatically following a removable media change. 280 600-uC-FS-001.book Page 281 Wednesday, October 10, 2012 12:03 PM A-3-9 FSDev_Open() void FSDev_Open (CPU_CHAR *name_dev, void *p_dev_cfg, FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application N/A Open a device. ARGUMENTS name_dev Device name. See section 4-3 "C/FS File and Directory Names and Paths" on page 62 for information about device names. p_dev_cfg Pointer to device configuration. p_err Pointer to variable that will receive the return error code from this function (see Note #2): FS_ERR_NONE FS_ERR_DEV_ALREADY_OPEN FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_INVALID_NAME FS_ERR_DEV_INVALID_SEC_SIZE FS_ERR_DEV_INVALID_SIZE FS_ERR_DEV_INVALID_UNIT_NBR FS_ERR_DEV_IO FS_ERR_DEV_NONE_AVAIL FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_TIMEOUT FS_ERR_DEV_UNKNOWN FS_ERR_NAME_NULL Device opened successfully. Device is already open. Device needs to be low-level formatted. Specified device name not valid. Invalid device sector size. Invalid device size. Specified unit number invalid. Device I/O error. No devices available. Device is not present. Device timeout error. Unknown device error. Argument name_dev passed a NULL pointer RETURNED VALUE None. 281 600-uC-FS-001.book Page 282 Wednesday, October 10, 2012 12:03 PM Appendix A NOTES/WARNINGS The return error code from the function SHOULD always be checked by the calling application to determine whether the device was successfully opened. Repeated calls to FSDev_Open() resulting in errors that do not indicate failure to open (such as FS_ERR_DEV_LOW_FMT_INVALID) without matching FSDev_Close() calls may exhaust the supply of device structures. If FS_ERR_NONE is returned, then the device has been added to the file system and is immediately accessible. If FS_DEV_INVALID_LOW_FMT is returned, then the device has been added to the file system, but needs to be low-level formatted, though it is present. If FS_ERR_DEV_NOT_PRESENT, FS_ERR_DEV_IO or FS_ERR_DEV_TIMEOUT is returned, then the device has been added to the file system, though it is probably not present. The device will need to be either closed and re-added, or refreshed. If any of the follwing is retutrned: FS_ERR_DEV_INVALID_NAME FS_ERR_DEV_INVALID_SEC_SIZE FS_ERR_DEV_INVALID_SIZE FS_ERR_DEV_INVALID_UNIT_NBR FS_ERR_DEV_NONE_AVAIL ...then the device has NOT been added to the file system. 282 If FS_ERR_DEV_UNKNOWN is returned, then the device driver is in an indeterminate state. The system MAY need to be restarted and the device driver should be examined for errors. The device has NOT been added to the file system. 600-uC-FS-001.book Page 283 Wednesday, October 10, 2012 12:03 PM A-3-10 FSDev_PartitionAdd() FS_PARTITION_NBR FSDev_PartitionAdd (CPU_CHAR *name_dev, FS_SEC_QTY partition_size, FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application FS_CFG_PARTITION_EN and not FS_CFG_RD_ONLY_EN Adds a partition to a device. See also section 5-5 "Partitions" on page 73. ARGUMENTS name_dev Device name partition_size p_err Size, in sectors, of the partition to add. Pointer to variable that will receive return error code from this function. FS_ERR_NONE FS_ERR_INVALID_PARTITION FS_ERR_INVALID_SEC_NBR FS_ERR_INVALID_SIG FS_ERR_NAME_NULL Partition added. Invalid partition. Sector start or count invalid. Invalid MBR signature. Argument name_dev passed a NULL pointer. Or device access error (see section B-4 "Device Error Codes" on page 394). RETURNED VALUE The index of the created partition. The first partition on the device has an index of 0. FS_INVALID_PARTITION_NBR is returned if the function fails to add the partition. NOTES/WARNINGS Device state change will result from device I/O, not present or timeout error. 283 600-uC-FS-001.book Page 284 Wednesday, October 10, 2012 12:03 PM Appendix A A-3-11 FSDev_PartitionFind() void FSDev_PartitionFind (CPU_CHAR *name_dev, FS_PARTITION_NBR partition_nbr, FS_PARTITION_ENTRY *p_partition_entry, FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application FS_CFG_PARTITION_EN Find a partition on a device. See also section 5-5 "Partitions" on page 73. ARGUMENTS name_dev Device name. partition_nbr Index of the partition to find. p_partition_entry Pointer to variable that will receive the partition information. p_err Pointer to variable that will receive return error code from this function. FS_ERR_NONE FS_ERR_DEV_VOL_OPEN FS_ERR_INVALID_PARTITION FS_ERR_INVALID_SEC_NBR FS_ERR_INVALID_SIG FS_ERR_NAME_NULL FS_ERR_NULL_PTR Partition found. Volume open on device. Invalid partition. Sector start or count invalid. Invalid MBR signature. Argument name_dev passed a NULL pointer. Argument p_partition_entry passed a NULL pointer. Or device access error (see section B-4 "Device Error Codes" on page 394). 284 600-uC-FS-001.book Page 285 Wednesday, October 10, 2012 12:03 PM RETURNED VALUE None. NOTES/WARNINGS Device state change will result from device I/O, not present or timeout error. 285 600-uC-FS-001.book Page 286 Wednesday, October 10, 2012 12:03 PM Appendix A A-3-12 FSDev_PartitionInit() void FSDev_PartitionInit (CPU_CHAR *name_dev, FS_SEC_QTY partition_size, FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application not FS_CFG_RD_ONLY_EN Initialize the partition structure on a device. See also section 5-5 "Partitions" on page 73. ARGUMENTS name_dev Device name. partition_size Size of partition, in sectors. OR 0, if partition will occupy entire device. p_err Pointer to variable that will receive the return error code from this function. FS_ERR_NONE FS_ERR_DEV_VOL_OPEN FS_ERR_INVALID_SEC_NBR FS_ERR_NAME_NULL Partition structure initialized. Volume open on device. Sector start or count invalid. Argument name_dev passed a NULL pointer. Or device access error (see section B-4 "Device Error Codes" on page 394). RETURNED VALUE None. NOTES/WARNINGS 1 Function blocked if a volume is open on the device. All volume (and files) must be closed prior to initializing the partition structure, since it will obliterate any existing file system. 2 Device state change will result from device I/O, not present or timeout error. 286 600-uC-FS-001.book Page 287 Wednesday, October 10, 2012 12:03 PM A-3-13 FSDev_Query() void FSDev_Query (CPU_CHAR *name_dev, FS_DEV_INFO *p_info, FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application N/A Obtain information about a device. ARGUMENTS name_dev Device name. p_info Pointer to structure that will receive device information (see Note). p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NULL_PTR FS_ERR_INVALID_SEC_NBR Device information obtained. Argument name_dev passed a NULL pointer. Argument p_info passed a NULL pointer. Sector start or count invalid. Or device access error (see section B-4 "Device Error Codes" on page 394). RETURNED VALUE None. NOTES/WARNINGS For removable medias, FSDev_Query() will return a valid value for the State and Fixed members of p_info even if the media is not present, Size and SecSize will be set to 0. In such cases an error will be returned stating the reason why the device was unaccessible. Otherwise, if a fatal error occurs or the device is not opened an appropriate error will be return and the content of p_info will be invalid. 287 600-uC-FS-001.book Page 288 Wednesday, October 10, 2012 12:03 PM Appendix A A-3-14 FSDev_Rd() void FSDev_Rd (CPU_CHAR *name_dev, void *p_dest, FS_SEC_NBR start,D FS_SEC_QTY cnt, FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application N/A Read data from device sector(s). See also section 5-4 "Raw Device IO" on page 72. ARGUMENTS name_dev Device name. p_dest Pointer to destination buffer. start Start sector of read. cnt Number of sectors to read p_err Pointer to variable that will receive the return error code from this function FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NULL_PTR Sector(s) read. Argument name_dev passed a NULL pointer. Argument p_dest passed a NULL pointer. Or device access error (see section B-4 "Device Error Codes" on page 394). RETURNED VALUE None. NOTES/WARNINGS Device state change will result from device I/O, not present or timeout error. 288 600-uC-FS-001.book Page 289 Wednesday, October 10, 2012 12:03 PM A-3-15 FSDev_Refresh() CPU_BOOLEAN FSDev_Refresh (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application N/A Refresh a device.Arguments name_dev Device name. p_err Pointer to variable that will receive the return error code from this function. FS_ERR_NONE FS_ERR_DEV_INVALID_SEC_SIZE FS_ERR_DEV_INVALID_SIZE FS_ERR_DEV_INVALID_UNIT_NBR FS_ERR_NAME_NULL Device opened successfully. Invalid device sector size. Invalid device size. Specified unit number invalid. Argument name_dev passed a NULL pointer Or device access error (see section B-4 "Device Error Codes" on page 394). RETURNED VALUE DEF_YES, if the device has not changed. DEF_NO, if the device has not changed. NOTES/WARNINGS If device has changed, all volumes open on the device must be refreshed and all files closed and reopened. A device status change may be caused by A device was connected, but no longer is. A device was not connected, but now is. 289 600-uC-FS-001.book Page 290 Wednesday, October 10, 2012 12:03 PM Appendix A 290 A different device is connected. 600-uC-FS-001.book Page 291 Wednesday, October 10, 2012 12:03 PM A-3-16 FSDev_Wr() void FSDev_Wr (CPU_CHAR *name_dev, void *p_src, FS_SEC_NBR start, FS_SEC_QTY cnt, FS_ERR *p_err); File Called from Code enabled by fs_dev.c Application not FS_CFG_RD_ONLY_EN Write data to device sector(s). See also section 5-4 "Raw Device IO" on page 72. ARGUMENTS name_dev Device name. p_src Pointer to source buffer. start Start sector of write. cnt Number of sectors to write p_err Pointer to variable that will receive the return error code from this function FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NULL_PTR Sector(s) written. Argument name_dev passed a NULL pointer. Argument p_src passed a NULL pointer. Or device access error (see section B-4 "Device Error Codes" on page 394). RETURNED VALUE None. NOTES/WARNINGS Device state change will result from device I/O, not present or timeout error. 291 600-uC-FS-001.book Page 292 Wednesday, October 10, 2012 12:03 PM Appendix A A-4 DIRECTORY ACCESS FUNCTIONS void FSDir_Close (FS_DIR FS_ERR CPU_BOOLEAN FSDir_IsOpen (CPU_CHAR FS_ERR FS_DIR * FSDir_Open void FSDir_Rd 292 (CPU_CHAR FS_ERR *p_dir, *p_err); *name_full, *p_err); *name_full, *p_err); (FS_DIR *p_dir, FS_DIR_ENTRY *p_dir_entry, FS_ERR *p_err); 600-uC-FS-001.book Page 293 Wednesday, October 10, 2012 12:03 PM A-4-1 FSDir_Close() void FSDir_Close (FS_DIR *p_dir, FS_ERR *p_err); File Called from Code enabled by fs_dir.c Application; FS_CFG_DIR_EN fs_closedir() Close and free a directory. See fs_closedir() for more information. ARGUMENTS p_dir Pointer to a directory. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_DIR_DIS FS_ERR_DIR_NOT_OPEN Directory closed. Argument p_dir passed a NULL pointer. Argument p_dir's TYPE is invalid or unknown. Directory module disabled. Directory NOT open. RETURNED VALUE None. NOTES/WARNINGS None. 293 600-uC-FS-001.book Page 294 Wednesday, October 10, 2012 12:03 PM Appendix A A-4-2 FSDir_IsOpen() CPU_BOOLEAN FSDir_Open (CPU_CHAR *name_full, FS_ERR *p_err); File Called from Code enabled by fs_dir.c Application; FS_CFG_DIR_EN fs_opendir(); FSEntry_* Test if a directory is already open. This function is also called by various FSEntry_* functions to prevent concurrent access to an entry in the FAT filesystem. ARGUMENTS name_full Name of the directory. See section 4-3 "C/FS File and Directory Names and Paths" on page 62. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NAME_INVALID Directory opened. Argument name_full passed a NULL pointer. Entry name specified invalid or volume could not be found. Or entry error (see section B-8 "Entry Error Codes" on page 395). RETURNED VALUE DEF_NO, if dir is NOT open. DEF_YES, if dir is open. NOTES/WARNINGS None. 294 600-uC-FS-001.book Page 295 Wednesday, October 10, 2012 12:03 PM A-4-3 FSDir_Open() FS_DIR *FSDir_Open (CPU_CHAR *name_full, FS_ERR *p_err); File Called from Code enabled by fs_dir.c Application; FS_CFG_DIR_EN fs_opendir() Open a directory. See fs_opendir() for more information. ARGUMENTS name_full Name of the directory. See section 4-3 "C/FS File and Directory Names and Paths" on page 62. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DIR_DIS FS_ERR_DIR_NONE_AVAIL FS_ERR_DEV FS_ERR_NAME_INVALID FS_ERR_NAME_PATH_TOO_LONG FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED FS_ERR_BUF_NONE_AVAIL Directory opened. Argument name_full passed a NULL pointer. Directory module disabled. No directory available. Device access error. Entry name specified invalid or volume could not be found. Entry name is too long. Volume not opened. Volume not mounted. Buffer not available. Or entry error (see section B-8 "Entry Error Codes" on page 395). RETURNED VALUE Pointer to a directory, if NO errors. Pointer to NULL, otherwise. NOTES/WARNINGS None. 295 600-uC-FS-001.book Page 296 Wednesday, October 10, 2012 12:03 PM Appendix A A-4-4 FSDir_Rd() void FSDir_Rd (FS_DIR *p_dir, FS_DIR_ENTRY *p_dir_entry, FS_ERR *p_err); File Called from Code enabled by fs_dir.c Application; fs_readdir_r() FS_CFG_DIR_EN Read a directory entry from a directory. See fs_readdir_r() for more information. ARGUMENTS p_dir Pointer to a directory. p_dir_entry p_err Pointer to variable that will receive directory entry information. Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_DIR_DIS FS_ERR_DIR_NOT_OPEN FS_ERR_EOF FS_ERR_DEV FS_ERR_BUF_NONE_AVAIL RETURNED VALUE None. NOTES/WARNINGS None. 296 Directory read successfully. Argument p_dir/p_dir_entry passed a NULL pointer. Argument p_dir's TYPE is invalid or unknown. Directory module disabled. Directory NOT open. End of directory reached. Device access error. Buffer not available. 600-uC-FS-001.book Page 297 Wednesday, October 10, 2012 12:03 PM A-5 ENTRY ACCESS FUNCTIONS void FSEntry_AttribSet (CPU_CHAR FS_FLAGS FS_ERR void FSEntry_Copy void FSEntry_Create void FSEntry_Del void FSEntry_Query void FSEntry_Rename void FSEntry_TimeSet *name_full, attrib, *p_err); (CPU_CHAR CPU_CHAR CPU_BOOLEAN FS_ERR *name_full_src, *name_full_dest, excl, *p_err); (CPU_CHAR FS_FLAGS CPU_BOOLEAN FS_ERR *name_full, entry_type, excl, *p_err); (CPU_CHAR FS_FLAGS FS_ERR *name_full, entry_type, *p_err); (CPU_CHAR *name_full, FS_ENTRY_INFO *p_info, FS_ERR *p_err); (CPU_CHAR CPU_CHAR CPU_BOOLEAN FS_ERR *name_full_src, *name_full_dest, excl, *p_err); (CPU_CHAR FS_DATE_TIME CPU_INT08U FS_ERR *name_full, *p_time, flag, *p_err); 297 600-uC-FS-001.book Page 298 Wednesday, October 10, 2012 12:03 PM Appendix A A-5-1 FSEntry_AttribSet() void FSEntry_AttribSet (CPU_CHAR *name_full, FS_FLAGS attrib, FS_ERR *p_err); File Called from Code enabled by fs_entry.c Application not FS_CFG_RD_ONLY_EN Set a file or directory's attributes. ARGUMENTS name_full Name of the entry. See section 4-3 "C/FS File and Directory Names and Paths" on page 62. attrib Entry attributes to set (see Note #2). p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NAME_INVALID FS_ERR_NAME_PATH_TOO_LONG FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED FS_ERR_BUF_NONE_AVAIL FS_ERR_DEV Entry attributes set successfully. Argument name_full passed a NULL pointer. Entry name specified invalid OR volume could not be found. Entry name specified too long. Volume was not open. Volume was not mounted. Buffer not available. Device access error. Or entry error (See section B-8 "Entry Error Codes" on page 395). RETURNED VALUE None. 298 600-uC-FS-001.book Page 299 Wednesday, October 10, 2012 12:03 PM NOTES/WARNINGS If the entry does not exist, an error is returned. Three attributes may be modified by this function: FS_ENTRY_ATTRIB_RD FS_ENTRY_ATTRIB_WR FS_ENTRY_ATTRIB_HIDDEN Entry is readable. Entry is writable. Entry is hidden from user-level processes. An attribute will be cleared if its flag is not OR'd into attrib. An attribute will be set if its flag is OR'd into attrib. If another flag besides these are set, then an error will be returned. The attributes of the root directory may NOT be set. 299 600-uC-FS-001.book Page 300 Wednesday, October 10, 2012 12:03 PM Appendix A A-5-2 FSEntry_Copy() void FSEntry_Copy (CPU_CHAR *name_full_src, CPU_CHAR *name_full_dest, CPU_BOOLEAN excl, FS_ERR *p_err); File Called from Code enabled by fs_entry.c Application not FS_CFG_RD_ONLY_EN Copy a file. ARGUMENTS name_full_src Name of the source file. See section 4-3 "C/FS File and Directory Names and Paths" on page 62. name_full_dest Name of the destination file. excl Indicates whether the creation of the new entry shall be exclusive DEF_YES, if the entry shall be copied only if name_full_dest does not exist. DEF_NO, if the entry shall be copied even if name_full_dest does exist. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NAME_INVALID FS_ERR_NAME_PATH_TOO_LONG FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED FS_ERR_BUF_NONE_AVAIL FS_ERR_DEV File copied successfully. Argument name_full_src or name_full_dest passed a NULL pointer. Entry name specified invalid OR volume could not be found. Entry name specified too long. Volume was not open. Volume was not mounted. Buffer not available. Device access error. Or entry error (See section B-8 "Entry Error Codes" on page 395). 300 600-uC-FS-001.book Page 301 Wednesday, October 10, 2012 12:03 PM RETURNED VALUE None. NOTES/WARNINGS name_full_src must be an existing file. It may not be an existing directory. If excl is DEF_NO, name_full_dest must either not exist or be an existing file; it may not be an existing directory. If excl is DEF_YES, name_full_dest must not exist. 301 600-uC-FS-001.book Page 302 Wednesday, October 10, 2012 12:03 PM Appendix A A-5-3 FSEntry_Create() void FSEntry_Create (CPU_CHAR *name_full, FS_FLAGS entry_type, CPU_BOOLEAN excl, FS_ERR *p_err); File Called from Code enabled by fs_entry.c Application; fs_mkdir() not FS_CFG_RD_ONLY_EN Create a file or directory. See also fs_mkdir(). ARGUMENTS name_full Name of the entry. See section 4-3 "C/FS File and Directory Names and Paths" on page 62. entry_type Indicates whether the new entry shall be a directory or a file (see Note #1) : FS_ENTRY_TYPE_DIR, if the entry shall be a directory. FS_ENTRY_TYPE_FILE, if the entry shall be a file. excl Indicates whether the creation of the new entry shall be exclusive (see Notes): DEF_YES, if the entry shall be created only if p_name_full does not exist. DEF_NO, if the entry shall be created even if p_name_full does exist. 302 600-uC-FS-001.book Page 303 Wednesday, October 10, 2012 12:03 PM p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NAME_INVALID FS_ERR_NAME_PATH_TOO_LONG FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED FS_ERR_BUF_NONE_AVAIL FS_ERR_DEV Entry created successfully. Argument name_full passed a NULL pointer. Entry name specified invalid OR volume could not be found. Entry name specified too long. Volume was not open. Volume was not mounted. Buffer not available. Device access error. Or entry error. RETURNED VALUE None. NOTES/WARNINGS If the entry exists and is a file, entry_type is FS_ENTRY_TYPE_FILE and excl is DEF_NO, then the existing entry will be truncated. If the entry exists and is a directory and entry_type is FS_ENTRY_TYPE_DIR, then no change will be made to the file system. If the entry exists and is a directory, dir is DEF_NO and excl is DEF_NO, then no change will be made to the file system. Similarly, if the entry exists and is a file, dir is DEF_YES and excl is DEF_NO, then no change will be made to the file system. The root directory may not be created. 303 600-uC-FS-001.book Page 304 Wednesday, October 10, 2012 12:03 PM Appendix A A-5-4 FSEntry_Del() void FSEntry_Del (CPU_CHAR FS_FLAGS FS_ERR *name_full, entry_type, *p_err); File Called from Code enabled by fs_entry.c Application; fs_rmdir(); not FS_CFG_RD_ONLY_EN fs_remove() Delete a file or directory. See also fs_remove() and fs_rmdir(). ARGUMENTS name_full Pointer to character string representing the name of the entry. See section 4-3 "C/FS File and Directory Names and Paths" on page 62. entry_type Indicates whether the entry MAY be a file (see Notes #1 and #2): FS_ENTRY_TYPE_DIR FS_ENTRY_TYPE_FILE FS_ENTRY_TYPE_ANY p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NAME_INVALID FS_ERR_NAME_PATH_TOO_LONG FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED FS_ERR_BUF_NONE_AVAIL FS_ERR_DEV 304 if the entry must be a dir. if the entry must be a file. if the entry may be any type. Entry date/time set successfully. Argument name_full passed a NULL pointer. Entry name specified invalid OR volume could not be found. Entry name specified too long. Volume was not open. Volume was not mounted. Buffer not available. Device access error. Or entry error. 600-uC-FS-001.book Page 305 Wednesday, October 10, 2012 12:03 PM RETURNED VALUE None. NOTES/WARNINGS When a file is removed, the space occupied by the file is freed and shall no longer be accessible. A directory can be removed only if it is an empty directory. The root directory cannot be deleted. 305 600-uC-FS-001.book Page 306 Wednesday, October 10, 2012 12:03 PM Appendix A A-5-5 FSEntry_Query() void FSEntry_Query (CPU_CHAR *name_full, FS_ENTRY_INFO *p_info, FS_ERR *p_err); File Called from Code enabled by fs_entry.c Application; fs_stat() N/A Get information about a file or directory. ARGUMENTS name_full Name of the entry. See section 4-3 "C/FS File and Directory Names and Paths" on page 62. p_info Pointer to structure that will receive the file information. p_err Pointer to variable that will the receive return error code from the function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NAME_INVALID FS_ERR_NAME_PATH_TOO_LONG FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED FS_ERR_BUF_NONE_AVAIL FS_ERR_DEV RETURNED VALUE None. NOTES/WARNINGS None. 306 File information obtained successfully. Argument name_full passed a NULL pointer. Entry name specified invalid OR volume could not be found. Entry name specified too long. Volume was not open. Volume was not mounted. Buffer not available. Device access error. 600-uC-FS-001.book Page 307 Wednesday, October 10, 2012 12:03 PM A-5-6 FSEntry_Rename() void FSEntry_Rename (CPU_CHAR *name_full_old, CPU_CHAR *name_full_new, CPU_BOOLEAN excl, FS_ERR *p_err); File Called from Code enabled by fs_entry.c Application; fs_rename() not FS_CFG_RD_ONLY_EN Rename a file or directory. See also fs_rename(). ARGUMENTS name_full_old Old path of the entry. See section 4-3 "C/FS File and Directory Names and Paths" on page 62. name_full_new New path of the entry. excl Indicates whether the creation of the new entry shall be exclusive (see Note #1): DEF_YES, if the entry shall be renamed only if name_full_new does not exist. DEF_NO, if the entry shall be renamed even if name_full_new does exist. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NAME_INVALID FS_ERR_NAME_PATH_TOO_LONG FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED File copied successfully. Argument name_full_old or name_full_new passed a NULL pointer. Entry name specified invalid OR volume could not be found. Entry name specified too long. Volume was not open. Volume was not mounted. 307 600-uC-FS-001.book Page 308 Wednesday, October 10, 2012 12:03 PM Appendix A FS_ERR_BUF_NONE_AVAIL FS_ERR_DEV Buffer not available. Device access error. RETURNED VALUE None. NOTES/WARNINGS If name_full_old and name_full_new specify entries on different volumes, then name_full_old MUST specify a file. If name_full_old specifies a directory, an error will be returned. If name_full_old and name_full_new specify the same entry, the volume will not be modified and no error will be returned. If name_full_old specifies a file: name_full_new must NOT specify a directory; if excl is DEF_NO and name_full_new is a file, it will be removed. If name_full_old specifies a directory: name_full_new must NOT specify a file if excl is DEF_NO and name_full_new is a directory, name_full_new MUST be empty; if so, it will be removed. If excl is DEF_NO, name_full_new must not exist. The root directory may NOT be renamed. 308 600-uC-FS-001.book Page 309 Wednesday, October 10, 2012 12:03 PM A-5-7 FSEntry_TimeSet() void FSEntry_TimeSet (CPU_CHAR *name_full, FS_DATE_TIME *p_time, CPU_INT08U flag, FS_ERR *p_err); File Called from Code enabled by fs_entry.c Application not FS_CFG_RD_ONLY_EN Set a file or directory's date/time. ARGUMENTS name_full Name of the entry. See section 4-3 "C/FS File and Directory Names and Paths" on page 62. p_time Pointer to date/time. flag Flag to indicate which Date/Time should be set FS_DATE_TIME_CREATE FS_DATE_TIME_MODIFY FS_DATE_TIME_ACCESS FS_DATE_TIME_ALL p_err Entry Created Date/Time will be set. Entry Modified Date/Time will be set. Entry Accessed Date will be set. All the above will be set. Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_FILE_INVALID_DATE_TIME FS_ERR_NAME_INVALID FS_ERR_NAME_PATH_TOO_LONG FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED FS_ERR_BUF_NONE_AVAIL FS_ERR_DEV Entry date/time set successfully. Argument name_full or p_time passed a NULL pointer. Date/time specified invalid. Entry name specified invalid OR volume could not be found. Entry name specified too long. Volume was not open. Volume was not mounted. Buffer not available. Device access error. 309 600-uC-FS-001.book Page 310 Wednesday, October 10, 2012 12:03 PM Appendix A RETURNED VALUE None. NOTES/WARNINGS None. 310 600-uC-FS-001.book Page 311 Wednesday, October 10, 2012 12:03 PM A-6 FILE FUNCTIONS void FSFile_BufAssign (FS_FILE void FS_FLAGS CPU_SIZE_T FS_ERR *p_file, *p_buf, mode, size, *p_err); void FSFile_BufFlush (FS_FILE FS_ERR *p_file, *p_err); void FSFile_Close void FSFile_ClrErr CPU_BOOLEAN FSFile_IsEOF CPU_BOOLEAN FSFile_IsErr CPU_BOOLEAN FSFile_IsOpen (FS_FILE FS_ERR *p_file, *p_err); (FS_FILE FS_ERR *p_file, *p_err); (FS_FILE FS_ERR *p_file, *p_err); (FS_FILE FS_ERR *p_file, *p_err); (CPU_CHAR FS_FLAGS FS_ERR *name_full, *p_mode, *p_err); void FSFile_LockAccept(FS_FILE FS_ERR void FSFile_LockGet (FS_FILE FS_ERR *p_file, *p_err); *p_file, *p_err); 311 600-uC-FS-001.book Page 312 Wednesday, October 10, 2012 12:03 PM Appendix A void FSFile_LockSet FS_FILE * FSFile_Open FS_FILE_SIZE FSFile_PosGet void FSFile_PosSet void FSFile_Query CPU_SIZE_T FSFile_Rd (FS_FILE FS_ERR *p_file, *p_err); (CPU_CHAR FS_FLAGS FS_ERR *name_full, mode *p_err); (FS_FILE FS_ERR *p_file, *p_err); (FS_FILE *p_file, FS_FILE_OFFSET offset, FS_FLAGS origin, FS_ERR *p_err); (FS_FILE FS_ENTRY_INFO FS_ERR *p_file, *p_info, *p_err); (FS_FILE void CPU_SIZE_T FS_ERR *p_file, *p_dest, size, *p_err); void FSFile_Truncate (FS_FILE FS_FILE_SIZE FS_ERR CPU_SIZE_T FSFile_Wr 312 (FS_FILE void CPU_SIZE_T FS_ERR *p_file, size, *p_err); *p_file, *p_src, size, *p_err); 600-uC-FS-001.book Page 313 Wednesday, October 10, 2012 12:03 PM A-6-1 FSFile_BufAssign() void FSFile_BufAssign (FS_FILE *p_file, void *p_buf, FS_FLAGS mode, CPU_SIZE_T size, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; FS_CFG_FILE_BUF_EN fs_setbuf(); fs_setvbuf() Assign buffer to a file. See fs_setvbuf() for more information. ARGUMENTS p_file Pointer to a file. p_buf Pointer to buffer. mode Buffer mode: FS_FILE_BUF_MODE_RD FS_FILE_BUF_MODE_WR FS_FILE_BUF_MODE_RD_WR FS_FILE_BUF_MODE_SEC_ALIGNED size Data buffered for reads. Data buffered for writes. Data buffered for reads and writes. Force buffers to be aligned on sector boundaries. Size of buffer, in octets. 313 600-uC-FS-001.book Page 314 Wednesday, October 10, 2012 12:03 PM Appendix A p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR File buffer assigned. Argument p_file or p_buf passed a NULL pointer. FS_ERR_INVALID_TYPE Argument p_file's type is invalid or unknown. FS_ERR_FILE_INVALID_BUF_MODE Invalid buffer mode. FS_ERR_FILE_INVALID_BUF_SIZE Invalid buffer size. FS_ERR_FILE_BUF_ALREADY_ASSIGNED Buffer already assigned. FS_ERR_FILE_NOT_OPEN File NOT open. RETURNED VALUE None. NOTES/WARNINGS None. 314 600-uC-FS-001.book Page 315 Wednesday, October 10, 2012 12:03 PM A-6-2 FSFile_BufFlush() void FSFile_BufFlush (FS_FILE *p_file, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; FS_CFG_FILE_BUF_EN fs_fflush() Flush buffer contents to file. See fs_fflush() for more information. ARGUMENTS p_file Pointer to a file. p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN File buffer flushed successfully. Argument p_file passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. RETURNED VALUE None. NOTES/WARNINGS None. 315 600-uC-FS-001.book Page 316 Wednesday, October 10, 2012 12:03 PM Appendix A A-6-3 FSFile_Close() void FSFile_Close (FS_FILE *p_file, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; N/A fs_fclose() Close and free a file. See fs_fclose() for more information. ARGUMENTS p_file Pointer to a file. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN RETURNED VALUE None. NOTES/WARNINGS None. 316 File closed. Argument p_file passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. 600-uC-FS-001.book Page 317 Wednesday, October 10, 2012 12:03 PM A-6-4 FSFile_ClrErr() void FSFile_ClrErr (FS_FILE *p_file, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; N/A fs_clearerr() Clear EOF and error indicators on a file. See fs_clearerr() for more information ARGUMENTS p_file Pointer to a file. p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN Error and end-of-file indicators cleared. Argument p_file passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. RETURNED VALUE None. NOTES/WARNINGS None. 317 600-uC-FS-001.book Page 318 Wednesday, October 10, 2012 12:03 PM Appendix A A-6-5 FSFile_IsEOF() CPU_BOOLEAN FSFile_IsEOF (FS_FILE *p_file, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; N/A fs_feof() Test EOF indicator on a file. See fs_feof() for more information. ARGUMENTS p_file Pointer to a file. p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN EOF indicator obtained. Argument p_file passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. RETURNED VALUE DEF_NO if EOF indicator is NOT set or if an error occurred DEF_YES if EOF indicator is set. NOTES/WARNINGS None. 318 600-uC-FS-001.book Page 319 Wednesday, October 10, 2012 12:03 PM A-6-6 FSFile_IsErr() CPU_BOOLEAN FSFile_IsErr (FS_FILE *p_file, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; N/A fs_ferr() Test error indicator on a file. See fs_ferror() for more information. ARGUMENTS p_file Pointer to a file. p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN Error indicator obtained. Argument p_file passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. RETURNED VALUE DEF_NO if error indicator is NOT set or if an error occurred DEF_YES if error indicator is set. NOTES/WARNINGS None. 319 600-uC-FS-001.book Page 320 Wednesday, October 10, 2012 12:03 PM Appendix A A-6-7 FSFile_IsOpen() CPU_BOOLEAN FSFile_IsOpen (CPU_CHAR *name_full, FS_FLAGS *p_mode FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; FSFile_Open() N/A Test if file is already open. ARGUMENTS name_full Name of the file. See section 4-3 "C/FS File and Directory Names and Paths" on page 62 for information about file names. p_mode Pointer to variable that will receive the file access mode (see section 6-1-1 "Opening Files" on page 85 for the description the file access mode). p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_BUF_NONE_AVAIL FS_ERR_ENTRY_NOT_FILE FS_ERR_NAME_INVALID FS_ERR_VOL_INVALID_SEC_NBR RETURNED VALUE DEF_NO if file is NOT open DEF_YES if file is open. NOTES/WARNINGS None. 320 Error indicator obtained. Argument p_file passed a NULL pointer. No buffer available. Entry NOT a file. Invalid file name or path. Invalid sector number found in directory entry. 600-uC-FS-001.book Page 321 Wednesday, October 10, 2012 12:03 PM A-6-8 FSFile_LockAccept() void FSFile_LockAccept (FS_FILE *p_file, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; FS_CFG_FILE_LOCK_EN fs_ftrylockfile() Acquire task ownership of a file (if available). See fs_flockfile() for more information. ARGUMENTS p_file Pointer to a file. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN FS_ERR_FILE_LOCKED File lock acquired. Argument p_file passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. File owned by another task. RETURNED VALUE None. NOTES/WARNINGS None. 321 600-uC-FS-001.book Page 322 Wednesday, October 10, 2012 12:03 PM Appendix A A-6-9 FSFile_LockGet() void FSFile_LockGet (FS_FILE *p_file, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; FS_CFG_FILE_LOCK_EN fs_flockfile() Acquire task ownership of a file. See fs_flockfile() for more information. ARGUMENTS p_file Pointer to a file. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN RETURNED VALUE None. NOTES/WARNINGS None. 322 File lock acquired. Argument p_file passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. 600-uC-FS-001.book Page 323 Wednesday, October 10, 2012 12:03 PM A-6-10 FSFile_LockSet() void FSFile_LockSet (FS_FILE *p_file, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; FS_CFG_FILE_LOCK_EN fs_funlockfile() Release task ownership of a file. See fs_funlockfile() for more information. ARGUMENTS p_file Pointer to a file. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN FS_ERR_FILE_NOT_LOCKED File lock acquired. Argument p_file passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. File NOT locked or locked by different task. RETURNED VALUE None. NOTES/WARNINGS None. 323 600-uC-FS-001.book Page 324 Wednesday, October 10, 2012 12:03 PM Appendix A A-6-11 FSFile_Open() FS_FILE *FSFile_Open (CPU_CHAR *name_full, FS_FLAGS mode FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; fs_fopen() N/A Open a file. See fs_fopen() for more information. ARGUMENTS name_full Name of the file. See section 4-3 "C/FS File and Directory Names and Paths" on page 62 for information about file names. mode File access mode (see Notes #1 and #2). p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL File opened. Argument name_full passed a NULL pointer. Or entry error (see Section B.04). RETURNED VALUE None. NOTES/WARNINGS The access mode should be the logical OR of one or more flags : FS_FILE_ACCESS_MODE_RD FS_FILE_ACCESS_MODE_WR FS_FILE_ACCESS_MODE_CREATE FS_FILE_ACCESS_MODE_TRUNC 324 File File File File opened for reads. opened for writes. will be created, if necessary. length will be truncated to 0. 600-uC-FS-001.book Page 325 Wednesday, October 10, 2012 12:03 PM FS_FILE_ACCESS_MODE_APPEND FS_FILE_ACCESS_MODE_EXCL FS_FILE_ACCESS_MODE_CACHED All writes will be performed at EOF. File will be opened if and only if it does not already exist. File data will be cached. If FS_FILE_ACCESS_MODE_TRUNC is set, then FS_FILE_ACCESS_MODE_WR must also be set. If FS_FILE_ACCESS_MODE_EXCL is set, then FS_FILE_ACCESS_MODE_CREATE must also be set. FS_FILE_ACCESS_MODE_RD and/or FS_FILE_ACCESS_MODE_WR must be set. The mode string argument of fs_fopen() function can specify a subset of the possible valid modes for this function. The equivalent modes of fs_fopen() mode strings are shown in Table 5-4. fopen() Mode String mode Equivalent "r" or "rb" FS_FILE_ACCESS_MODE_RD "w" or "wb" FS_FILE_ACCESS_MODE_WR | FS_FILE_ACCESS_MODE_CREATE | FS_FILE_ACCESS_MODE_TRUNC "a" or "ab" FS_FILE_ACCESS_MODE_WR | FS_FILE_ACCESS_MODE_CREATE | FS_FILE_ACCESS_MODE_APPEND "r+" or "rb+" or "r+b" FS_FILE_ACCESS_MODE_RD FS_FILE_ACCESS_MODE_WR | "w+" or "wb+" or "w+b" FS_FILE_ACCESS_MODE_RD FS_FILE_ACCESS_MODE_WR | | FS_FILE_ACCESS_MODE_CREATE | FS_FILE_ACCESS_MODE_TRUNC "a+" or "ab+" or "a+b" FS_FILE_ACCESS_MODE_RD | FS_FILE_ACCESS_MODE_WR | FS_FILE_ACCESS_MODE_CREATE | FS_FILE_ACCESS_MODE_APPEND Table A-1 fs_fopen() mode strings and mode equivalents. 325 600-uC-FS-001.book Page 326 Wednesday, October 10, 2012 12:03 PM Appendix A A-6-12 FSFile_PosGet() FS_FILE_SIZE FSFile_PosGet (FS_FILE *p_file, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; N/A fs_ftell(); fs_fgetpos() Set file position indicator. See fs_ftell() for more information. ARGUMENTS p_file Pointer to a file. p_err Pointer to variable that will the receive return error code from the function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN FS_ERR_FILE_INVALID_POS File position gotten successfully. Argument p_file passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. Invalid file position. RETURNED VALUE The current file position, if no errors (see Note). 0, otherwise. NOTES/WARNINGS The file position returned is the number of bytes from the beginning of the file up to the current file position. 326 600-uC-FS-001.book Page 327 Wednesday, October 10, 2012 12:03 PM A-6-13 FSFile_PosSet() void FSFile_PosSet (FS_FILE *p_file, FS_FILE_OFFSET offset, FS_FLAGS origin, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; fs_fseek(); N/A fs_fsetpos() Get file position indicator. See fs_fseek() for more information. ARGUMENTS p_file Pointer to a file. offset Offset from the file position specified by origin. origin Reference position for offset: FS_FILE_ORIGIN_START FS_FILE_ORIGIN_CUR FS_FILE_ORIGIN_END p_err Offset is from the beginning of the file. Offset is from the current file position. Offset is from the end of the file. Pointer to variable that will the receive return error code from the function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_INVALID_ORIGIN FS_ERR_FILE_INVALID_OFFSET FS_ERR_FILE_NOT_OPEN File position set successfully. Argument p_file passed a NULL pointer. Argument p_file's type is invalid or unknown. Invalid origin specified. Invalid offset specified. File NOT open. 327 600-uC-FS-001.book Page 328 Wednesday, October 10, 2012 12:03 PM Appendix A RETURNED VALUE None. NOTES/WARNINGS None. 328 600-uC-FS-001.book Page 329 Wednesday, October 10, 2012 12:03 PM A-6-14 FSFile_Query() void FSFile_Query (FS_FILE *p_file, FS_ENTRY_INFO *p_info, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; fs_fstat() N/A FSFile_Query() is used to get information about a file. ARGUMENTS p_file Pointer to a file. p_info Pointer to structure that will receive the file information (see Note). p_err Pointer to variable that will the receive return error code from the function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN File information obtained successfully. Argument p_file or p_info passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. RETURNED VALUE None. NOTES/WARNINGS None. 329 600-uC-FS-001.book Page 330 Wednesday, October 10, 2012 12:03 PM Appendix A A-6-15 FSFile_Rd() CPU_SIZE_T FSFile_Rd (FS_FILE *p_file, void *p_dest, CPU_SIZE_T size, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; fs_fread() N/A Read from a file. See fs_fread() for more information. ARGUMENTS p_file Pointer to a file. p_dest Pointer to destination buffer. size Number of octets to read. p_err Pointer to variable that will the receive return error code from the function: FS_ERR_NONE FS_ERR_EOF FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN FS_ERR_FILE_INVALID_OP FS_ERR_DEV 330 File read successfully. End-of-file reached. Argument p_file/p_dest passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. Invalid operation on file. Device access error. 600-uC-FS-001.book Page 331 Wednesday, October 10, 2012 12:03 PM RETURNED VALUE The number of bytes read, if file read successful. 0, otherwise. NOTES/WARNINGS None. 331 600-uC-FS-001.book Page 332 Wednesday, October 10, 2012 12:03 PM Appendix A A-6-16 FSFile_Truncate() void FSFile_Truncate (FS_FILE *p_file, FS_FILE_SIZE size, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; fs_ftruncate() not FS_CFG_RD_ONLY_EN Truncate a file. See fs_ftruncate() for more information. ARGUMENTS p_file Pointer to a file. size Size of the file after truncation p_err Pointer to variable that will the receive return error code from the function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN RETURNED VALUE None. NOTES/WARNINGS None. 332 File truncated successfully. Argument p_file passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. 600-uC-FS-001.book Page 333 Wednesday, October 10, 2012 12:03 PM A-6-17 FSFile_Wr() CPU_SIZE_T FSFile_Wr (FS_FILE *p_file, void *p_src, CPU_SIZE_T size, FS_ERR *p_err); File Called from Code enabled by fs_file.c Application; fs_fwrite() not FS_CFG_RD_ONLY_EN Write to a file. See fs_fwrite() for more information. ARGUMENTS p_file Pointer to a file. p_src Pointer to source buffer. size Number of octets to write. p_err Pointer to variable that will the receive return error code from the function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_INVALID_TYPE FS_ERR_FILE_NOT_OPEN FS_ERR_FILE_INVALID_OP FS_ERR_DEV File write successfully. Argument p_file/p_src passed a NULL pointer. Argument p_file's type is invalid or unknown. File NOT open. Invalid operation on file. Device access error. 333 600-uC-FS-001.book Page 334 Wednesday, October 10, 2012 12:03 PM Appendix A RETURNED VALUE The number of bytes written, if file write successful. 0, otherwise. NOTES/WARNINGS None. 334 600-uC-FS-001.book Page 335 Wednesday, October 10, 2012 12:03 PM A-7 VOLUME FUNCTIONS void FSVol_Close void FSVol_Fmt (CPU_CHAR FS_ERR *name_vol, *p_err); (CPU_CHAR void FS_ERR *name_vol, *p_fs_cfg, *p_err); void FSVol_GetDfltVolName (CPU_CHAR FS_QTY FSVol_GetVolCnt (void); FS_QTY FSVol_GetVolCntMax (void); void FSVol_GetVolName CPU_BOOLEAN FSVol_IsMounted void FSVol_LabelGet void FSVol_LabelSet void FSVol_Open *name_vol); (FS_QTY CPU_CHAR vol_nbr, *name_vol); (CPU_CHAR *name_vol); (CPU_CHAR CPU_CHAR CPU_SIZE_T FS_ERR *name_vol, *label, len_max, *p_err); (CPU_CHAR CPU_CHAR FS_ERR *name_vol, *label, *p_err); (CPU_CHAR *name_vol, CPU_CHAR *name_dev, FS_PARTITION_NBR partition_nbr, FS_ERR *p_err); 335 600-uC-FS-001.book Page 336 Wednesday, October 10, 2012 12:03 PM Appendix A void FSVol_Query void FSVol_Rd void FSVol_Wr 336 (CPU_CHAR FS_VOL_INFO FS_ERR *name_vol, *p_info, *p_err); (CPU_CHAR void FS_SEC_NBR FS_SEC_QTY FS_ERR *name_vol, *p_dest, start, cnt, *p_err); (CPU_CHAR void FS_SEC_NBR FS_SEC_QTY FS_ERR *name_vol, *p_src, start, cnt, *p_err); 600-uC-FS-001.book Page 337 Wednesday, October 10, 2012 12:03 PM A-7-1 FSVol_Close() void FSVol_Close (CPU_CHAR *name_vol, FS_ERR *p_err); File Called from Code enabled by fs_vol.c Application N/A Close and free a volume. ARGUMENTS name_vol Volume name. p_err Pointer to variable that will receive the return error code from this function. See Note #2. FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_VOL_NOT_OPEN Volume opened. Argument name_vol passed a NULL pointer. Volume not open. RETURNED VALUE None. NOTES/WARNINGS None. 337 600-uC-FS-001.book Page 338 Wednesday, October 10, 2012 12:03 PM Appendix A A-7-2 FSVol_Fmt() void FSVol_Fmt (CPU_CHAR *name_vol, void *p_fs_cfg, FS_ERR *p_err); File Called from Code enabled by fs_vol.c Application not FS_CFG_RD_ONLY_EN Format a volume. ARGUMENTS name_vol Colume name. p_fs_cfg Pointer to file system driver-specific configuration. For all file system drivers, if this is a pointer to NULL, then the default configuration will be selected. More information about the appropriate structure for the FAT file system driver can be found in Chapter 6. p_err Pointer to variable that will receive the return error code from this function FS_ERR_NONE FS_ERR_DEV FS_ERR_DEV_INVALID_SIZE FS_ERR_NAME_NULL FS_ERR_VOL_DIRS_OPEN FS_ERR_VOL_FILES_OPEN FS_ERR_VOL_INVALID_SYS FS_ERR_VOL_NOT_OPEN REQUIRED CONFIGURATION None. 338 Volume formatted. Device error. Invalid device size. Argument name_vol passed a NULL pointer. Directories open on volume. Files open on volume. Invalid file system parameters. Volume not open. 600-uC-FS-001.book Page 339 Wednesday, October 10, 2012 12:03 PM NOTES/WARNINGS Function blocked if files or directories are open on the volume. All files and directories must be closed prior to formatting the volume. For any file system driver, if p_fs_cfg is a pointer to NULL, then the default configuration will be selected. If non-NULL, the argument should be passed a pointer to the appropriate configuration structure. For the FAT file system driver, p_fs_cfg should be passed a pointer to a FS_FAT_SYS_CFG. 339 600-uC-FS-001.book Page 340 Wednesday, October 10, 2012 12:03 PM Appendix A A-7-3 FSVol_GetDfltVolName() void FSVol_GetDfltVolName (CPU_CHAR *name_vol); File Called from Code enabled by fs_vol.c Application N/A Get name of the default volume. ARGUMENTS name_vol String buffer that will receive the volume name (see Note #2). RETURNED VALUE None. NOTES/WARNINGS name_vol MUST point to a character array of FS_CFG_MAX_VOL_NAME_LEN characters. If the volume does not exist, name_vol will receive an empty string. 340 600-uC-FS-001.book Page 341 Wednesday, October 10, 2012 12:03 PM A-7-4 FSVol_GetVolCnt() FS_QTY FSVol_GetVolCnt (void); File Called from Code enabled by fs_vol.c Application N/A Get the number of open volumes. ARGUMENTS None. RETURNED VALUE Number of volumes currently open. NOTES/WARNINGS None. 341 600-uC-FS-001.book Page 342 Wednesday, October 10, 2012 12:03 PM Appendix A A-7-5 FSVol_GetVolCntMax() FS_QTY FSVol_GetVolCntMax (void); File Called from Code enabled by fs_vol.c Application N/A Get the maximum possible number of open volumes. ARGUMENTS None. RETURNED VALUE The maximum number of open volumes. NOTES/WARNINGS None. 342 600-uC-FS-001.book Page 343 Wednesday, October 10, 2012 12:03 PM A-7-6 FSVol_GetVolName() void FSVol_GetVolName (FS_QTY vol_nbr, CPU_CHAR *name_vol); File Called from Code enabled by fs_vol.c Application N/A Get name of the nth open volume. vol_nbr should be between 0 and the return value of FSVol_GetNbrVols() (inclusive). ARGUMENTS vol_nbr Volume number. name_vol String buffer that will receive the volume name (see Note #2). RETURNED VALUE None. NOTES/WARNINGS name_vol MUST point to a character array of FS_CFG_MAX_VOL_NAME_LEN characters. If the volume does not exist, name_vol will receive an empty string. 343 600-uC-FS-001.book Page 344 Wednesday, October 10, 2012 12:03 PM Appendix A A-7-7 FSVol_IsDflt() CPU_BOOLEAN FSVol_IsDflt (CPU_CHAR *name_vol); File Called from Code enabled by fs_vol.c Application N/A Determine whether a volume is the default volume. ARGUMENTS name_vol Volume name. RETURNED VALUE DEF_YES, if the volume with name name_vol is the default volume. DEF_NO, if no volume with name name_vol exists. DEF_NO, or the volume with name name_vol is not the default volume. NOTES/WARNINGS None. 344 600-uC-FS-001.book Page 345 Wednesday, October 10, 2012 12:03 PM A-7-8 FSVol_IsMounted() CPU_BOOLEAN FSVol_IsMounted (CPU_CHAR *name_vol); File Called from Code enabled by fs_vol.c Application N/A Determine whether a volume is mounted. ARGUMENTS name_vol Volume name. RETURNED VALUE DEF_YES, if the volume is open and is mounted. DEF_NO, if the volume is not open or is not mounted. NOTES/WARNINGS None. 345 600-uC-FS-001.book Page 346 Wednesday, October 10, 2012 12:03 PM Appendix A A-7-9 FSVol_LabelGet() void FSVol_LabelGet (CPU_CHAR *name_vol, CPU_CHAR *label, CPU_SIZE_T len_max, FS_ERR *p_err); File Called from Code enabled by fs_vol.c Application N/A Get volume label. ARGUMENTS name_vol Volume name. label String buffer that will receive volume label. len_max Size of string buffer. p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_DEV_CHNGD FS_ERR_NAME_NULL FS_ERR_NULL_PTR FS_ERR_DEV FS_ERR_VOL_LABEL_NOT_FOUND FS_ERR_VOL_LABEL_TOO_LONG FS_ERR_VOL_NOT_MOUNTED FS_ERR_VOL_NOT_OPEN 346 Label gotten. Device has changed. Argument name_vol passed a NULL pointer. Argument label passed a NULL pointer. Device access error. Volume label was not found. Volume label is too long. Volume is not mounted. Volume is not open. 600-uC-FS-001.book Page 347 Wednesday, October 10, 2012 12:03 PM REQUIRED CONFIGURATION None. NOTES/WARNINGS len_max is the maximum length string that can be stored in the buffer label; it does NOT include the final NULL character. The buffer label MUST be of at least len_max + 1 characters. 347 600-uC-FS-001.book Page 348 Wednesday, October 10, 2012 12:03 PM Appendix A A-7-10 FSVol_LabelSet() void FSVol_LabelSet (CPU_CHAR *name_vol, CPU_CHAR *label, FS_ERR *p_err); File Called from Code enabled by fs_vol.c Application not FS_CFG_RD_ONLY_EN Set volume label. ARGUMENTS name_vol Volume name. label Volume label. p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_DEV_CHNGD FS_ERR_NAME_NULL FS_ERR_NULL_PTR FS_ERR_DEV FS_ERR_DIR_FULL FS_ERR_DEV_FULL FS_ERR_VOL_LABEL_INVALID FS_ERR_VOL_LABEL_TOO_LONG FS_ERR_VOL_NOT_MOUNTED FS_ERR_VOL_NOT_OPEN 348 Label set. Device has changed. Argument name_vol passed a NULL pointer. Argument label passed a NULL pointer. Device access error. Directory is full (space could not be allocated). Device is full (space could not be allocated). Volume label is invalid. Volume label is too long. Volume is not mounted. Volume is not open. 600-uC-FS-001.book Page 349 Wednesday, October 10, 2012 12:03 PM RETURNED VALUE None. NOTES/WARNINGS The label on a FAT volume must be no longer than 11-characters, each belonging to the set of valid short file name (SFN) characters. Before it is committed to the volume, the label will be converted to upper case and will be padded with spaces until it is an 11-character string. 349 600-uC-FS-001.book Page 350 Wednesday, October 10, 2012 12:03 PM Appendix A A-7-11 FSVol_Open() void FSVol_Open (CPU_CHAR *name_vol, CPU_CHAR *name_dev, FS_PARTITION_NBR partition_nbr, FS_ERR *p_err); File Called from Code enabled by fs_vol.c Application N/A Open a volume. ARGUMENTS name_vol Volume name. See Section 2.04 for information about device names. name_dev Device name. partition_nbr p_err Partition number. If 0, the default partition will be mounted. Pointer to variable that will receive the return error code from this function. See Note #2. FS_ERR_NONE FS_ERR_DEV_VOL_OPEN FS_ERR_INVALID_SIG FS_ERR_NAME_NULL FS_ERR_PARTITION_INVALID_NBR FS_ERR_PARTITION_NOT_FOUND FS_ERR_VOL_ALREADY_OPEN FS_ERR_VOL_INVALID_NAME FS_ERR_VOL_NONE_AVAIL Volume opened. Volume open on device. Invalid MBR signature. Argument name_vol / name_dev passed a NULL pointer. Invalid partition number. Partition not found. Volume is already open. Volume name invalid. No volumes available. Or device access error (see section B-4 "Device Error Codes" on page 394). 350 600-uC-FS-001.book Page 351 Wednesday, October 10, 2012 12:03 PM RETURNED VALUE None. NOTES/WARNINGS If FS_ERR_PARTITION_NOT_FOUND is returned, then no valid partition (or valid file system) was found on the device. It is still placed on the list of used volumes; however, it cannot be addressed as a mounted volume (e.g., files cannot be accessed). Thereafter, unless a new device is inserted, the only valid commands are FSVol_Fmt(), which creates a file system on the device; FSVol_Close(), which frees the volume structure; FSVol_Query(), which returns information about the device. If FS_ERR_DEV, FS_ERR_DEV_NOT_PRESENT, FS_ERR_DEV_IO or FS_ERR_DEV_TIMEOUT is returned, then the volume has been added to the file system, though the underlying device is probably not present. The volume will need to be either closed and re-added, or refreshed. 351 600-uC-FS-001.book Page 352 Wednesday, October 10, 2012 12:03 PM Appendix A A-7-12 FSVol_Query() void FSVol_Query (CPU_CHAR *name_vol, FS_VOL_INFO *p_info, FS_ERR *p_err); File Called from Code enabled by fs_vol.c Application N/A Obtain information about a volume. ARGUMENTS name_vol Volume name. p_info Pointer to structure that will receive volume information (see Note). p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_DEV FS_ERR_NAME_NULL FS_ERR_NULL_PTR FS_ERR_VOL_NOT_OPEN RETURNED VALUE None. NOTES/WARNINGS None. 352 Volume information obtained. Device access error. Argument name_vol passed a NULL pointer. Argument p_info passed a NULL pointer. Volume is not open. 600-uC-FS-001.book Page 353 Wednesday, October 10, 2012 12:03 PM A-7-13 FSVol_Rd() void FSVol_Rd (CPU_CHAR *name_vol, void *p_dest, FS_SEC_NBR start, FS_SEC_QTY cnt, FS_ERR *p_err); File Called from Code enabled by fs_vol.c Application N/A Reads data from volume sector(s). ARGUMENTS name_vol Volume name. p_dest Pointer to destination buffer. start Start sector of read. cnt Number of sectors to read p_err Pointer to variable that will receive the return error code from this function FS_ERR_NONE FS_ERR_DEV FS_ERR_NAME_NULL FS_ERR_NULL_PTR FS_ERR_VOL_NOT_MOUNTED FS_ERR_VOL_NOT_OPEN Sector(s) read. Device access error. Argument name_vol passed a NULL pointer. Argument p_dest passed a NULL pointer. Volume is not mounted. Volume is not open. 353 600-uC-FS-001.book Page 354 Wednesday, October 10, 2012 12:03 PM Appendix A RETURNED VALUE None. REQUIRED CONFIGURATION None. NOTES/WARNINGS None. 354 600-uC-FS-001.book Page 355 Wednesday, October 10, 2012 12:03 PM A-7-14 FSVol_Wr() void FSVol_Wr (CPU_CHAR *name_vol, void *p_src, FS_SEC_NBR start, FS_SEC_QTY cnt, FS_ERR *p_err); File Called from Code enabled by fs_vol.c Application not FS_CFG_RD_ONLY_EN Writes data to volume sector(s). ARGUMENTS name_vol Volume name. p_src Pointer to source buffer. start Start sector of write. cnt Number of sectors to write p_err Pointer to variable that will receive the return error code from this function FS_ERR_NONE FS_ERR_DEV FS_ERR_NAME_NULL FS_ERR_NULL_PTR FS_ERR_VOL_NOT_MOUNTED FS_ERR_VOL_NOT_OPEN Sector(s) written. Device access error. Argument name_vol passed a NULL pointer. Argument p_src passed a NULL pointer. Volume is not mounted. Volume is not open. RETURNED VALUE None. NOTES/WARNINGS None. 355 600-uC-FS-001.book Page 356 Wednesday, October 10, 2012 12:03 PM Appendix A A-8 VOLUME CACHE FUNCTIONS void FSVol_CacheAssign (CPU_CHAR FS_VOL_CACHE_API void CPU_INT32U CPU_INT08U CPU_INT08U FS_FLAGS FS_ERR *name_vol, *p_cache_api, *p_cache_data, size, pct_mgmt, pct_dir, mode, *p_err); void FSVol_CacheInvalidate (CPU_CHAR *name_vol, FS_ERR *p_err); void FSVol_CacheFlush 356 (CPU_CHAR *name_vol, FS_ERR *p_err); 600-uC-FS-001.book Page 357 Wednesday, October 10, 2012 12:03 PM A-8-1 FSVol_CacheAssign() void FSVol_CacheAssign (CPU_CHAR FS_VOL_CACHE_API void CPU_INT32U CPU_INT08U CPU_INT08U FS_FLAGS FS_ERR *name_vol, *p_cache_api, *p_cache_data, size, pct_mgmt, pct_dir, mode, *p_err) File Called from Code enabled by fs_vol.c Application FS_CFG_CACHE_EN Assign cache to a volume. ARGUMENTS name_vol Volume name. p_cache_api Pointer to: (a) cache API to use; OR (b) NULL, if default cache API should be used. p_cache_data Pointer to cache data. size Size, in bytes, of cache buffer. pct_mgmt Percent of cache buffer dedicated to management sectors. pct_dir Percent of cache buffer dedicated to directory sectors. mode Cache mode FS_VOL_CACHE_MODE_WR_THROUGH FS_VOL_CACHE_MODE_WR_BACK FS_VOL_CACHE_MODE_RD 357 600-uC-FS-001.book Page 358 Wednesday, October 10, 2012 12:03 PM Appendix A p_err Pointer to variable that will receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_VOL_NOT_OPEN FS_ERR_NULL_PTR FS_ERR_CACHE_INVALID_MODE FS_ERR_CACHE_INVALID_SEC_TYPE FS_ERR_CACHE_TOO_SMALL RETURNED VALUE None. NOTES/WARNINGS None. 358 Cache created. `name_vol' passed a NULL pointer. Volume not open. `p_cache_data' passed a NULL pointer. Mode specified invalid Sector type sepecified invalid. Size specified too small for cache. 600-uC-FS-001.book Page 359 Wednesday, October 10, 2012 12:03 PM A-8-2 FSVol_CacheInvalidate () void FSVol_CacheInvalidate (CPU_CHAR *name_vol, FS_ERR *p_err) File Called from Code enabled by fs_vol.c Application FS_CFG_CACHE_EN Invalidate cache on a volume. ARGUMENTS name_vol Volume name. p_err Pointer to variable that will receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV_CHNGD FS_ERR_VOL_NO_CACHE FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED Cache created. `name_vol' passed a NULL pointer. Device has changed. No cache assigned to volume. Volume not open. Volume not mounted. RETURNED VALUE None. NOTES/WARNINGS None. 359 600-uC-FS-001.book Page 360 Wednesday, October 10, 2012 12:03 PM Appendix A A-8-3 FSVol_CacheFlush () void FSVol_CacheFlush (CPU_CHAR *name_vol, FS_ERR *p_err) File Called from Code enabled by fs_vol.c Application FS_CFG_CACHE_EN Flush cache on a volume. ARGUMENTS name_vol Volume name. p_err Pointer to variable that will receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV_CHNGD FS_ERR_VOL_NO_CACHE FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED FS_ERR_DEV_INVALID_SEC_NBR FS_ERR_DEV_INVALID_lOW_FMT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT FS_ERR_DEV_NOT_PRESENT RETURNED VALUE None. NOTES/WARNINGS None. 360 Cache created. `name_vol' passed a NULL pointer. Device has changed. No cache assigned to volume. Volume not open. Volume not mounted. Sector start or count invalid. Device needs to be low-level formatted. Device I/O error. Device timeout error. Device is not present. 600-uC-FS-001.book Page 361 Wednesday, October 10, 2012 12:03 PM A-9 SD/MMC DRIVER FUNCTIONS void FSDev_SD_Card_QuerySD (CPU_CHAR *name_dev, FS_DEV_SD_INFO *p_info, FS_ERR *p_err); void FSDev_SD_SPI_QuerySD (CPU_CHAR *name_dev, FS_DEV_SD_INFO *p_info, FS_ERR *p_err); void FSDev_SD_Card_RdCID void FSDev_SD_SPI_RdCID void FSDev_SD_Card_RdCSD void FSDev_SD_SPI_RdCSD (CPU_CHAR CPU_INT08U FS_ERR *name_dev, *p_info, *p_err); (CPU_CHAR CPU_INT08U FS_ERR *name_dev, *p_info, *p_err); (CPU_CHAR CPU_INT08U FS_ERR *name_dev, *p_info, *p_err); (CPU_CHAR CPU_INT08U FS_ERR *name_dev, *p_info, *p_err); 361 600-uC-FS-001.book Page 362 Wednesday, October 10, 2012 12:03 PM Appendix A A-9-1 FSDev_SD_xxx_QuerySD() void FSDev_SD_Card_QuerySD (CPU_CHAR FS_DEV_SD_INFO FS_ERR void FSDev_SD_SPI_QuerySD (CPU_CHAR FS_DEV_SD_INFO FS_ERR *name_dev, *p_info, *p_err); *name_dev, *p_info, *p_err); File Called from Code enabled by fs_dev_sd_card.c, fs_dev_sd_spi.c Application N/A Get low-level information abou SD/MMC card. ARGUMENTS name_dev Device name (see Note). p_info Pointer to structure that will receive SD/MMC card information. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NULL_PTR FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT 362 SD/MMC info obtained. Argument name_dev passed a NULL pointer. Argument p_info passed a NULL pointer. Argument name_dev specifies an invalid device Device is not open. Device is not present. Device I/O error. Device timeout. 600-uC-FS-001.book Page 363 Wednesday, October 10, 2012 12:03 PM RETURNED VALUE None. NOTES/WARNINGS The device must be a SD/MMC device; (for FSDev_SD_Card_QuerySD(), e.g., "sdcard:0:"; for FSDev_SD_SPI_QuerySD(), e.g., "sd:0:"). 363 600-uC-FS-001.book Page 364 Wednesday, October 10, 2012 12:03 PM Appendix A A-9-2 FSDev_SD_xxx_RdCID() void FSDev_SD_Card_RdCID (CPU_CHAR CPU_INT08U FS_ERR void FSDev_SD_SPI_RdCID (CPU_CHAR CPU_INT08U FS_ERR *name_dev, *p_info, *p_err); *name_dev, *p_info, *p_err); File Called from Code enabled by fs_dev_sd_card.c, fs_dev_sd_spi.c Application N/A Read SD/MMC Card ID (CID) register. ARGUMENTS name_dev Device name (see Note #1). p_dest Pointer to 16-byte buffer that will receive SD/MMC Card ID register. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NULL_PTR FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT 364 SD/MMC Card ID register read. Argument name_dev passed a NULL pointer. Argument p_dest passed a NULL pointer. Argument name_dev specifies an invalid device Device is not open. Device is not present. Device I/O error. Device timeout. 600-uC-FS-001.book Page 365 Wednesday, October 10, 2012 12:03 PM RETURNED VALUE None. NOTES/WARNINGS The device must be a SD/MMC device; (for FSDev_SD_Card_QuerySD(), e.g., "sdcard:0:"; for FSDev_SD_SPI_QuerySD(), e.g., "sd:0:"). For SD cards, the structure of the CID is defined in the SD Card Association's "Physical Layer Simplified Specification Version 2.00", Section 5.1. For MMC cards, the structure of the CID is defined in the JEDEC's "MultiMediaCard (MMC) Electrical Standard, High Capacity", Section 8.2. 365 600-uC-FS-001.book Page 366 Wednesday, October 10, 2012 12:03 PM Appendix A A-9-3 FSDev_SD_xxx_RdCSD() void FSDev_SD_Card_RdCSD (CPU_CHAR CPU_INT08U FS_ERR void FSDev_SD_SPI_RdCSD (CPU_CHAR CPU_INT08U FS_ERR *name_dev, *p_info, *p_err); *name_dev, *p_info, *p_err); File Called from Code enabled by fs_dev_sd_card.c, fs_dev_sd_spi.c Application N/A Read SD/MMC Card-Specific Data (CSD) register. ARGUMENTS name_dev Device name (see Note #1). p_dest Pointer to 16-byte buffer that will receive SD/MMC Card-Specific Data register. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NULL_PTR FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT 366 SD/MMC Card-Specific Data register read. Argument name_dev passed a NULL pointer. Argument p_dest passed a NULL pointer. Argument name_dev specifies an invalid device Device is not open. Device is not present. Device I/O error. Device timeout. 600-uC-FS-001.book Page 367 Wednesday, October 10, 2012 12:03 PM RETURNED VALUE None. NOTES/WARNINGS The device must be a SD/MMC device; (for FSDev_SD_Card_QuerySD(), e.g., "sdcard:0:"; for FSDev_SD_SPI_QuerySD(), e.g., "sd:0:"). For SD cards, the structure of the CSD is defined in the SD Card Association's "Physical Layer Simplified Specification Version 2.00", Section 5.3.2 (v1.x and v2.0 standard capacity) or Section 5.3.3. (v2.0 high capacity). For MMC cards, the structure of the CSD is defined in the JEDEC's "MultiMediaCard (MMC) Electrical Standard, High Capacity", Section 8.3. 367 600-uC-FS-001.book Page 368 Wednesday, October 10, 2012 12:03 PM Appendix A A-10 NAND DRIVER FUNCTIONS void FSDev_NAND_LowFmt (CPU_CHAR FS_ERR *name_dev, *p_err); (CPU_CHAR FS_ERR *name_dev, *p_err); void FSDev_NAND_LowUnmount (CPU_CHAR FS_ERR *name_dev, *p_err); void FSDev_NAND_LowMount 368 600-uC-FS-001.book Page 369 Wednesday, October 10, 2012 12:03 PM A-10-1 FSDev_NAND_LowFmt() void FSDev_NAND_LowFmt (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev_nand.c Application N/A Low-level format a NAND device. ARGUMENTS name_dev Device name (see Note). p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Device low-level formatted successfully. Argument name_dev passed a NULL pointer. Argument name_dev specifies an invalid device Device Device Device Device Device is not open. is not present. needs to be low-level formatted. I/O error. timeout. RETURNED VALUE None. NOTES/WARNINGS The device must be a NAND device (e.g., "nand:0:"). A NAND medium MUST be low-level formatted with this driver prior to access by the high-level file system, a requirement which the device module enforces. 369 600-uC-FS-001.book Page 370 Wednesday, October 10, 2012 12:03 PM Appendix A A-10-2 FSDev_NAND_LowMount() void FSDev_NAND_LowMount (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev_nand.c Application N/A Low-level mount a NAND device. ARGUMENTS name_dev Device name (see Note). p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL Device low-level mounted successfully. Argument name_dev passed a NULL pointer. FS_ERR_DEV_INVALID Argument name_dev specifies an invalid device FS_ERR_DEV_NOT_OPEN Device is not open. FS_ERR_DEV_NOT_PRESENT Device is not present. FS_ERR_CORRUPT_LOW_FMT Device low-level format corrupted. FS_ERR_DEV_INVALID_LOW_FMT Device needs to be low-level formatted. FS_ERR_DEV_INCOMPATIBLE_LOW_PARAMS Device configuration not compatible with existing format. S_ERR_DEV_IO Device I/O error. FS_ERR_DEV_TIMEOUT Device timeout. RETURNED VALUE None. NOTES/WARNINGS The device must be a NAND device (e.g., "nand:0:"). 370 600-uC-FS-001.book Page 371 Wednesday, October 10, 2012 12:03 PM Low-level mounting parses the on-device structure, detecting the presence of a valid low-level format. If FS_ERR_DEV_INVALID_LOW_FMT is returned, the device is NOT low-level formatted. If an existing on-device low-level format is found but doesn't match the format prompted by specified device configuration, FS_ERR_DEV_INCOMPATIBLE_LOW_PARAMS will be returned. A low-level format is required. If an existing and compatible on-device low-level format is found, but is not usable because of some metadata corruption, FS_ERR_DEV_CORRUPT_LOW_FMT will be returned. A chip erase and/or low-level format is required. 371 600-uC-FS-001.book Page 372 Wednesday, October 10, 2012 12:03 PM Appendix A A-10-3 FSDev_NAND_LowUnmount() void FSDev_NAND_LowUnmount (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev_nand.c Application N/A Low-level unmount a NAND device. ARGUMENTS name_dev Device name (see Note). p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Device low-level unmounted successfully. Argument name_dev passed a NULL pointer. Argument name_dev specifies an invalid device Device is not open. Device is not present. Device I/O error. Device timeout. RETURNED VALUE None. NOTES/WARNINGS The device must be a NAND device (e.g., "nand:0:"). Low-level unmounting clears software knowledge of the on-disk structures, forcing the device to again be low-level mounted or formatted prior to further use. 372 600-uC-FS-001.book Page 373 Wednesday, October 10, 2012 12:03 PM A-11 NOR DRIVER FUNCTIONS void FSDev_NOR_LowFmt void FSDev_NOR_LowMount void FSDev_NOR_LowUnmount void FSDev_NOR_LowCompact void FSDev_NOR_LowDefrag void FSDev_NOR_PhyRd void FSDev_NOR_PhyWr (CPU_CHAR FS_ERR *name_dev, *p_err); (CPU_CHAR FS_ERR *name_dev, *p_err); (CPU_CHAR FS_ERR *name_dev, *p_err); (CPU_CHAR FS_ERR *name_dev, *p_err); (CPU_CHAR FS_ERR *name_dev, *p_err); (CPU_CHAR *name_dev, void *p_dest, CPU_INT32U start, CPU_INT32U cnt, FS_ERR *p_err); (CPU_CHAR *name_dev, void *p_src, CPU_INT32U start, CPU_INT32U cnt, FS_ERR *p_err); void FSDev_NOR_PhyEraseBlk (CPU_CHAR *name_dev, CPU_INT32U start, CPU_INT32U size, FS_ERR *p_err); void FSDev_NOR_PhyEraseChip (CPU_CHAR FS_ERR *name_dev, *p_err); 373 600-uC-FS-001.book Page 374 Wednesday, October 10, 2012 12:03 PM Appendix A A-11-1 FSDev_NOR_LowFmt() void FSDev_NOR_LowFmt (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev_nor.c Application N/A Low-level format a NOR device. ARGUMENTS name_dev Device name (see Note). p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Device low-level formatted successfully. Argument name_dev passed a NULL pointer. Argument name_dev specifies an invalid device Device is not open. Device is not present. Device needs to be low-level formatted. Device I/O error. Device timeout. RETURNED VALUE None. NOTES/WARNINGS The device must be a NOR device (e.g., "nor:0:"). Low-level formating associates physical areas (sectors) of the device with logical sector numbers. A NOR medium MUST be low-level formatted with this driver prior to access by the high-level file system, a requirement which the device module enforces. 374 600-uC-FS-001.book Page 375 Wednesday, October 10, 2012 12:03 PM A-11-2 FSDev_NOR_LowMount() void FSDev_NOR_LowMount (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev_nor.c Application N/A Low-level mount a NOR device. ARGUMENTS name_dev Device name (see Note). p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Device low-level mounted successfully. Argument name_dev passed a NULL pointer. Argument name_dev specifies an invalid device Device is not open. Device is not present. Device needs to be low-level formatted. Device I/O error. Device timeout. RETURNED VALUE None. NOTES/WARNINGS The device must be a NOR device (e.g., "nor:0:"). Low-level mounting parses the on-device structure, detecting the presence of a valid low-level format. If FS_ERR_DEV_INVALID_LOW_FMT is returned, the device is NOT low-level formatted. 375 600-uC-FS-001.book Page 376 Wednesday, October 10, 2012 12:03 PM Appendix A A-11-3 FSDev_NOR_LowUnmount() void FSDev_NOR_LowUnmount (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev_nor.c Application N/A Low-level unmount a NOR device. ARGUMENTS name_dev Device name (see Note). p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Device low-level unmounted successfully. Argument name_dev passed a NULL pointer. Argument name_dev specifies an invalid device Device is not open. Device is not present. Device I/O error. Device timeout. RETURNED VALUE None. NOTES/WARNINGS The device must be a NOR device (e.g., "nor:0:"). Low-level unmounting clears software knowledge of the on-disk structures, forcing the device to again be low-level mounted or formatted prior to further use. 376 600-uC-FS-001.book Page 377 Wednesday, October 10, 2012 12:03 PM A-11-4 FSDev_NOR_LowCompact() void FSDev_NOR_LowCompact (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev_nor.c Application N/A Low-level compact a NOR device. ARGUMENTS name_dev Device name (see Note). p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Device low-level compacted successfully. Argument name_dev passed a NULL pointer. Argument name_dev specifies an invalid device Device is not open. Device is not present. Device needs to be low-level formatted. Device I/O error. Device timeout. RETURNED VALUE None. NOTES/WARNINGS The device must be a NOR device (e.g., "nor:0:"). Compacting groups sectors containing high-level data into as few blocks as possible. If an image of a file system is to be formed for deployment, to be burned into chips for production, then it should be compacted after all files and directories are created. 377 600-uC-FS-001.book Page 378 Wednesday, October 10, 2012 12:03 PM Appendix A A-11-5 FSDev_NOR_LowDefrag() void FSDev_NOR_LowDefrag (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev_nor.c Application N/A Low-level defragment a NOR device. ARGUMENTS name_dev Device name (see Note). p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Device low-level defragmented successfully. Argument name_dev passed a NULL pointer. Argument name_dev specifies an invalid device Device is not open. Device is not present. Device needs to be low-level formatted. Device I/O error. Device timeout. RETURNED VALUE None. NOTES/WARNINGS The device must be a NOR device (e.g., "nor:0:"). Defragmentation groups sectors containing high-level data into as few blocks as possible, in order of logical sector. A defragmented file system should have near-optimal access speeds in a read-only environment. 378 600-uC-FS-001.book Page 379 Wednesday, October 10, 2012 12:03 PM A-11-6 FSDev_NOR_PhyRd() void FSDev_NOR_PhyRd (CPU_CHAR *name_dev, void *p_dest, CPU_INT32U start, CPU_INT32U cnt, FS_ERR *p_err); File Called from Code enabled by fs_dev_nor.c Application N/A Read from a NOR device and store data in buffer. ARGUMENTS name_dev Device name (see Note). p_dest Pointer to destination buffer. start Start address of read (relative to start of device). cnt Number of octets to read. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NULL_PTR FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Octets read successfully. Argument name_dev passed a NULL pointer. Argument p_dest passed a NULL pointer. Argument name_dev specifies an invalid device. Device is not open. Device is not present. Device needs to be low-level formatted. Device I/O error. Device timeout. 379 600-uC-FS-001.book Page 380 Wednesday, October 10, 2012 12:03 PM Appendix A RETURNED VALUE None. NOTES/WARNINGS The device must be a NOR device (e.g., "nor:0:"). 380 600-uC-FS-001.book Page 381 Wednesday, October 10, 2012 12:03 PM A-11-7 FSDev_NOR_PhyWr() void FSDev_NOR_PhyWr (CPU_CHAR *name_dev, void *p_src, CPU_INT32U start, CPU_INT32U cnt, FS_ERR *p_err); File Called from Code enabled by fs_dev_nor.c Application N/A Write to a NOR device from a buffer. ARGUMENTS name_dev Device name (see Note). p_src Pointer to source buffer. start Start address of write (relative to start of device). cnt Number of octets to write. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_NULL_PTR FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Octets written successfully. Argument name_dev passed a NULL pointer. Argument p_src passed a NULL pointer. Argument name_dev specifies an invalid device. Device is not open. Device is not present. Device needs to be low-level formatted. Device I/O error. Device timeout. 381 600-uC-FS-001.book Page 382 Wednesday, October 10, 2012 12:03 PM Appendix A RETURNED VALUE None. NOTES/WARNINGS The device must be a NOR device (e.g., "nor:0:"). Care should be taken if this function is used while a file system exists on the device, or if the device is low-level formatted. The octet location(s) modified are NOT validated as being outside any existing file system or low-level format information. During a program operation, only 1 bits can be changed; a 0 bit cannot be changed to a 1. The application must know that the octets being programmed have not already been programmed. 382 600-uC-FS-001.book Page 383 Wednesday, October 10, 2012 12:03 PM A-11-8 FSDev_NOR_PhyEraseBlk() void FSDev_NOR_PhyEraseBlk (CPU_CHAR *name_dev, CPU_INT32U start, CPU_INT32U size, FS_ERR *p_err); File Called from Code enabled by fs_dev_nor.c Application N/A Erase block of NOR device. ARGUMENTS name_dev Device name (see Note). start Start address of block (relative to start of device). size Size of block, in octets. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Block erased successfully. Argument name_dev passed a NULL pointer. Argument name_dev specifies an invalid device Device is not open. Device is not present. Device needs to be low-level formatted. Device I/O error. Device timeout. 383 600-uC-FS-001.book Page 384 Wednesday, October 10, 2012 12:03 PM Appendix A RETURNED VALUE None. NOTES/WARNINGS The device must be a NOR device (e.g., "nor:0:"). Care should be taken if this function is used while a file system exists on the device, or if the device is low-level formatted. The erased block is NOT validated as being outside any existing file system or low-level format information. 384 600-uC-FS-001.book Page 385 Wednesday, October 10, 2012 12:03 PM A-11-9 FSDev_NOR_PhyEraseChip() void FSDev_NOR_PhyEraseChip (CPU_CHAR *name_dev, FS_ERR *p_err); File Called from Code enabled by fs_dev_nor.c Application N/A Erase entire NOR device. ARGUMENTS name_dev Device name (see Note). p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Device erased successfully. Argument name_dev passed a NULL pointer. Argument name_dev specifies an invalid device Device is not open. Device is not present. Device needs to be low-level formatted. Device I/O error. Device timeout. RETURNED VALUE None. NOTES/WARNINGS The device must be a NOR device (e.g., "nor:0:"). This function should not be used while a file system exists on the device, or if the device is low-level formatted, unless the intent is to destroy all existing information. 385 600-uC-FS-001.book Page 386 Wednesday, October 10, 2012 12:03 PM Appendix A A-12 FAT SYSTEM DRIVER FUNCTIONS void FS_FAT_JournalOpen (CPU_CHAR *name_vol, FS_ERR *p_err); void FS_FAT_JournalClose (CPU_CHAR *name_vol, FS_ERR *p_err); void FS_FAT_JournalStart (CPU_CHAR *name_vol, FS_ERR *p_err); void FS_FAT_JournalStop (CPU_CHAR *name_vol, FS_ERR *p_err); void FS_FAT_VolChk 386 (CPU_CHAR *name_vol, FS_ERR *p_err); 600-uC-FS-001.book Page 387 Wednesday, October 10, 2012 12:03 PM A-12-1 FS_FAT_JournalOpen() File Called from Code enabled by fs_fat_journal.c Application FS_CFG_FAT_JOURNAL_EN Open journal on volume. ARGUMENTS name_vol Volume name. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_DEV Journal opened. Device access error. RETURNED VALUE None. NOTES/WARNINGS None. 387 600-uC-FS-001.book Page 388 Wednesday, October 10, 2012 12:03 PM Appendix A A-12-2 FS_FAT_JournalClose() void FS_FAT_JournalClose (CPU_CHAR *name_vol, FS_ERR *p_err); File Called from Code enabled by fs_fat_journal.c Application FS_CFG_FAT_JOURNAL_EN Close journal on volume. ARGUMENTS name_vol Volume name. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_DEV RETURNED VALUE None. NOTES/WARNINGS None. 388 Journal closed. Device access error. 600-uC-FS-001.book Page 389 Wednesday, October 10, 2012 12:03 PM A-12-3 FS_FAT_JournalStart() void FS_FAT_JournalStart (CPU_CHAR *name_vol, FS_ERR *p_err); File Called from Code enabled by fs_fat_journal.c Application FS_CFG_FAT_JOURNAL_EN Start journaling on volume. ARGUMENTS name_vol Volume name. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_DEV Journaling started. Device access error. RETURNED VALUE None. NOTES/WARNINGS None. 389 600-uC-FS-001.book Page 390 Wednesday, October 10, 2012 12:03 PM Appendix A A-12-4 FS_FAT_JournalStop() void FS_FAT_JournalStop (CPU_CHAR *name_vol, FS_ERR *p_err); File Called from Code enabled by fs_fat_journal.c Application FS_CFG_FAT_JOURNAL_EN Stop journaling on volume. ARGUMENTS name_vol Volume name. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_DEV RETURNED VALUE None. NOTES/WARNINGS None. 390 Journaling stopped. Device access error. 600-uC-FS-001.book Page 391 Wednesday, October 10, 2012 12:03 PM A-12-5 FS_FAT_VolChk() File Called from Code enabled by fs_fat.c Application FS_CFG_FAT_VOL_CHK_EN Check the file system on a volume. ARGUMENTS name_vol Volume name. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NAME_NULL FS_ERR_DEV FS_ERR_VOL_NOT_OPEN FS_ERR_BUF_NONE_AVAIL Volume checked without errors. Argument "name_vol" passed a null pointer. Device access error. Volume not open. No buffers available. RETURNED VALUE None. NOTES/WARNINGS None. 391 600-uC-FS-001.book Page 392 Wednesday, October 10, 2012 12:03 PM Appendix A 392 600-uC-FS-001.book Page 393 Wednesday, October 10, 2012 12:03 PM Appendix B C/FS Error Codes This appendix provides a brief explanation of C/FS error codes defined in fs_err.h. Any error codes not listed here may be searched in fs_err.h for both their numerical value and usage. B-1 SYSTEM ERROR CODES FS_ERR_NONE FS_ERR_INVALID_ARG FS_ERR_INVALID_CFG FS_ERR_INVALID_CHKSUM FS_ERR_INVALID_LEN FS_ERR_INVALID_TIME FS_ERR_INVALID_TIMESTAMP FS_ERR_INVALID_TYPE FS_ERR_MEM_ALLOC FS_ERR_NULL_ARG FS_ERR_NULL_PTR FS_ERR_OS FS_ERR_OVF FS_ERR_EOF FS_ERR_WORKING_DIR_NONE_AVAIL FS_ERR_WORKING_DIR_INVALID No error. Invalid argument. Invalid configuration. Invalid checksum. Invalid length. Invalid date/time. Invalid timestamp. Invalid object type. Mem could not be alloc'd. Arg(s) passed NULL val(s). Ptr arg(s) passed NULL ptr(s). OS err. Value too large to be stored in type. EOF reached. No working dir avail. Working dir invalid. B-2 BUFFER ERROR CODES FS_ERR_BUF_NONE_AVAIL No buffer available. 393 600-uC-FS-001.book Page 394 Wednesday, October 10, 2012 12:03 PM Appendix B B-3 CACHE ERROR CODES FS_ERR_CACHE_INVALID_MODE FS_ERR_CACHE_INVALID_SEC_TYPE FS_ERR_CACHE_TOO_SMALL Mode specified invalid. Device already open. Device has changed. B-4 DEVICE ERROR CODES FS_ERR_DEV FS_ERR_DEV_ALREADY_OPEN FS_ERR_DEV_CHNGD FS_ERR_DEV_FIXED FS_ERR_DEV_FULL FS_ERR_DEV_INVALID FS_ERR_DEV_INVALID_CFG FS_ERR_DEV_INVALID_ECC FS_ERR_DEV_INVALID_IO_CTRL FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_INVALID_LOW_PARAMS FS_ERR_DEV_INVALID_MARK FS_ERR_DEV_INVALID_NAME FS_ERR_DEV_INVALID_OP FS_ERR_DEV_INVALID_SEC_NBR FS_ERR_DEV_INVALID_SEC_SIZE FS_ERR_DEV_INVALID_SIZE FS_ERR_DEV_INVALID_UNIT_NBR FS_ERR_DEV_IO FS_ERR_DEV_NONE_AVAIL FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_TIMEOUT FS_ERR_DEV_UNIT_NONE_AVAIL FS_ERR_DEV_UNIT_ALREADY_EXIST FS_ERR_DEV_UNKNOWN FS_ERR_DEV_VOL_OPEN FS_ERR_DEV_INCOMPATIBLE_LOW_PARAMS FS_ERR_DEV_INVALID_METADATA 394 Device access error. Device already open. Device has changed. Device is fixed (cannot be closed). Device is full (no space could be allocated). Invalid device. Invalid dev cfg. Invalid ECC. I/O control invalid. Low format invalid. Invalid low-level device parameters. Invalid mark. Invalid device name. Invalid operation. Invalid device sec nbr. Invalid device sec size. Invalid device size. Invalid device unit nbr. Device I/O error. No device avail. Device not open. Device not present. Device timeout. No unit avail. Unit already exists. Unknown. Vol open on dev. Incompatible low-level device parameters. Device driver metadata is invalid. 600-uC-FS-001.book Page 395 Wednesday, October 10, 2012 12:03 PM FS_ERR_DEV_OP_ABORTED FS_ERR_DEV_CORRUPT_LOW_FMT FS_ERR_DEV_INVALID_SEC_DATA FS_ERR_DEV_WR_PROT FS_ERR_DEV_OP_FAILED Operation aborted. Corrupted low-level fmt. Retrieved sec data is invalid. Device is write protected. Operation failed. FS_ERR_DEV_NAND_NO_AVAIL_BLK FS_ERR_DEV_NAND_NO_SUCH_SEC FS_ERR_DEV_NAND_ECC_NOT_SUPPORTED FS_ERR_DEV_NAND_ONFI_EXT_PARAM_PAGE No blk avail. This sector is not available. The needed ECC scheme is not supported. NAND device extended parameter page must be read. B-5 DEVICE DRIVER ERROR CODES FS_ERR_DEV_DRV_ALREADY_ADDED FS_ERR_DEV_DRV_INVALID_NAME FS_ERR_DEV_DRV_NONE_AVAIL Device driver already added. Invalid device driver name. No driver available. B-6 DIRECTORY ERROR CODES FS_ERR_DIR_ALREADY_OPEN FS_ERR_DIR_DIS FS_ERR_DIR_FULL FS_ERR_DIR_NONE_AVAIL FS_ERR_DIR_NOT_OPEN Directory already open. Directory module disabled. Directory is full. No directory avail. Directory not open. B-7 ECC ERROR CODES FS_ERR_ECC_CORRECTABLE FS_ERR_ECC_UNCORRECTABLE Correctable ECC error. Uncorrectable ECC error. B-8 ENTRY ERROR CODES FS_ERR_ENTRIES_SAME Paths specify same file system entry. 395 600-uC-FS-001.book Page 396 Wednesday, October 10, 2012 12:03 PM Appendix B FS_ERR_ENTRIES_TYPE_DIFF FS_ERR_ENTRIES_VOLS_DIFF FS_ERR_ENTRY_CORRUPT FS_ERR_ENTRY_EXISTS FS_ERR_ENTRY_INVALID FS_ERR_ENTRY_NOT_DIR FS_ERR_ENTRY_NOT_EMPTY FS_ERR_ENTRY_NOT_FILE FS_ERR_ENTRY_NOT_FOUND FS_ERR_ENTRY_PARENT_NOT_FOUND FS_ERR_ENTRY_PARENT_NOT_DIR FS_ERR_ENTRY_RD_ONLY FS_ERR_ENTRY_ROOT_DIR FS_ERR_ENTRY_TYPE_INVALID FS_ERR_ENTRY_OPEN Paths do not both specify files OR directories. Paths specify file system entries on different vols. File system entry is corrupt. File system entry exists. File system entry invalid. File system entry NOT a directory. File system entry NOT empty. File system entry NOT a file. File system entry NOT found. Entry parent NOT found. Entry parent NOT a directory. File system entry marked read-only. File system entry is a root directory. File system entry type is invalid. Operation not allowed on entry corresponding to an open file/dir. B-9 FILE ERROR CODES FS_ERR_FILE_ALREADY_OPEN FS_ERR_FILE_BUF_ALREADY_ASSIGNED FS_ERR_FILE_ERR FS_ERR_FILE_INVALID_ACCESS_MODE FS_ERR_FILE_INVALID_ATTRIB FS_ERR_FILE_INVALID_BUF_MODE FS_ERR_FILE_INVALID_BUF_SIZE FS_ERR_FILE_INVALID_DATE_TIME FS_ERR_FILE_INVALID_DATE_TIME_FLAG FS_ERR_FILE_INVALID_NAME FS_ERR_FILE_INVALID_ORIGIN FS_ERR_FILE_INVALID_OFFSET FS_ERR_FILE_INVALID_FILES FS_ERR_FILE_INVALID_OP FS_ERR_FILE_INVALID_OP_SEQ FS_ERR_FILE_INVALID_POS FS_ERR_FILE_LOCKED 396 File already open. Buf already assigned. Error indicator set on file. Access mode is specified invalid. Attributes are specified invalid. Buf mode is specified invalid or unknown. Buf size is specified invalid. Date/time is specified invalid. Date/time flag is specified invalid. Name is specified invalid. Origin is specified invalid or unknown. Offset is specified invalid. Invalid file arguments. File operation invalid. File operation sequence invalid. File position invalid. File locked. 600-uC-FS-001.book Page 397 Wednesday, October 10, 2012 12:03 PM FS_ERR_FILE_NONE_AVAIL FS_ERR_FILE_NOT_OPEN FS_ERR_FILE_NOT_LOCKED FS_ERR_FILE_OVF FS_ERR_FILE_OVF_OFFSET No file available. File NOT open. File NOT locked. File size overflowed max file size. File offset overflowed max file offset. B-10 NAME ERROR CODES FS_ERR_NAME_BASE_TOO_LONG FS_ERR_NAME_EMPTY FS_ERR_NAME_EXT_TOO_LONG FS_ERR_NAME_INVALID FS_ERR_NAME_MIXED_CASE FS_ERR_NAME_NULL FS_ERR_NAME_PATH_TOO_LONG FS_ERR_NAME_BUF_TOO_SHORT FS_ERR_NAME_TOO_LONG Base name too long. Name empty. Extension too long. Invalid file name or path. Name is mixed case. Name ptr arg(s) passed NULL ptr(s). Entry path is too long. Buffer for name is too short. Full name is too long. B-11 PARTITION ERROR CODES FS_ERR_PARTITION_INVALID FS_ERR_PARTITION_INVALID_NBR FS_ERR_PARTITION_INVALID_SIG FS_ERR_PARTITION_INVALID_SIZE FS_ERR_PARTITION_MAX FS_ERR_PARTITION_NOT_FINAL FS_ERR_PARTITION_NOT_FOUND FS_ERR_PARTITION_ZERO Partition invalid. Partition nbr specified invalid. Partition sig invalid. Partition size invalid. Max nbr partitions have been created in MBR. Prev partition is not final partition. Partition NOT found. Partition zero. B-12 POOLS ERROR CODES FS_ERR_POOL_EMPTY FS_ERR_POOL_FULL FS_ERR_POOL_INVALID_BLK_ADDR FS_ERR_POOL_INVALID_BLK_IN_POOL Pool is empty. Pool is full. Block not found in used pool pointers. Block found in free pool pointers. 397 600-uC-FS-001.book Page 398 Wednesday, October 10, 2012 12:03 PM Appendix B FS_ERR_POOL_INVALID_BLK_IX FS_ERR_POOL_INVALID_BLK_NBR FS_ERR_POOL_INVALID_BLK_SIZE Block index invalid. Number blocks specified invalid. Block size specified invalid. B-13 FILE SYSTEM ERROR CODES FS_ERR_SYS_TYPE_NOT_SUPPORTED FS_ERR_SYS_INVALID_SIG FS_ERR_SYS_DIR_ENTRY_PLACE FS_ERR_SYS_DIR_ENTRY_NOT_FOUND FS_ERR_SYS_DIR_ENTRY_NOT_FOUND_YET FS_ERR_SYS_SEC_NOT_FOUND FS_ERR_SYS_CLUS_CHAIN_END FS_ERR_SYS_CLUS_CHAIN_END_EARLY FS_ERR_SYS_CLUS_INVALID FS_ERR_SYS_CLUS_NOT_AVAIL FS_ERR_SYS_SFN_NOT_AVAIL FS_ERR_SYS_LFN_ORPHANED File sys type not supported. Sec has invalid OR illegal sig. Dir entry could not be placed. Dir entry not found. Dir entry not found (yet). Sec not found. Cluster chain ended. Cluster chain ended before number clusters traversed. Cluster invalid. Cluster not avail. SFN is not avail. LFN entry orphaned. B-14 VOLUME ERROR CODES FS_ERR_VOL_INVALID_NAME FS_ERR_VOL_INVALID_SIZE FS_ERR_VOL_INVALID_SEC_SIZE FS_ERR_VOL_INVALID_CLUS_SIZE FS_ERR_VOL_INVALID_OP FS_ERR_VOL_INVALID_SEC_NBR FS_ERR_VOL_INVALID_SYS FS_ERR_VOL_NO_CACHE FS_ERR_VOL_NONE_AVAIL FS_ERR_VOL_NONE_EXIST FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED FS_ERR_VOL_ALREADY_OPEN FS_ERR_VOL_FILES_OPEN 398 Invalid volume name. Invalid volume size. Invalid volume sector size. Invalid volume cluster size. Volume operation invalid. Invalid volume sector number. Invalid file system on volume. No cache assigned to volume. No vol avail. No vols exist. Vol NOT open. Vol NOT mounted. Vol already open. Files open on vol. 600-uC-FS-001.book Page 399 Wednesday, October 10, 2012 12:03 PM FS_ERR_VOL_DIRS_OPEN FS_ERR_JOURNAL_ALREADY_OPEN FS_ERR_JOURNAL_CFG_CHANGED FS_ERR_JOURNAL_FILE_INVALID FS_ERR_JOURNAL_FULL FS_ERR_JOURNAL_LOG_INVALID_ARG FS_ERR_JOURNAL_LOG_INCOMPLETE FS_ERR_JOURNAL_LOG_NOT_PRESENT FS_ERR_JOURNAL_NOT_OPEN FS_ERR_JOURNAL_NOT_REPLAYING FS_ERR_JOURNAL_NOT_STARTED FS_ERR_JOURNAL_NOT_STOPPED FS_ERR_VOL_LABEL_INVALID FS_ERR_VOL_LABEL_NOT_FOUND FS_ERR_VOL_LABEL_TOO_LONG Dirs open on vol. Journal already open. File system suite cfg changed since log created. Journal file invalid. Journal full. Invalid arg read from journal log. Log not completely entered in journal. Log not present in journal. Journal not open Journal not being replayed. Journaling not started. Journaling not stopped. Volume label is invalid. Volume label was not found. Volume label is too long. B-15 OS LAYER ERROR CODES FS_ERR_OS_LOCK FS_ERR_OS_INIT FS_ERR_OS_INIT_LOCK FS_ERR_OS_INIT_LOCK_NAME Lock not acquired. OS not initialized. Lock signal not successfully initialized. Lock signal name not successfully initialized. 399 600-uC-FS-001.book Page 400 Wednesday, October 10, 2012 12:03 PM Appendix B 400 600-uC-FS-001.book Page 401 Wednesday, October 10, 2012 12:03 PM Appendix C C/FS Porting Manual C/FS adapts to its environment via a number of ports. The simplest ones, common to all installations, interface with the application, OS kernel (if any) and CPU. More complicated may be ports to media drivers, which require additional testing, validation and optimization; but many of those are still straightforward. Figure C-1 diagrams the relationship between C/FS and external modules and hardware. The sections in this chapter describe each require function and give hints for implementers. Anyone creating a new port should first check the example ports are included in the C/FS distribution in the following directory: \Micrium\Software\uC-FS\Examples\BSP\Dev The port being contemplated may already exist; failing that, some similar CPU/device may have already be supported. 401 600-uC-FS-001.book Page 402 Wednesday, October 10, 2012 12:03 PM Appendix C (1) (2) C/FS Platform Independent (3) Clk CPU RTOS C/FS Drivers (4) SD/MMC Driver (5) (6) SD/MMC Host Controller NAND Driver (7) (8) NAND Device NOR Driver (9) (10) (11) NOR Device Figure C-1 C/FS ports architecture FC-1(1) C/Clk act as a centralized clock management module. If you use an external real-time clock, you will have to write functions to let C/FS know the date and time. FC-1(2) The CPU port (within C/CPU) adapts the file system suite to the CPU and compiler characteristics. The fixed-width types (e.g., CPU_INT16U) used in the file system suite are defined here. FC-1(3) The RTOS port adapts the file system suite to the OS kernel (if any) included in the application. The files FS_OS.C/H contain functions primarily aimed at making accesses to devices and critical information in memory thread-safe. FC-1(4) C/FS interfaces with memory devices through drivers following a generic driver model. It is possible to create a driver for a different type of device from this model/template. FC-1(5) The SD/MMC driver can be ported to any SD/MMC host controller for cardmode access. 402 600-uC-FS-001.book Page 403 Wednesday, October 10, 2012 12:03 PM FC-1(6) The SD/MMC driver can be ported to any SPI peripheral for SPI mode access. FC-1(7) The NAND driver can be ported for many physical organizations (page size, bus width, SLC/MLC, etc.). FC-1(8) The NAND driver can be ported to any bus interface. A NAND device can also be located directly on GPIO and accessed by direct toggling of port pins. FC-1(9) The NOR driver can be ported to many physical organization (command set, bus type, etc.). FC-1(10) The NOR driver can be ported to any bus interface. FC-1(11) The NOR driver can be ported to any SPI peripheral (for SPI flash). C-1 DATE/TIME MANAGEMENT Depending on the settings of C/Clk, you might have to write time management functions that are specific to your application. For example, you might have to define the function Clk_ExtTS_Get() to obtain the timestamp of your system provided by a real-time clock peripheral. Please refer to C/Clk manual for more details. C-2 CPU PORT C/CPU is a processor/compiler port needed for C/FS to be CPU/compiler-independant. Ports for the most popular architectures are already available in the C/CPU distribution. If the C/CPU port for your target architecture is not available, you should create your own based on the port template (also available in C/CPU distribution). You should refer to the C/CPU user manual to know how you should use it in your project. 403 600-uC-FS-001.book Page 404 Wednesday, October 10, 2012 12:03 PM Appendix C C-3 OS KERNEL C/FS can be used with or without an RTOS. Either way, an OS port must be included in your project. The port includes one code/header file pair: fs_os.c fs_os.h C/FS manages devices and data structures that may not be accessed by severally tasks simultaneously. An OS kernel port leverages the kernel's mutual exclusion services (mutexes) for that purpose. These files are generally placed in a directory named according to the following rubric: \Micrium\Software\uC-FS\OS\<os_name> Four sets of files are included with the C/FS distribution: \Micrium\Software\uC-FS\OS\Template \Micrium\Software\uC-FS\OS\None \Micrium\Software\uC-FS\OS\uCOS-II \Micrium\Software\uC-FS\OS\uCOS-III Template No OS kernel port C/OS-II port C/OS-III port If you don't use any OS (including a custom in-house OS), you should include the port for no OS in your project. You must also make sure that you manage interrupts correctly. If you are using C/OS-II or C/OS-III, you should include the appropriate ports in your project. If you use another OS, you should create your own port based on the template. The functions that need to be written in this port are described here. FS_OS_Init(), FS_OS_Lock() and FS_OS_Unlock() The core data structures are protected by a single mutex. FS_OS_Init() creates this semaphore. FS_OS_Lock() and FS_OS_Unlock() acquire and release the resource. Lock operations are never nested. 404 600-uC-FS-001.book Page 405 Wednesday, October 10, 2012 12:03 PM FS_OS_DevInit(), FS_OS_DevLock() and FS_OS_DevUnlock() File system device, generally, do not tolerate multiple simultaneous accesses. A different mutex controls access to each device and information about it in RAM. FS_OS_DevInit() creates one mutex for each possible device. FS_OS_DevLock() and FS_OS_DevUnlock() acquire and release access to a specific device. Lock operations for the same device are never nested. FS_OS_FileInit(), FS_OS_FileAccept(), FS_OS_FileLock() and FS_OS_FileUnlock() Multiple calls to file access functions may be required for a file operation that must be guaranteed atomic. For example, a file may be a conduit of data from one task to several. If a data entry cannot be read in a single file read, some lock is necessary to prevent preemption by another consumer. File locks, represented by API functions like FSFile_LockGet() and flockfile(), provide a solution. Four functions implement the actual lock in the OS port. FS_OS_FileInit() creates one mutex for each possible file. FS_OS_FileLock()/ FS_OS_FileAccept() and FS_OS_FileUnlock() acquire and release access to a specific file. Lock operations for the same file MAY be nested, so the implementations must be able to determine whether the active task owns the mutex. If it does, then an associated lock count should be incremented; otherwise, it should try to acquire the resource as normal. FS_OS_WorkingDirGet() and FS_OS_WorkingDirSet() File and directory paths are typically interpreted absolutely; they must start at the root directory, specifying every intermediate path component. If much work will be accomplished upon files in a certain directory or a task requires a root directory as part of its context, working directories are valuable. Once a working directory is set for a task, subsequent non-absolute paths will be interpreted relative to the set directory. 405 600-uC-FS-001.book Page 406 Wednesday, October 10, 2012 12:03 PM Appendix C #if (FS_CFG_WORKING_DIR_EN == DEF_ENABLED) CPU_CHAR *FS_OS_WorkingDirGet (void) { OS_ERR CPU_INT32U CPU_CHAR (1) os_err; reg_val; *p_working_dir; reg_val = OSTaskRegGet((OS_TCB *) 0, FS_OS_REG_ID_WORKING_DIR, &os_err); if (os_err != OS_ERR_NONE) { reg_val = 0u; } p_working_dir = (CPU_CHAR *)reg_val; return (p_working_dir); } #endif #if (FS_CFG_WORKING_DIR_EN == DEF_ENABLED) void FS_OS_WorkingDirSet (CPU_CHAR *p_working_dir, FS_ERR *p_err) { OS_ERR os_err; CPU_INT32U reg_val; reg_val = (CPU_INT32U)p_working_dir; OSTaskRegSet((OS_TCB *) 0, FS_OS_RegIdWorkingDir, (OS_REG) reg_val, &os_err); if(os_err != OS_ERR_NONE) { *p_err = FS_ERR_OS; return; } *p_err = FS_ERR_NONE; } #endif Listing C-1 FS_OS_WorkingDirGet()/Set() (C/OS-III) LC-1(1) 406 FS_OS_WorkingDirGet() gets the pointer to the working directory associated with the active task. In C/OS-III, the pointer is stored in one of the task registers, a set of software data that is part of the task context (just like hardware register values). The implantation casts the integral register value to a pointer to a character. If no working directory has been assigned, the return value must be a pointer to NULL. In the case of C/OS-III, that will be done because the register values are cleared upon task creation. 600-uC-FS-001.book Page 407 Wednesday, October 10, 2012 12:03 PM LC-1(2) FS_OS_WorkingDirSet() associates a working directory with the active task. The pointer is cast to the integral register data type and stored in a task register. The application calls either of the core file system functions FS_WorkingDirSet() or fs_chdir() to set the working directory. The core function forms the full path of the working directory and "saves" it with the OS port function FS_OS_WorkingDirSet(). The port function should associate it with the task in some manner so that it can be retrieved with FS_OS_WorkingDirGet() even after many context switches have occurred. #if (FS_CFG_WORKING_DIR_EN == DEF_ENABLED) void FS_OS_WorkingDirFree (OS_TCB *p_tcb) { OS_ERR os_err; CPU_INT32U reg_val; CPU_CHAR *path_buf; reg_val = OSTaskRegGet( p_tcb, FS_OS_REG_ID_WORKING_DIR, &os_err); if (os_err != OS_ERR_NONE) { return; } if (reg_val == 0u) { return; } path_buf = (CPU_CHAR *)reg_val; FS_WorkingDirObjFree(path_buf); } #endif (1) (2) Listing C-2 FS_OS_WorkingDirFree() (C/OS-III) LC-2(1) If the register value is zero, no working directory has been assigned and no action need be taken. LC-2(2) FS_WorkingDirObjFree() frees the working directory object to the working directory pool. If this were not done, the unfreed object would constitute a memory leak that could deplete the heap memory eventually. 407 600-uC-FS-001.book Page 408 Wednesday, October 10, 2012 12:03 PM Appendix C The character string for the working directory is allocated from the C/LIB heap. If a task is deleted, it must be freed (made available for future allocation) to avert a crippling memory leak. The internal file system function FS_WorkingDirObjFree() releases the string to an object pool. In the port for C/OS-III, that function is called by FS_OS_WorkingDirFree() which must be called by the assigned task delete hook. FS_OS_Dly_ms() Device drivers and example device driver ports delay task execution FS_OS_Dly_ms(). Common functions allow BSP developers to optimize implementation easily. A millisecond delay may be accomplished with an OS kernel service, if available. The trivial implementation of a delay (particularly a sub-millisecond delay) is a while loop; better performance may be achieved with hardware timers with semaphores for wait and asynchronous notification. The best solution will vary from one platform to another, since the additional context switches may prove burdensome. No matter which strategy is selected, the function MUST delay for at least the specified time amount; otherwise, sporadic errors can occur. Ideally, the actual time delay will equal the specified time amount to avoid wasting processor cycles. void FS_BSP_Dly_ms (CPU_INT16U ms) { /* $$$$ Insert code to delay for specified number of millieconds. */ } Listing C-3 FS_OS_Dly_ms() FS_OS_Sem####() The four generic OS semaphore functions provide a complete abstraction of a basic OS kernel service. FS_OS_SemCreate() creates a semaphore which may later be deleted with FS_OS_SemDel(). FS_OS_SemPost() signals the semaphore (with or without timeout) and FS_OS_SemPend() waits until the semaphore is signaled. On systems without an OS kernel, the trivial implementations in Listing C-4 are recommended. 408 600-uC-FS-001.book Page 409 Wednesday, October 10, 2012 12:03 PM CPU_BOOLEAN FS_OS_SemCreate (FS_BSP_SEM CPU_INT16U *p_sem, cnt) (1) { *p_sem = cnt; return (DEF_OK); /* $$$$ Create semaphore with initial count 'cnt'. */ } CPU_BOOLEAN FS_OS_SemDel (FS_BSP_SEM *p_sem) { *p_sem = 0u; /* $$$$ Delete semaphore. */ (2) return (DEF_OK); } Listing C-4 FS_OS_Sem####() trivial implementations 409 600-uC-FS-001.book Page 410 Wednesday, October 10, 2012 12:03 PM Appendix C CPU_BOOLEAN FS_OS_SemPend (FS_BSP_SEM CPU_INT32U *p_sem, timeout) (3) { CPU_INT32U timeout_cnts; CPU_INT16U sem_val; CPU_SR_ALLOC(); if (timeout == 0u) { sem_val = 0u; while (sem_val == 0u) { CPU_CRITICAL_ENTER(); sem_val = *p_sem; if (sem_val > 0u) { *p_sem = sem_val - 1u; } CPU_CRITICAL_EXIT(); /* $$$$ If semaphore available ... */ /* */ ... decrement semaphore count. } } else { timeout_cnts = timeout * FS_BSP_CNTS_PER_MS; sem_val = 0; while ((timeout_cnts > 0u) && (sem_val == 0u)) { CPU_CRITICAL_ENTER(); sem_val = *p_sem; if (sem_val > 0) { *p_sem = sem_val - 1u; } CPU_CRITICAL_EXIT(); timeout_cnts--; } /* $$$$ If semaphore available ... */ /* */ ... decrement semaphore count. } if (sem_val == 0u) { return (DEF_FAIL); } else { return (DEF_OK); } } Listing C-5 FS_OS_Sem####() trivial implementations (continued) LC-5(1) FS_OS_SemCreate() creates a semaphore in the variable p_sem. For this trivial implementation, FS_BSP_SEM is a integer type which stores the current count, i.e., the number of objects available. LC-5(2) FS_OS_SemDel() deletes a semaphore created by FS_OS_SemCreate(). 410 600-uC-FS-001.book Page 411 Wednesday, October 10, 2012 12:03 PM CPU_BOOLEAN FS_OS_SemPost (FS_BSP_SEM *p_sem) { CPU_INT16U sem_val; CPU_SR_ALLOC(); CPU_CRITICAL_ENTER(); sem_val = *p_sem; /* $$$$ Increment semaphore value. */ sem_val++; *p_sem = sem_val; CPU_CRITICAL_EXIT(); return (DEF_OK); } (4) Listing C-6 FS_OS_Sem####() trivial implementations (continued) LC-6(3) FS_OS_SemPend() waits until a semaphore is signaled. If a zero timeout is given, the wait is possibly infinite (it never times out). LC-6(4) FS_OS_SemPost() signals a semaphore. 411 600-uC-FS-001.book Page 412 Wednesday, October 10, 2012 12:03 PM Appendix C C-4 DEVICE DRIVER Devices drivers for the most popular devices are already available for C/FS. If you use a particular device for which no driver exist, you should read this section to understand how to build your own driver. A device driver is registered with the file system by passing a pointer to its API structure as the first parameter of FS_DevDrvAdd(). The API structure, FS_DEV_API, includes pointers to eight functions used to control and access the device: const FS_DEV_API FSDev_#### = { FSDev_####_NameGet, FSDev_####_Init, FSDev_####_Open, FSDev_####_Close, FSDev_####_Rd, #if (FS_CFG_RD_ONLY_EN == DEF_DISABLED) FSDev_####_Wr, #endif FSDev_####_Query, FSDev_####_IO_Ctrl }; The functions which must be implemented are listed and described in Table C-1. The first two functions, NameGet() and Init(), act upon the driver as a whole; neither should interact with any physical devices. The remaining functions act upon individual devices, and the first argument of each is a pointer to a FS_DEV structure which holds device information, including the unit number which uniquely identifies the device unit (member UnitNbr). 412 600-uC-FS-001.book Page 413 Wednesday, October 10, 2012 12:03 PM Function Description NameGet() Get driver name. Init() Initialize driver. Open() Open a device. Close() Close a device. Rd() Read from a device. Wr() Write to a device. Query() Get information about a device. IO_Ctrl() Execute device I/O control operation. Table C-1 Device driver API functions 413 600-uC-FS-001.book Page 414 Wednesday, October 10, 2012 12:03 PM Appendix C C-4-1 NameGet() static const CPU_CHAR *FSDev_####_NameGet (void); File Called from Code enabled by fs_dev_####.c various N/A Device drivers are identified by unique names, on which device names are based. For example, the unique name for the NAND flash driver is "nand"; the NAND devices will be named "nand:0:", "nand:1:", etc. ARGUMENTS None. RETURNED VALUE Pointer to the device driver name. NOTES/WARNINGS 1 The name must not include the `:' character. 2 The name must be constant; each time this function is called, the same name MUST be returned. 3 The device driver NameGet() function is called while the caller holds the FS lock. 414 600-uC-FS-001.book Page 415 Wednesday, October 10, 2012 12:03 PM C-4-2 Init() static void FSDev_####_Init (void); File Called from Code enabled by fs_dev_####.c FS_DevDrvAdd() N/A The device driver Init() function should initialize any structures, tables or variables that are common to all devices or are used to manage devices accessed with the driver. This function should not initialize any devices; that will be done individually for each with the device driver's Open() function. ARGUMENTS None. RETURNED VALUE None. NOTES/WARNINGS 1 The device driver Init() function is called while the caller holds the FS lock. 415 600-uC-FS-001.book Page 416 Wednesday, October 10, 2012 12:03 PM Appendix C C-4-3 Open() static void FSDev_####_Open (FS_DEV *p_dev, void *p_dev_cfg, FS_ERR *p_err); File Called from Code enabled by fs_dev_####.c FSDev_Open() N/A The device driver Open() function should initialize the hardware to access a device and attempt to initialize that device. If this function is successful (i.e., it returns FS_ERR_NONE), then the file system suite expects the device to be ready for read and write accesses. ARGUMENTS p_dev Pointer to device to open. p_dev_cfg Pointer to device configuration. p_err Pointer to variable that will receive the return error code from this function: FS_ERR_NONE FS_ERR_DEV_ALREADY_OPEN FS_ERR_DEV_INVALID_CFG FS_ERR_DEV_INVALID_LOW_FMT FS_ERR_DEV_INVALID_LOW_PARAMS Device opened successfully. Device unit is already opened. Device configuration specified invalid. Device needs to be low-level formatted. Device low-level device parameters invalid. FS_ERR_DEV_INVALID_UNIT_NBR Device unit number is invalid. FS_ERR_DEV_IO Device I/O error. FS_ERR_DEV_NOT_PRESENT Device unit is not present. FS_ERR_DEV_TIMEOUT Device timeout. FS_ERR_MEM_ALLOC Memory could not be allocated. RETURNED VALUE None. 416 600-uC-FS-001.book Page 417 Wednesday, October 10, 2012 12:03 PM NOTES/WARNINGS 1 Tracking whether a device is open is not necessary, because this should NEVER be called when a device is already open. 2 Some drivers may need to track whether a device has been previously opened (indicating that the hardware has previously been initialized). 3 This will be called every time the device is opened. 4 The driver should identify the device instance to be opened by checking p_dev->UnitNbr. For example, if "template:2:" is to be opened, then p_dev->UnitNbr will hold the integer 2. 5 The device driver Open() function is called while the caller holds the device lock. 417 600-uC-FS-001.book Page 418 Wednesday, October 10, 2012 12:03 PM Appendix C C-4-4 Close() static void FSDev_####_Close (FS_DEV *p_dev); File Called from Code enabled by fs_dev_####.c FSDev_Close() N/A The device driver Close() function should uninitialize the hardware and release or free any resources acquired in the Open() function. ARGUMENTS p_dev Pointer to device to close. RETURNED VALUE None. NOTES/WARNINGS 1 Tracking whether a device is open is not necessary, because this should ONLY be called when a device is open. 2 This will be called EVERY time the device is closed. 3 The device driver Close() function is called while the caller holds the device lock. 418 600-uC-FS-001.book Page 419 Wednesday, October 10, 2012 12:03 PM C-4-5 Rd() static void FSDev_####_Rd (FS_DEV *p_dev, void *p_dest, FS_SEC_NBR start, FS_SEC_QTY cnt, FS_ERR *p_err); File Called from Code enabled by fs_dev_####.c FSDev_RdLocked() N/A The device driver Rd() function should read from a device and store data in a buffer. If an error is returned, the file system suite assumes that no data is read; if not all data can be read, an error MUST be returned. ARGUMENTS p_dev Pointer to device to read from. p_dest Pointer to destination buffer. start Start sector of read. cnt Number of sectors to read p_err Pointer to variable that will receive the return error code from this function FS_ERR_NONE FS_ERR_DEV_INVALID_UNIT_NBR FS_ERR_DEV_IO FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_TIMEOUT Sector(s) read. Device unit number is invalid. Device I/O error. Device is not open. Device is not present. Device timeout. 419 600-uC-FS-001.book Page 420 Wednesday, October 10, 2012 12:03 PM Appendix C RETURNED VALUE None. NOTES/WARNINGS 1 Tracking whether a device is open is not necessary, because this should only be called when a device is open. 2 The device driver Rd() function is called while the caller holds the device lock. 420 600-uC-FS-001.book Page 421 Wednesday, October 10, 2012 12:03 PM C-4-6 Wr() static void FSDev_####_Wr (FS_DEV *p_dev, void *p_src, FS_SEC_NBR start, FS_SEC_QTY cnt, FS_ERR *p_err); File Called from Code enabled by fs_dev_####.c FSDev_WrLocked() N/A The device driver Wr() function should write to a device the data from a buffer. If an error is returned, the file system suite assumes that no data has been written. ARGUMENTS p_dev Pointer to device to write to. p_src Pointer to source buffer. start Start sector of write. cnt Number of sectors to write p_err Pointer to variable that will receive the return error code from this function FS_ERR_NONE FS_ERR_DEV_INVALID_UNIT_NBR FS_ERR_DEV_IO FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_TIMEOUT Sector(s) written. Device unit number is invalid. Device I/O error. Device is not open. Device is not present. Device timeout. 421 600-uC-FS-001.book Page 422 Wednesday, October 10, 2012 12:03 PM Appendix C RETURNED VALUE None. NOTES/WARNINGS 1 Tracking whether a device is open is not necessary, because this should only be called when a device is open. 2 The device driver Wr() function is called while the caller holds the device lock. 422 600-uC-FS-001.book Page 423 Wednesday, October 10, 2012 12:03 PM C-4-7 Query() static void FSDev_####_Query (FS_DEV *p_dev, FS_DEV_INFO *p_info, FS_ERR *p_err); File Called from Code enabled by fs_dev_####.c FSDev_Open(), FSDev_Refresh(), FSDev_QueryLocked() N/A The device driver Query() function gets information about a device. ARGUMENTS p_dev Pointer to device to query. p_info Pointer to structure that will receive device information. p_err Pointer to variable that will receive the return error code from this function FS_ERR_NONE FS_ERR_DEV_INVALID_UNIT_NBR FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT Device Device Device Device information obtained. unit number is invalid. is not open. is not present. RETURNED VALUE None. NOTES/WARNINGS 1 Tracking whether a device is open is not necessary, because this should ONLY be called when a device is open. 2 The device driver Query() function is called while the caller holds the device lock. For more information about the FS_DEV_INFO structure, see section D-2 "FS_DEV_INFO" on page 484. 423 600-uC-FS-001.book Page 424 Wednesday, October 10, 2012 12:03 PM Appendix C C-4-8 IO_Ctrl() static void FSDev_####_IO_Ctrl (FS_DEV *p_dev, FS_IO_CTRL_CMD cmd, Void *p_buf, FS_ERR *p_err); File Called from Code enabled by fs_dev_####.c various N/A The device driver IO_Ctrl() function performs an I/O control operation. ARGUMENTS p_dev Pointer to device to query. p_buf Buffer which holds data to be used for operations OR Buffer in which data will be stored as a result of operation. p_err Pointer to variable that will receive the return error code from this function FS_ERR_NONE Control operation performed successfully. FS_ERR_DEV_INVALID_IO_CTRL I/O control operation unknown to driver. FS_ERR_DEV_INVALID_UNIT_NBR Device unit number is invalid. FS_ERR_DEV_IO Device I/O error. FS_ERR_DEV_NOT_OPEN Device is not open. FS_ERR_DEV_NOT_PRESENT Device is not present. FS_ERR_DEV_TIMEOUT Device timeout. RETURNED VALUE None. 424 600-uC-FS-001.book Page 425 Wednesday, October 10, 2012 12:03 PM NOTES/WARNINGS 1 Tracking whether a device is open is not necessary, because this should ONLY be called when a device is open. 2 Defined I/O control operations are a. b. c. d. e. f. g. h. i. j. k. l. m. FS_DEV_IO_CTRL_REFRESH FS_DEV_IO_CTRL_LOW_FMT FS_DEV_IO_CTRL_LOW_MOUNT FS_DEV_IO_CTRL_LOW_UNMOUNT FS_DEV_IO_CTRL_LOW_COMPACT FS_DEV_IO_CTRL_LOW_DEFRAH FS_DEV_IO_CTRL_SEC_RELEASE FS_DEV_IO_CTRL_PHY_RD FS_DEV_IO_CTRL_PHY_WR FS_DEV_IO_CTRL_PHY_RD_PAGE FS_DEV_IO_CTRL_PHY_WR_PAGE FS_DEV_IO_CTRL_PHY_ERASE_BLK FS_DEV_IO_CTRL_PHY_ERASE_CHIP Refresh device. Low-level format device. Low-level mount device. Low-level unmount device. Low-level compact device. Low-level defragment device. Release data in sector Read physical device Write physical device Read physical device page Write physical device page Erase physical device block Erase physical device Not all of these operations are valid for all devices. The device driver IO_Ctrl() function is called while the caller holds the device lock. C-5 SD/MMC CARDMODE BSP The SD/MMC cardmode protocol is unique to SD- and MMC-compliant devices. The generic driver handles the peculiarities for initializing, reading and writing a card (including state transitions and error handling), but each CPU has a different host controller that must be individually ported. To that end, a BSP, supplementary to the general C/FS BSP, is required that abstracts the SD/MMC interface. The port includes one code file: FS_DEV_SD_CARD_BSP.C This file is generally placed with other BSP files in a directory named according to the following rubric: 425 600-uC-FS-001.book Page 426 Wednesday, October 10, 2012 12:03 PM Appendix C \Micrium\Software\EvalBoards\<manufacturer>\<board_name> \<compiler>\BSP\ Several example ports are included in the C/FS distribution in files named according to the following rubric: \Micrium\Software\uC-FS\Examples\BSP\Dev\SD\Card\<cpu_name> Function Description FSDev_SD_Card_BSP_Open() Open (initialize) SD/MMC card interface. FSDev_SD_Card_BSP_Close() Close (uninitialize) SD/MMC card interface. FSDev_SD_Card_BSP_Lock() Acquire SD/MMC card bus lock. FSDev_SD_Card_BSP_Unlock() Release SD/MMC card bus lock. FSDev_SD_Card_BSP_CmdStart() Start a command. FSDev_SD_Card_BSP_CmdWaitEnd() Wait for a command to end and get response. FSDev_SD_Card_BSP_CmdDataRd() Read data following command. FSDev_SD_Card_BSP_CmdDataWr() Write data following command. FSDev_SD_Card_BSP_GetBlkCntMax() Get max block count. FSDev_SD_Card_BSP_GetBusWidthMax() Get maximum bus width, in bits. FSDev_SD_Card_BSP_SetBusWidth() Set bus width. FSDev_SD_Card_BSP_SetClkFreq() Set clock frequency. FSDev_SD_Card_BSP_SetTimeoutData() Set data timeout. FSDev_SD_Card_BSP_SetTimeoutResp() Set response timeout. Table C-2 SD/MMC cardmode BSP functions Each BSP must implement the functions in Table C-2. (For information about creating a port for a platform accessing a SD/MMC device in SPI mode, see section C-6 "SD/MMC SPI mode BSP" on page 452) This software interface was designed by reviewing common host implementations as well as the SD card association's SD Specification Part A2 - SD Host Controller Simplified Specification, Version 2.00, which recommends a host architecture and provides the state machines that would guide operations. Example function implementations for a theoretical compliant host are provided in this chapter. Common 426 600-uC-FS-001.book Page 427 Wednesday, October 10, 2012 12:03 PM advanced requirements (such as multiple cards per slot) and optimizations (such as DMA) are possible. No attempt has been made, however, to accommodate non-storage devices that are accessed on a SD/MMC cardmode, including SDIO devices. The core operation being abstracted is the command/response sequence for high-level card transactions. The key functions, CmdStart(), CmdWaitEnd(), CmdDataRd() and CmdDataWr(), are called within the state machine of Figure C-2. If return error from one of the functions will abort the state machine, so the requisite considerations, such as preparing for the next command or preventing further interrupts, must be handled if an operation cannot be completed. Start command execution FSDev_SD_Card_BSP_CmdStart() Wait for command to execute and response to be returned FSDev_SD_Card_BSP_CmdWaitEnd() Write Data? FSDev_SD_Card_BSP_CmdDataWr() Error returned Return Error returned Return Read FSDev_SD_Card_BSP_CmdDataRd() Return Figure C-2 Command execution The remaining functions either investigate host capabilities (GetBlkCntMax(), GetBusWidthMax()) or set operational parameters (SetBusWidth(), SetClkFreq(), SetTimeoutData(), SetTimeoutResp()). Together, these function sets help configure a new card upon insertion. Note that the parameters configured by the `set' functions belong to the card, not the slot; if multiple cards may be multiplexed in a single slot, these must be saved when set and restored whenever Lock() is called. 427 600-uC-FS-001.book Page 428 Wednesday, October 10, 2012 12:03 PM Appendix C Two elements of host behavior routinely influence implementation and require design choices. First, block data can typically be read/written either directly from a FIFO or transferred automatically by the peripheral to/from a memory buffer with DMA. While the former approach may be simpler--no DMA controller need be setup--it may not be reliable. Unless the host can stop the host clock upon FIFO underrun (for write) or overrun (for read), effectively pausing the operation from the card's perspective, transfers at high clock frequency or multiple-bus configurations will probably fail. Interrupts or other tasks can interrupt the operation, or the CPU just may be unable to fill the FIFO fast enough. DMA avoids those pitfalls by offloading the responsibility for moving data directly to the CPU. Second, the completion of operations such as command execution and data read/write are often signaled via interrupts (unless some error occurs, whereupon a different interrupt is triggered). During large transfers, these operations occur frequently and the typical wait between initiation and completion is measured in microseconds. On most platforms, polling the interrupt status register within the task performs better (i.e., results in faster reads and writes) than waiting on a semaphore for an asynchronous notification from the ISR, because the penalty of extra context switches is not incurred. 428 600-uC-FS-001.book Page 429 Wednesday, October 10, 2012 12:03 PM C-5-1 FSDev_SD_Card_BSP_Open() CPU_BOOLEAN FSDev_SD_Card_BSP_Open (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_sd_card_bsp.c FSDev_SD_Card_Refresh() N/A Open (initialize) SD/MMC card interface. ARGUMENTS unit_nbr Unit number of SD/MMC card. RETURNED VALUE DEF_OK, if interface was opened. DEF_FAIL, otherwise. NOTES/WARNINGS This function will be called EVERY time the device is opened. 429 600-uC-FS-001.book Page 430 Wednesday, October 10, 2012 12:03 PM Appendix C C-5-2 FSDev_SD_Card_BSP_Lock/Unlock() void FSDev_SD_Card_BSP_Lock (FS_QTY unit_nbr); void FSDev_SD_Card_BSP_Unlock (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_sd_card_bsp.c SD/MMC cardmode driver N/A Acquire/release SD/MMC card bus lock. ARGUMENTS unit_nbr Unit number of SD/MMC card. RETURNED VALUE None. NOTES/WARNINGS FSDev_SD_Card_BSP_Lock() will be called before the driver begins to access the SD/MMC card bus. The application should NOT use the same bus to access another device until the matching call to FSDev_SD_Card_BSP_Unlock() has been made. The clock frequency, bus width and timeouts set by the FSDev_SD_Card_BSP_Set####() functions are parameters of the card, not the bus. If multiple cards are located on the same bus, those parameters must be saved (in memory) when set and restored when FSDev_SD_Card_BSP_Lock() is called. 430 600-uC-FS-001.book Page 431 Wednesday, October 10, 2012 12:03 PM C-5-3 FSDev_SD_Card_BSP_CmdStart() void FSDev_SD_Card_BSP_CmdStart (FS_QTY unit_nbr, FS_DEV_SD_CARD_CMD *p_cmd, void *p_data, FS_DEV_SD_CARD_ERR *p_err); File Called from Code enabled by fs_dev_sd_card_bsp.c SD/MMC cardmode driver N/A Start a command. ARGUMENTS unit_nbr Unit number of SD/MMC card. p_cmd Pointer to command to transmit (see Note #2). p_data Pointer to buffer address for DMA transfer (see Note #3). p_err Pointer to variable that will receive the return error code from this function: FS_DEV_SD_CARD_ERR_NONE FS_DEV_SD_CARD_ERR_NO_CARD FS_DEV_SD_CARD_ERR_BUSY FS_DEV_SD_CARD_ERR_UNKNOWN No error. No card present. Controller is busy. Unknown or other error. RETURNED VALUE None. NOTES/WARNINGS 1 The command start will be followed by zero, one or two additional BSP function calls, depending on whether data should be transferred and on whether any errors occur. a. FSDev_SD_Card_BSP_CmdStart() starts execution of the command. IT may also set up the DMA transfer (if necessary). 431 600-uC-FS-001.book Page 432 Wednesday, October 10, 2012 12:03 PM Appendix C b. FSDev_SD_Card_BSP_CmdWaitEnd() waits for the execution of the command to end, getting the command response (if any). c. If data should transferred from the card to the host, FSDev_SD_Card_BSP_CmdDataRd() will read that data; if data should be transferred from the host to the card, FSDev_SD_Card_BSP_CmdDataWr() will write that data. 2 The command p_cmd has the following parameters: p_cmd->Cmd is the command index. p_cmd->Arg is the 32-bit argument (or 0 if there is no argument). p_cmd->Flags is a bit-mapped variable with zero or more command flags: FS_DEV_SD_CARD_CMD_FLAG_INIT FS_DEV_SD_CARD_CMD_FLAG_BUSY FS_DEV_SD_CARD_CMD_FLAG_CRC_VALID FS_DEV_SD_CARD_CMD_FLAG_IX_VALID FS_DEV_SD_CARD_CMD_FLAG_OPEN_DRAIN FS_DEV_SD_CARD_CMD_FLAG_DATA_START FS_DEV_SD_CARD_CMD_FLAG_DATA_STOP FS_DEV_SD_CARD_CMD_FLAG_RESP FS_DEV_SD_CARD_CMD_FLAG_RESP_LONG p_cmd->DataDir indicates the direction of any data transfer that should follow this command, if any: FS_DEV_SD_CARD_DATA_DIR_NONE FS_DEV_SD_CARD_DATA_DIR_HOST_TO_CARD FS_DEV_SD_CARD_DATA_DIR_CARD_TO_HOST 432 Initialization sequence before command. Busy signal expected after command. CRC valid after command. Index valid after command. Command line is open drain. Data start command. Data stop command. Response expected. Long response expected. No data transfer. Transfer host-to-card (write). Transfer card-to-host (read). 600-uC-FS-001.book Page 433 Wednesday, October 10, 2012 12:03 PM p_cmd->DataType indicates the type of the data transfer that should follow this command, if any: FS_DEV_SD_CARD_DATA_TYPE_NONE FS_DEV_SD_CARD_DATA_TYPE_SINGLE_BLOCK FS_DEV_SD_CARD_DATA_TYPE_MULTI_BLOCK FS_DEV_SD_CARD_DATA_TYPE_STREAM p_cmd->RespType indicates the type of the response that should be expected from this command: FS_DEV_SD_CARD_RESP_TYPE_NONE FS_DEV_SD_CARD_RESP_TYPE_R1 FS_DEV_SD_CARD_RESP_TYPE_R1B FS_DEV_SD_CARD_RESP_TYPE_R2 FS_DEV_SD_CARD_RESP_TYPE_R3 FS_DEV_SD_CARD_RESP_TYPE_R4 FS_DEV_SD_CARD_RESP_TYPE_R5 FS_DEV_SD_CARD_RESP_TYPE_R5B FS_DEV_SD_CARD_RESP_TYPE_R6 FS_DEV_SD_CARD_RESP_TYPE_R7 3 No data transfer. Single data block. Multiple data blocks. Stream data. No response. R1 response: Normal Response Command. R1b response. R2 response: CID, CSD Register. R3 response: OCR Register. R4 response: Fast I/O Response (MMC). R5 response: Interrupt Request Response (MMC). R5B response. R6 response: Published RCA Response. R7 response: Card Interface Condition. p_cmd->BlkSize and p_cmd->BlkCnt are the block size and block count of the data transfer that should follow this command, if any. The pointer to the data buffer that will receive the data transfer that should follow this command, p_data, is given so that a DMA transfer can be set up. EXAMPLE The example implementation of FSDev_SD_Card_BSP_CmdStart() in , like the examples in subsequent sections, targets a generic host conformant to the SD card association's host controller specification. While few hosts do conform, most have a similar mixture of registers and registers fields and require the same sequences of basic actions. 433 600-uC-FS-001.book Page 434 Wednesday, October 10, 2012 12:03 PM Appendix C void FSDev_SD_Card_BSP_CmdStart (FS_QTY FS_DEV_SD_CARD_CMD void FS_DEV_SD_CARD_ERR unit_nbr, *p_cmd, *p_data, *p_err) { CPU_INT16U command; CPU_INT32U present_state; CPU_INT16U transfer_mode; present_state = REG_STATE; /* Chk if controller busy. */ (1) if (DEF_BIT_IS_SET_ANY(present_state, BIT_STATE_CMD_INHIBIT_DAT | BIT_STATE_CMD_INHIBIT_CMD) == DEF_YES) { *p_err = FS_DEV_SD_CARD_ERR_BUSY; return; } transfer_mode = DEF_BIT_NONE; /* Calc transfer mode reg value. */ (2) if (p_cmd->DataType == FS_DEV_SD_CARD_DATA_TYPE_MULTIPLE_BLOCK) { transfer_mode |= BIT_TRANSFER_MODE_MULTIPLE_BLOCK | BIT_TRANSFER_MODE_AUTO_CMD12 | BIT_TRANSFER_MODE_BLOCK_COUNT_ENABLE; } if (p_cmd->DataDir == FS_DEV_SD_CARD_DATA_DIR_CARD_TO_HOST) { transfer_mode |= BIT_TRANSFER_MODE_READ | BIT_TRANSFER_MODE_DMA_ENABLE; } else { transfer_mode |= BIT_TRANSFER_MODE_DMA_ENABLE; } command = (CPU_INT16U)p_cmd->Cmd << 8; /* Calc command register value */ (3) if (DEF_BIT_IS_SET(p_cmd->Flags, FS_DEV_SD_CARD_CMD_FLAG_DATA_START) == DEF_YES) { command |= BIT_COMMAND_DATA_PRESENT; } if (DEF_BIT_IS_SET(p_cmd->Flags, FS_DEV_SD_CARD_CMD_FLAG_IX_VALID) == DEF_YES) { command |= BIT_COMMAND_DATA_COMMAND_IX_CHECK; } if (DEF_BIT_IS_SET(p_cmd->Flags, FS_DEV_SD_CARD_CMD_FLAG_CRC_VALID) == DEF_YES) { command |= BIT_COMMAND_DATA_COMMAND_CRC_CHECK; } if (DEF_BIT_IS_SET(p_cmd->Flags, FS_DEV_SD_CARD_CMD_FLAG_RESP) == DEF_YES) { if (DEF_BIT_IS_SET(p_cmd->Flags, FS_DEV_SD_CARD_CMD_FLAG_RESP_LONG) == DEF_YES) { command |= BIT_COMMAND_DATA_COMMAND_RESPONSE_LENGTH_136; } else { if (DEF_BIT_IS_SET(p_cmd->Flags, FS_DEV_SD_CARD_CMD_FLAG_BUSY) == DEF_YES) { command |= BIT_COMMAND_DATA_COMMAND_RESPONSE_LENGTH_48; } else { command |= BIT_COMMAND_DATA_COMMAND_RESPONSE_LENGTH_48_BUSY; } } } 434 600-uC-FS-001.book Page 435 Wednesday, October 10, 2012 12:03 PM /* Write registers to exec cmd. */ (4) REG_SDMA_ADDESS = p_data; REG_BLOCK_COUNT = p_cmd->BlkCnt; REG_BLOCK_SIZE = p_cmd->BlkSize; REG_ARGUMENT = p_cmd->Arg; REG_TRANSFER_MODE = transfer_mode; REG_COMMAND = command; *p_err = FS_DEV_SD_CARD_ERR_NONE; } Listing C-7 FSDev_SD_Card_BSP_CmdStart() LC-7(1) Check whether the controller is busy. Though no successful operation should return without the controller idle, an error condition, programming mistake or unexpected condition could make an assumption about initial controller state false. This simple validation is recommended to avoid side-effects and to aid port debugging. LC-7(2) Calculate the transfer mode register value. The command's DataType and DataDir members specify the type and direction of any transfer. Since this examples uses DMA, DMA is enabled in the transfer mode register. LC-7(3) Calculate the command register value. The command index is available in the command's Cmd member, which is supplemented by the bits OR'd into Flags to describe the expected result--response and data transfer--following the command execution. LC-7(4) The hardware registers are written to execute the command. The sequence in which the registers are written is important. Typically, as in this example, the assignment to the command register actually triggers execution. 435 600-uC-FS-001.book Page 436 Wednesday, October 10, 2012 12:03 PM Appendix C C-5-4 FSDev_SD_Card_BSP_CmdWaitEnd() void FSDev_SD_Card_BSP_CmdWaitEnd (FS_QTY unit_nbr, FS_DEV_SD_CARD_CMD *p_cmd, CPU_INT32U *p_resp, FS_DEV_SD_CARD_ERR *p_err); File Called from Code enabled by fs_dev_sd_card_bsp.c SD/MMC cardmode driver N/A Wait for command to end and get command response. ARGUMENTS unit_nbr Unit number of SD/MMC card. p_cmd Pointer to command that is ending. p_resp Pointer to buffer that will receive command response, if any. p_err Pointer to variable that will receive the return error code from this function: FS_DEV_SD_CARD_ERR_NONE FS_DEV_SD_CARD_ERR_NO_CARD FS_DEV_SD_CARD_ERR_UNKNOWN FS_DEV_SD_CARD_ERR_WAIT_TIMEOUT FS_DEV_SD_CARD_ERR_RESP_TIMEOUT FS_DEV_SD_CARD_ERR_RESP_CHKSUM FS_DEV_SD_CARD_ERR_RESP_CMD_IX FS_DEV_SD_CARD_ERR_RESP_END_BIT FS_DEV_SD_CARD_ERR_RESP FS_DEV_SD_CARD_ERR_DATA 436 No error. No card present. Unknown or other error. Timeout in waiting for command response. Timeout in receiving command response. Error in response checksum. Response command index error. Response end bit error. Other response error. Other data error. 600-uC-FS-001.book Page 437 Wednesday, October 10, 2012 12:03 PM RETURNED VALUE None. NOTES/WARNINGS 1 This function will be called even if no response is expected from the command. 2 This function will not be called if FSDev_SD_Card_BSP_CmdStart() returned an error. 3 The data stored in the response buffer should include only the response data, i.e., should not include the start bit, transmission bit, command index, CRC and end bit. For a command with a normal (48-bit) response, a 4-byte response should be stored in p_resp. For a command with a long (136-bit) response, a 16-byte response should be returned in p_resp: The first 4-byte word should hold bits 127..96 of the response. The second 4-byte word should hold bits 95..64 of the response. The third 4-byte word should hold bits 63..32 of the response. The four 4-byte word should hold bits 31.. 0 of the response. EXAMPLE The implementation of FSDev_SD_Card_BSP_CmdWaitEnd() in is targeted for the same host controller as the other listings in this chapter; for more information, see FSDev_SD_Card_BSP_CmdStart(). 437 600-uC-FS-001.book Page 438 Wednesday, October 10, 2012 12:03 PM Appendix C void FSDev_SD_Card_BSP_CmdWaitEnd (FS_QTY FS_DEV_SD_CARD_CMD CPU_INT32U FS_DEV_SD_CARD_ERR unit_nbr, *p_cmd, *p_resp, *p_err) { CPU_INT16U interrupt_status; CPU_INT16U CPU_INT16U timeout error_status; timeout; = 0u; /* Wait until cmd exec complete.*/ (1) interrupt_status = REG_INTERRUPT_STATUS; while (DEF_BIT_IS_CLR(interrupt_status, BIT_INTERRUPT_STATUS_ERROR | BIT_INTERRUPT_STATUS_COMMAND_COMPLETE) == DEF_YES)) { timeout++; interrupt_status = REG_INTERRUPT_STATUS; if (timeout == TIMEOUT_RESP_MAX) { *p_err = FS_DEV_SD_CARD_ERR_WAIT_TIMEOUT; return; } } /* Handle error. */ (2) if (DEF_BIT_IS_SET(interrupt_status, BIT_INTERRUPT_STATUS_ERROR) == DEF_YES) { error_status = REG_ERROR_STATUS; if (DEF_BIT_IS_SET(error_status, REG_ERROR_STATUS_COMMAND_INDEX) == DEF_YES) { *p_err = FS_DEV_SD_CARD_ERR_RESP_CMD_IX; } else if (DEF_BIT_IS_SET(error_status, REG_ERROR_STATUS_COMMAND_END_BIT) == DEF_YES) { *p_err = FS_DEV_SD_CARD_ERR_RESP_END_BIT; } else if (DEF_BIT_IS_SET(error_status, REG_ERROR_STATUS_COMMAND_CRC) == DEF_YES) { *p_err = FS_DEV_SD_CARD_ERR_RESP_CRC; } else if (DEF_BIT_IS_SET(error_status, REG_ERROR_STATUS_COMMAND_TIMEOUT) == DEF_YES) { *p_err = FS_DEV_SD_CARD_ERR_RESP_TIMEOUT; } else { *p_err = FS_DEV_SD_CARD_ERR_RESP; } REG_ERROR_STATUS = error_status; REG_INTERRUPT_STATUS = interrupt_status; return; } 438 600-uC-FS-001.book Page 439 Wednesday, October 10, 2012 12:03 PM /* Read response. */ (3) REG_INTERRUPT_STATUS = BIT_INTERRUPT_STATUS_COMMAND_COMPLETE; if (DEF_BIT_IS_SET(p_cmd->Flags, FS_DEV_SD_CARD_CMD_FLAG_RESP) == DEF_YES) { if (DEF_BIT_IS_SET(p_cmd->Flags, FS_DEV_SD_CARD_CMD_FLAG_RESP_LONG) == DEF_YES) { *(p_resp + 3) = REG_RESPONSE_00 *(p_resp + 2) = REG_RESPONSE_01 *(p_resp + 1) = REG_RESPONSE_02 *(p_resp + 0) = REG_RESPONSE_03 } else { *(p_resp + 0) = REG_RESPONSE_00 } } *p_err = FS_DEV_SD_CARD_ERR_NONE; } Listing C-8 FSDev_SD_Card_BSP_CmdWaitEnd() LC-8(1) Wait until command execution completes or an error occurs. The wait loop (or wait on semaphore) should always have a timeout to avoid blocking the task in the case of an unforeseen hardware malfunction or a software flaw. LC-8(2) Check if an error occurred. The error status register is decoded to produce the actual error condition. That is not necessary, strictly, but error counters that accumulate within the generic driver based upon returned error values may be useful while debugging a port. LC-8(3) Read the response, if any. Note that the order in which a long response is stored in the buffer may oppose its storage in the controller's register or FIFO. 439 600-uC-FS-001.book Page 440 Wednesday, October 10, 2012 12:03 PM Appendix C C-5-5 FSDev_SD_Card_BSP_CmdDataRd() void FSDev_SD_Card_BSP_CmdDataRd (FS_QTY unit_nbr, FS_DEV_SD_CARD_CMD *p_cmd, void *p_dest, FS_DEV_SD_CARD_ERR *p_err); File Called from Code enabled by fs_dev_sd_card_bsp.c FSDev_SD_Card_RdData() N/A Read data following a command. ARGUMENTS unit_nbr Unit number of SD/MMC card. p_cmd Pointer to command that was started. p_dest Pointer to destination buffer. p_err Pointer to variable that will receive the return error code from this function: FS_DEV_SD_CARD_ERR_NONE FS_DEV_SD_CARD_ERR_NO_CARD FS_DEV_SD_CARD_ERR_UNKNOWN FS_DEV_SD_CARD_ERR_WAIT_TIMEOUT FS_DEV_SD_CARD_ERR_DATA_OVERRUN FS_DEV_SD_CARD_ERR_DATA_TIMEOUT FS_DEV_SD_CARD_ERR_DATA_CHKSUM FS_DEV_SD_CARD_ERR_DATA_START_BIT FS_DEV_SD_CARD_ERR_DATA RETURNED VALUE None. NOTES/WARNINGS None. 440 No error. No card present. Unknown or other error. Timeout in waiting for data. Data overrun. Timeout in receiving data. Error in data checksum. Data start bit error. Other data error. 600-uC-FS-001.book Page 441 Wednesday, October 10, 2012 12:03 PM EXAMPLE The implementation of FSDev_SD_Card_BSP_CmdDataRd() in Listing C-9 is targeted for the same host controller as the other listings in this chapter; for more information, see FSDev_SD_Card_BSP_CmdStart(). void FSDev_SD_Card_BSP_CmdDataRd (FS_QTY FS_DEV_SD_CARD_CMD void FS_DEV_SD_CARD_ERR unit_nbr, *p_cmd, *p_dest, *p_err) { CPU_INT16U interrupt_status; CPU_INT16U error_status; CPU_INT16U timeout; timeout = 0u; /* Wait until data xfer compl. */ (1) interrupt_status = REG_INTERRUPT_STATUS; while (DEF_BIT_IS_CLR(interrupt_status,BIT_INTERRUPT_STATUS_ERROR | BIT_INTERRUPT_STATUS_TRANSFER_COMPLETE) == DEF_YES)) { timeout++; interrupt_status = REG_INTERRUPT_STATUS; if (timeout == TIMEOUT_TRANSFER_MAX) { *p_err = FS_DEV_SD_CARD_ERR_WAIT_TIMEOUT; return; } } /* Handle error. */ (2) if (DEF_BIT_IS_SET(interrupt_status, BIT_INTERRUPT_STATUS_ERROR) == DEF_YES) { error_status = REG_ERROR_STATUS; if (DEF_BIT_IS_SET(error_status, REG_ERROR_STATUS_DATA_END_BIT) == DEF_YES) { *p_err = FS_DEV_SD_CARD_ERR_DATA; } else if (DEF_BIT_IS_SET(error_status, REG_ERROR_STATUS_DATA_CRC) == DEF_YES) { *p_err = FS_DEV_SD_CARD_ERR_DATA_CRC; } else if (DEF_BIT_IS_SET(error_status, REG_ERROR_STATUS_DATA_TIMEOUT) == DEF_YES) { *p_err = FS_DEV_SD_CARD_ERR_DATA_TIMEOUT; } else { *p_err = FS_DEV_SD_CARD_ERR_UNKONWN; } REG_ERROR_STATUS = error_status; REG_INTERRUPT_STATUS = interrupt_status; return; } *p_err = FS_DEV_SD_CARD_ERR_NONE; (3) } Listing C-9 FSDev_SD_Card_BSP_CmdDataRd() 441 600-uC-FS-001.book Page 442 Wednesday, October 10, 2012 12:03 PM Appendix C LC-9(1) Wait until data transfer completes or an error occurs. The wait loop (or wait on semaphore) should always have a timeout to avoid blocking the task in the case of an unforeseen hardware malfunction or a software flaw. LC-9(2) Check if an error occurred. The error status register is decoded to produce the actual error condition. That is not necessary, strictly, but error counters that accumulate within the generic driver based upon returned error values may be useful while debugging a port. LC-9(3) Return no error. The data has been transferred already to the memory buffer using DMA. 442 600-uC-FS-001.book Page 443 Wednesday, October 10, 2012 12:03 PM C-5-6 FSDev_SD_Card_BSP_CmdDataWr() void FSDev_SD_Card_BSP_CmdDataWr (FS_QTY unit_nbr, FS_DEV_SD_CARD_CMD *p_cmd, void *p_src, FS_DEV_SD_CARD_ERR *p_err); File Called from Code enabled by fs_dev_sd_card_bsp.c FSDev_SD_Card_WrData() N/A Write data following a command. ARGUMENTS unit_nbr Unit number of SD/MMC card. p_cmd Pointer to command that was started. p_src Pointer to source buffer. p_err Pointer to variable that will receive the return error code from this function: FS_DEV_SD_CARD_ERR_NONE FS_DEV_SD_CARD_ERR_NO_CARD FS_DEV_SD_CARD_ERR_UNKNOWN FS_DEV_SD_CARD_ERR_WAIT_TIMEOUT FS_DEV_SD_CARD_ERR_DATA_UNDERRUN FS_DEV_SD_CARD_ERR_DATA_CHKSUM FS_DEV_SD_CARD_ERR_DATA_START_BIT FS_DEV_SD_CARD_ERR_DATA No error. No card present. Unknown or other error. Timeout in waiting for data. Data underrun. Error in data checksum. Data start bit error. Other data error. RETURNED VALUE None. NOTES/WARNINGS None. 443 600-uC-FS-001.book Page 444 Wednesday, October 10, 2012 12:03 PM Appendix C EXAMPLE The implementation of FSDev_SD_Card_BSP_CmdDataWr() in Listing C-10 is targeted for the same host controller as the other listings in this chapter; for more information, see FSDev_SD_Card_BSP_CmdStart(). void FSDev_SD_Card_BSP_CmdDataWr (FS_QTY FS_DEV_SD_CARD_CMD void FS_DEV_SD_CARD_ERR unit_nbr, *p_cmd, *p_src, *p_err) { CPU_INT16U interrupt_status; CPU_INT16U error_status; CPU_INT16U timeout; timeout = 0u; /* Wait until data xfer compl. */ (1) interrupt_status = REG_INTERRUPT_STATUS; while (DEF_BIT_IS_CLR(interrupt_status,BIT_INTERRUPT_STATUS_ERROR | BIT_INTERRUPT_STATUS_TRANSFER_COMPLETE) == DEF_YES)) { timeout++; interrupt_status = REG_INTERRUPT_STATUS; if (timeout == TIMEOUT_TRANSFER_MAX) { *p_err = FS_DEV_SD_CARD_ERR_WAIT_TIMEOUT; return; } } /* Handle error. */ (2) if (DEF_BIT_IS_SET(interrupt_status, BIT_INTERRUPT_STATUS_ERROR) == DEF_YES) { error_status = REG_ERROR_STATUS; if (DEF_BIT_IS_SET(error_status, REG_ERROR_STATUS_DATA_END_BIT) == DEF_YES) { *p_err = FS_DEV_SD_CARD_ERR_DATA; } else if (DEF_BIT_IS_SET(error_status, REG_ERROR_STATUS_DATA_CRC) == DEF_YES) { *p_err = FS_DEV_SD_CARD_ERR_DATA_CRC; } else if (DEF_BIT_IS_SET(error_status, REG_ERROR_STATUS_DATA_TIMEOUT) == DEF_YES) { *p_err = FS_DEV_SD_CARD_ERR_DATA_TIMEOUT; } else { *p_err = FS_DEV_SD_CARD_ERR_UNKONWN; } REG_ERROR_STATUS = error_status; REG_INTERRUPT_STATUS = interrupt_status; return; } *p_err = FS_DEV_SD_CARD_ERR_NONE; (3) } Listing C-10 FSDev_SD_Card_BSP_CmdDataWr() 444 600-uC-FS-001.book Page 445 Wednesday, October 10, 2012 12:03 PM LC-10(1) Wait until data transfer completes or an error occurs. The wait loop (or wait on semaphore) SHOULD always have a timeout to avoid blocking the task in the case of an unforeseen hardware malfunction or a software flaw. LC-10(2) Check if an error occurred. The error status register is decoded to produce the actual error condition. That is not necessary, strictly, but error counters that accumulate within the generic driver based upon returned error values may be useful while debugging a port. LC-10(3) Return no error. The data has been transferred already from the memory buffer using DMA. 445 600-uC-FS-001.book Page 446 Wednesday, October 10, 2012 12:03 PM Appendix C C-5-7 FSDev_SD_Card_BSP_GetBlkCntMax() CPU_INT32U FSDev_SD_Card_BSP_GetBlkCntMax (FS_QTY unit_nbr, CPU_INT32U blk_size); File Called from Code enabled by fs_dev_sd_card_bsp.c FSDev_SD_Card_Refresh() N/A Get maximum number of blocks that can be transferred with a multiple read or multiple write command. ARGUMENTS unit_nbr Unit number of SD/MMC card. blk_size Block size, in octets. RETURNED VALUE Maximum number of blocks. NOTES/WARNINGS 1 The DMA region from which data is read or written may be a limited size. The count returned by this function should be the maximum number of blocks of size blk_size that can fit into this region. 2 If the controller is not capable of multiple block reads or writes, 1 should be returned. 3 If the controller has no limit on the number of blocks in a multiple block read or write, DEF_INT_32U_MAX_VAL should be returned. 4 This function SHOULD always return the same value. If hardware constraints change at run-time, the device MUST be closed and re-opened for any changes to be effective. 446 600-uC-FS-001.book Page 447 Wednesday, October 10, 2012 12:03 PM C-5-8 FSDev_SD_Card_BSP_GetBusWidthMax() CPU_INT08U FSDev_SD_Card_BSP_GetBusWidthMax (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_sd_card_bsp.c FSDev_SD_Card_Refresh() N/A Get maximum bus width, in bits. ARGUMENTS unit_nbr Unit number of SD/MMC card. RETURNED VALUE Maximum bus width. NOTES/WARNINGS 1 Legal values are typically 1, 4 and 8. 2 This function should always return the same value. If hardware constraints change at run-time, the device must be closed and re-opened for any changes to be effective. 447 600-uC-FS-001.book Page 448 Wednesday, October 10, 2012 12:03 PM Appendix C C-5-9 FSDev_SD_Card_BSP_SetBusWidth() void FSDev_SD_Card_BSP_SetBusWidth (FS_QTY unit_nbr, CPU_INT08U width); File Called from Code enabled by fs_dev_sd_card_bsp.c FSDev_SD_Card_Refresh(), FSDev_SD_Card_SetBusWidth() N/A Set bus width. ARGUMENTS unit_nbr Unit number of SD/MMC card. width Bus width, in bits. RETURNED VALUE None. NOTES/WARNINGS None. 448 600-uC-FS-001.book Page 449 Wednesday, October 10, 2012 12:03 PM EXAMPLE The implementation of FSDev_SD_Card_BSP_SetBusWidth() in Listing C-11 is targeted for the same host controller as the other listings in this chapter; for more information, see FSDev_SD_Card_BSP_CmdStart(). void FSDev_SD_Card_BSP_SetBusWidth (FS_QTY CPU_INT08U unit_nbr, width) { if (width == 1u) { REG_HOST_CONTROL &= ~BIT_HOST_CONTROL_DATA_TRANSFER_WIDTH; } else { REG_HOST_CONTROL |= BIT_HOST_CONTROL_DATA_TRANSFER_WIDTH; } } Listing C-11 FSDev_SD_Card_BSP_SetBusWidth() 449 600-uC-FS-001.book Page 450 Wednesday, October 10, 2012 12:03 PM Appendix C C-5-10 FSDev_SD_Card_BSP_SetClkFreq() void FSDev_SD_Card_BSP_SetClkFreq (FS_QTY unit_nbr, CPU_INT32U freq); File Called from Code enabled by fs_dev_sd_card_bsp.c FSDev_SD_Card_Refresh() N/A Set clock frequency. ARGUMENTS unit_nbr Unit number of SD/MMC card. freq Clock frequency, in Hz. RETURNED VALUE None. NOTES/WARNINGS The effective clock frequency MUST be no more than freq. If the frequency cannot be configured equal to freq, it should be configured less than freq. 450 600-uC-FS-001.book Page 451 Wednesday, October 10, 2012 12:03 PM C-5-11 FSDev_SD_Card_BSP_SetTimeoutData() void FSDev_SD_Card_BSP_SetTimeoutData (FS_QTY unit_nbr, CPU_INT32U to_clks); File Called from Code enabled by fs_dev_sd_card_bsp.c FSDev_SD_Card_Refresh() N/A Set data timeout. ARGUMENTS unit_nbr Unit number of SD/MMC card. to_clks Timeout, in clocks. RETURNED VALUE None. NOTES/WARNINGS None. 451 600-uC-FS-001.book Page 452 Wednesday, October 10, 2012 12:03 PM Appendix C C-5-12 FSDev_SD_Card_BSP_SetTimeoutResp() void FSDev_SD_Card_BSP_SetTimeoutResp (FS_QTY unit_nbr, CPU_INT32U to_ms); File Called from Code enabled by fs_dev_sd_card_bsp.c FSDev_SD_Card_Refresh() N/A Set data timeout. ARGUMENTS unit_nbr Unit number of SD/MMC card. to_ms Timeout, in milliseconds. RETURNED VALUE None. NOTES/WARNINGS None. C-6 SD/MMC SPI MODE BSP SD/MMC card can also be accessed through an SPI bus (also described as the one-wire mode). Please refer to section C-7 "SPI BSP" on page 453 for the details on how to implement the software port for your SPI bus. 452 600-uC-FS-001.book Page 453 Wednesday, October 10, 2012 12:03 PM C-7 SPI BSP Among the most common--and simplest--serial interfaces supported by built-in CPU peripherals is Serial Peripheral Interface (SPI). Four hardware signals connect a defined master (or host) to each slave (or device): a slave select, a clock, a slave input and a slave output. Three of these, all except the slave select, may be shared among all slaves, though hosts often have several SPI controllers to simplify integration and allow simultaneous access to multiple slaves. Serial flash, serial EEPROM and SD/MMC cards are among the many devices which use SPI. Signal Description SSEL (CS) Slave select SCLK Clock SO (MISO) Slave output (master input) SI (MOSI) Slave input (master output) Table C-3 SPI signals No specification exists for SPI, a condition which invites technological divergence. So though the simplicity of the interface limits variations between implementations, the required transfer unit length, shift direction, clock frequency and clock polarity and phase do vary from device to device. Take as an example Figure C-3 which gives the bit form of a basic command/response exchange on a typical serial flash. The command and response both divide into 8-bit chunks, the transfer unit for the device. Within these units, the data is transferred from most significant bit (MSB) to least significant bit (LSB), which is the slave's shift direction. Though not evident from the diagram--the horizontal axis being labeled in clocks rather than time--the slave cannot operate at a frequency higher than 20-MHz. Finally, the clock signal prior to slave select activation is low (clock polarity or CPOL is 0), and data is latched on the rising clock edge (clock phase or CPHA is 0). Together, those are the aspects of SPI communication that may need to be configured: Transfer unit length. A transfer unit is the underlying unit of commands, responses and data. The most common value is eight bits, though slaves commonly require (and masters commonly support) between 8 and 16 bits. Shift direction. Either the MSB or LSB of each transfer unit can be the first transmitted on the data line. 453 600-uC-FS-001.book Page 454 Wednesday, October 10, 2012 12:03 PM Appendix C Clock frequency. Limits are usually imposed upon the frequency of the clock signal. Of all variable SPI communication parameters, only this one is explicitly set by the device driver. Clock polarity and phase (CPOL and CPHA). SPI communication takes place in any of four modes, depending on the clock phase and clock polarity settings: If CPOL = 0, the clock is low when inactive. If CPOL = 1, the clock is high when inactive. If CPHA = 0, data is "read" on the leading edge of the clock and "changed" on the following edge. If CPHA = 1, data is "changed" on the leading edge of the clock and "read" on the leading edge. The most commonly-supported settings are {CPOL, CPHA} = {0, 0} and {1, 1}. Slave select polarity. The "active" level of the slave select may be electrically high or low. Low is ubiquitous, high rare. Figure C-3 Example SPI transaction 454 600-uC-FS-001.book Page 455 Wednesday, October 10, 2012 12:03 PM A BSP is required that abstracts a CPU's SPI peripheral. The port includes one code file named according to the following rubric: FS_DEV_<dev_name>_BSP.C or FS_DEV_<dev_name>_SPI_BSP.c This file is generally placed with other BSP files in a directory named according to the following rubric: \Micrium\Software\EvalBoards\<manufacturer>\<board_name> \<compiler>\BSP\ Several example ports are included in the C/FS distribution in files named according to the following rubric: \Micrium\Software\uC-FS\Examples\BSP\Dev\NAND\<manufacturer>\<cpu_name> \Micrium\Software\uC-FS\Examples\BSP\Dev\NOR\<manufacturer>\<cpu_name> \Micrium\Software\uC-FS\Examples\BSP\Dev\SD\SPI\<manufacturer>\<cpu_name> Check all of these directories for ports for a CPU if porting any SPI device; the CPU may be been used with a different type of device, but the port should support another with none or few modifications. Each port must implement the functions to be placed into a FS_DEV_SPI_API structure: const FS_DEV_SPI_API FSDev_####_BSP_SPI = { FSDev_BSP_SPI_Open, FSDev_BSP_SPI_Close, FSDev_BSP_SPI_Lock, FSDev_BSP_SPI_Unlock, FSDev_BSP_SPI_Rd, FSDev_BSP_SPI_Wr, FSDev_BSP_SPI_ChipSelEn, FSDev_BSP_SPI_ChipSelDis, FSDev_BSP_SPI_SetClkFreq }; The functions which must be implemented are listed and described in Table C-4. SPI is no more than a physical interconnect. The protocol of command-response interchange the master follows to control a slave is specified on a per-slave basis. Control of the chip select (SSEL) is separated from the reading and writing of data to the slave because multiple bus 455 600-uC-FS-001.book Page 456 Wednesday, October 10, 2012 12:03 PM Appendix C transactions (e.g., a read then a write then another read) are often performed without breaking slave selection. Indeed, some slaves require bus transactions (or "empty" clocks) AFTER the select has been disabled. Function Description Open() Open (initialize) hardware for SPI. Close() Close (uninitialize) hardware for SPI. Lock() Acquire SPI bus lock. Unlock() Release SPI bus lock. Rd() Read from SPI bus. Wr() Write to SPI bus. ChipSelEn() Enable device chip select. ChipSelDis() Disable device chip select SetClkFreq() Set SPI clock frequency Table C-4 SPI port functions The first argument of each of these port functions is the device unit number, an identifier unique to each driver/device type--after all, it is the number in the device name. For example, "sd:0:" and "nor:0:" both have unit number 1. If two SPI devices are located on the same SPI bus, either of two approaches can resolve unit number conflicts: Unique unit numbers. All devices on the same bus can use the same SPI BSP if and only if each device has a unique unit number. For example, the SD/MMC card "sd:0:" and serial NOR "nor:1:" require only one BSP. Unique SPI BSPs. Devices of different types (e.g., a SD/MMC card and a serial NOR) can have the same unit number if and only if each device uses a separate BSP. For example, the SD/MMC card "sd:0:" and serial "nor:0:" require separate BSPs. 456 600-uC-FS-001.book Page 457 Wednesday, October 10, 2012 12:03 PM C-7-1 Open() CPU_BOOLEAN FSDev_BSP_SPI_Open (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_<dev_name>_bsp.c Device driver N/A Open (initialize) hardware for SPI. ARGUMENTS unit_nbr Unit number of device. RETURNED VALUE DEF_OK, if interface was opened. DEF_FAIL, otherwise. NOTES/WARNINGS 1 This function will be called every time the device is opened. 2 Several aspects of SPI communication may need to be configured, including: a. Transfer unit length b. Shift direction c. Clock frequency d. Clock polarity and phase (CPOL and CPHA) e. Slave select polarity 457 600-uC-FS-001.book Page 458 Wednesday, October 10, 2012 12:03 PM Appendix C 3 For a SD/MMC card, the following settings should be used: a. Transfer unit length: 8-bits b. Shift direction: MSB first c. Clock frequency: 400-kHz (initially) d. Clock polarity and phase (CPOL and CPHA): CPOL = 0, CPHA = 0 e. Slave select polarity: active low. 4 458 The slave select (SSEL or CS) MUST be configured as a GPIO output; it should not be controlled by the CPU's SPI peripheral. The SPI port's ChipSelEn() and ChipSelDis() functions manually enable and disable the SSEL. 600-uC-FS-001.book Page 459 Wednesday, October 10, 2012 12:03 PM C-7-2 Close() void FSDev_BSP_SPI_Close (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_<dev_name>_bsp.c Device driver N/A Close (uninitialize) hardware for SPI. ARGUMENTS unit_nbr Unit number of device. RETURNED VALUE None. NOTES/WARNINGS This function will be called every time the device is closed. 459 600-uC-FS-001.book Page 460 Wednesday, October 10, 2012 12:03 PM Appendix C C-7-3 Lock() / Unlock() void FSDev_BSP_SPI_Lock (FS_QTY unit_nbr); void FSDev_BSP_SPI_Unlock (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_<dev_name>_bsp.c Device driver N/A Acquire/release SPI bus lock. ARGUMENTS unit_nbr Unit number of device. RETURNED VALUE None. NOTES/WARNINGS Lock() will be called before the driver begins to access the SPI. The application should NOT use the same bus to access another device until the matching call to Unlock() has been made. The clock frequency set by the SetClkFreq() function is a parameter of the device, not the bus. If multiple devices are located on the same bus, those parameters must be saved (in memory) when set and restored by Lock(). The same should be done for initialization parameters such as transfer unit size and shift direction that vary from device to device. 460 600-uC-FS-001.book Page 461 Wednesday, October 10, 2012 12:03 PM C-7-4 Rd() void FSDev_BSP_SPI_Rd (FS_QTY unit_nbr, void *p_dest, CPU_SIZE_T cnt); File Called from Code enabled by fs_dev_<dev_name>_bsp.c Device driver N/A Read from SPI bus. ARGUMENTS unit_nbr Unit number of device. p_dest Pointer to destination buffer. cnt Number of octets to read. RETURNED VALUE None. NOTES/WARNINGS None. 461 600-uC-FS-001.book Page 462 Wednesday, October 10, 2012 12:03 PM Appendix C C-7-5 Wr() void FSDev_BSP_SPI_Wr (FS_QTY unit_nbr, void *p_src, CPU_SIZE_T cnt); File Called from Code enabled by fs_dev_<dev_name>_bsp.c Device driver N/A Write to SPI bus. ARGUMENTS unit_nbr Unit number of device. p_src Pointer to source buffer. cnt Number of octets to write. RETURNED VALUE None. NOTES/WARNINGS None. 462 600-uC-FS-001.book Page 463 Wednesday, October 10, 2012 12:03 PM C-7-6 ChipSelEn() /ChipSelDis() void FSDev_BSP_SPI_ChipSelEn (FS_QTY unit_nbr); void FSDev_BSP_SPI_ChipSelDis (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_<dev_name>_bsp.c Device driver N/A Enable/disable device chip select. ARGUMENTS unit_nbr Unit number of device. RETURNED VALUE None. NOTES/WARNINGS The chip select is typically "active low". To enable the device, the chip select pin should be cleared; to disable the device, the chip select pin should be set. 463 600-uC-FS-001.book Page 464 Wednesday, October 10, 2012 12:03 PM Appendix C C-7-7 SetClkFreq() void FSDev_BSP_SPI_SetClkFreq (FS_QTY unit_nbr, CPU_INT32U freq); File Called from Code enabled by fs_dev_<dev_name>_bsp.c Device driver N/A Set SPI clock frequency. ARGUMENTS unit_nbr Unit number of device. RETURNED VALUE None. NOTES/WARNINGS The effective clock frequency must be no more than freq. If the frequency cannot be configured equal to freq, it should be configured less than freq. C-8 NAND FLASH PHYSICAL-LAYER DRIVER The information about porting the NAND driver to a new platform, through either a controller layer implementation or a generic controller BSP is available in Chapter 13, "NAND Flash Driver" on page 159. C-9 NOR FLASH PHYSICAL-LAYER DRIVER The NOR driver is divided into three layers. The topmost layer, the generic driver, requires an intermediate physical-layer driver to effect flash operations like erasing blocks and writing octets. The physical-layer driver includes one code/header file pair named according to the following rubric: FS_DEV_NOR_<device_name>.C 464 600-uC-FS-001.book Page 465 Wednesday, October 10, 2012 12:03 PM FS_DEV_NOR_<device_name>.H A non-uniform flash--a flash with some blocks of one size and some blocks of another-- will require a custom driver adapted from the generic driver for the most similar medium type. Multiple small blocks should be grouped together to form large blocks, effectively making the flash appear uniform to the generic driver. A custom physical-layer driver can also implement advanced program operations unique to a NOR device family. The physical-layer driver acts via a BSP. The generic drivers for traditional NOR flash require a BSP as described in Appendix C, "NOR Flash BSP" on page 473. The drivers for SPI flash require a SPI BSP as described in Appendix C, "NOR Flash SPI BSP" on page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igure C-4 NOR driver architecture Each physical-layer driver must implement the functions to be placed into a FS_DEV_NOR_PHY_API structure: 465 600-uC-FS-001.book Page 466 Wednesday, October 10, 2012 12:03 PM Appendix C const FS_DEV_NOR_PHY_API FSDev_NOR_PHY_Open, FSDev_NOR_PHY_Close, FSDev_NOR_#### { FSDev_NOR_PHY_Rd, FSDev_NOR_PHY_Wr, FSDev_NOR_PHY_EraseBlk, FSDev_NOR_PHY_IO_Ctrl, }; The functions which must be implemented are listed and described in Table C-5. The first argument of each of these is a pointer to a FS_DEV_NOR_PHY_DATA structure which holds physical device information. Specific members will be described in subsequent sections as necessary. The NOR driver populates an internal instance of this type based upon configuration information. Before the file system suite has been initialized, the application may do the same if raw device accesses are a necessary part of its start-up procedure. Function Description Open() Open (initialize) a NOR device and get NOR device information. Close() Close (uninitialize) a NOR device. Rd() Read from a NOR device and store data in buffer. Wr() Write to a NOR device from a buffer. EraseBlk() Erase block of NOR device. IO_Ctrl() Perform NOR device I/O control operation. Table C-5 NOR flash physical-layer driver functions 466 600-uC-FS-001.book Page 467 Wednesday, October 10, 2012 12:03 PM C-9-1 Open() void Open (FS_DEV_NOR_PHY_DATA *p_phy_data, FS_ERR *p_err); File Called from Code enabled by NOR physical-layer driver FSDev_NOR_Open() N/A Open (initialize) a NOR device instance and get NOR device information. ARGUMENTS p_phy_data Pointer to NOR phy data. p_err Pointer to variable that will receive the return error code from this function. RETURNED VALUE None. NOTES/WARNINGS Several members of p_phy_data may need to be used/assigned: 1 BlkCnt and BlkSize must be assigned the block count and block size of the device, respectively. 2 RegionNbr specifies the block region that will be used. AddrRegionStart must be assigned the start address of this block region. 3 DataPtr may store a pointer to any driver-specific data. 4 UnitNbr is the unit number of the NOR device. 5 MaxClkFreq specifies the maximum SPI clock frequency. 6 BusWIdth, BusWidthMax and PhyDevCnt specify the bus configuration. AddrBase specifies the base address of the NOR flash memory. 467 600-uC-FS-001.book Page 468 Wednesday, October 10, 2012 12:03 PM Appendix C C-9-2 Close() void Close (FS_DEV_NOR_PHY_DATA *p_phy_data); File Called from Code enabled by NOR physical-layer driver FSDev_NOR_Close() N/A Close (uninitialize) a NOR device instance. ARGUMENTS p_phy_data Pointer to NOR phy data. RETURNED VALUE None. NOTES/WARNINGS None. 468 600-uC-FS-001.book Page 469 Wednesday, October 10, 2012 12:03 PM C-9-3 Rd() void Rd (FS_DEV_NOR_PHY_DATA *p_phy_data, void *p_dest, CPU_INT32U start, CPU_INT32U cnt, FS_ERR *p_err); File Called from Code enabled by NOR physical-layer driver FSDev_NOR_PhyRdHandler() N/A Read from a NOR device and store data in buffer. ARGUMENTS p_phy_data Pointer to NOR phy data. p_dest Pointer to destination buffer. start Start address of read (relative to start of device). cnt Number of octets to read. p_err Pointer to variable that will receive the return error code from this function. FS_ERR_NONE FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Octets read successfully. Device I/O error. Device timeout error. RETURNED VALUE None. NOTES/WARNINGS None. 469 600-uC-FS-001.book Page 470 Wednesday, October 10, 2012 12:03 PM Appendix C C-9-4 Wr() void Wr (FS_DEV_NOR_PHY_DATA *p_phy_data, void *p_src, CPU_INT32U start, CPU_INT32U cnt, FS_ERR *p_err); File Called from Code enabled by NOR physical-layer driver FSDev_NOR_PhyWrHandler() N/A Write to a NOR device from a buffer. ARGUMENTS p_phy_data Pointer to NOR phy data. p_src Pointer to source buffer. start Start address of write (relative to start of device). cnt Number of octets to write. p_err Pointer to variable that will receive the return error code from this function. FS_ERR_NONE FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT RETURNED VALUE None. NOTES/WARNINGS None. 470 Octets written successfully. Device I/O error. Device timeout error. 600-uC-FS-001.book Page 471 Wednesday, October 10, 2012 12:03 PM C-9-5 EraseBlk() void EraseBlk (FS_DEV_NOR_PHY_DATA *p_phy_data, CPU_INT32U start, CPU_INT32U size, FS_ERR *p_err); File Called from Code enabled by NOR physical-layer driver FSDev_NOR_PhyEraseBlkHandler() N/A Erase block of NOR device. ARGUMENTS p_phy_data Pointer to NOR phy data. start Start address of block (relative to start of device). size Size of block, in octets p_err Pointer to variable that will receive the return error code from this function. FS_ERR_NONE FS_ERR_DEV_INVALID_OP FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Block erased successfully. Invalid operation for device. Device I/O error. Device timeout error. RETURNED VALUE None. NOTES/WARNINGS None. 471 600-uC-FS-001.book Page 472 Wednesday, October 10, 2012 12:03 PM Appendix C C-9-6 IO_Ctrl() void IO_Ctrl (FS_DEV_NOR_PHY_DATA *p_phy_data, CPU_INT08U opt, void *p_data, FS_ERR *p_err); File Called from Code enabled by NOR physical-layer driver various N/A Perform NOR device I/O control operation. ARGUMENTS p_phy_data Pointer to NOR phy data. opt Control command. p_data Buffer which holds data to be used for operation. OR Buffer in which data will be stored as a result of operation. p_err Pointer to variable that will receive the return error code from this function. FS_ERR_NONE FS_ERR_DEV_INVALID_IO_CTRL I/O FS_ERR_DEV_INVALID_OP FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT RETURNED VALUE None. NOTES/WARNINGS None. 472 Control operation performed successfully. Control unknown to driver. Invalid operation for device. Device I/O error. Device timeout error. 600-uC-FS-001.book Page 473 Wednesday, October 10, 2012 12:03 PM C-10 NOR FLASH BSP A "traditional" NOR flash has two buses, one for addresses and another for data. For example, the host initiates a data read operation with the address of the target location latched onto the address bus; the device responds by outputting a data word on the data bus. A BSP abstracts the flash interface for the physical layer driver. The port includes one code file: FS_DEV_NOR_BSP.C This file is generally placed with other BSP files in a directory named according to the following rubric: \Micrium\Software\EvalBoards\<manufacturer>\<board_name> \<compiler>\BSP\ Function Description FSDev_NOR_BSP_Open() Open (initialize) bus for NOR FSDev_NOR_BSP_Close() Close (uninitialize) bus for NOR. FSDev_NOR_BSP_Rd_08()/16() Read from bus interface. FSDev_NOR_BSP_RdWord_08()/16() Read word from bus interface. FSDev_NOR_BSP_WrWord_08()/16() Write word to bus interface. FSDev_NOR_BSP_WaitWhileBusy() Wait while NOR is busy. Table C-6 NOR BSP functions 473 600-uC-FS-001.book Page 474 Wednesday, October 10, 2012 12:03 PM Appendix C C-10-1 FSDev_NOR_BSP_Open() CPU_BOOLEAN FSDev_NOR_BSP_Open (FS_QTY CPU_ADDR CPU_INT08U CPU_INT08U unit_nbr, addr_base, bus_width, phy_dev_cnt); File Called from Code enabled by fs_dev_nor_bsp.c NOR physical-layer driver N/A Open (initialize) bus for NOR. ARGUMENTS unit_nbr Unit number of NOR. addr_base Base address of NOR. bus_width Bus width, in bits. phy_dev_cnt Number of devices interleaved. RETURNED VALUE DEF_OK, if interface was opened. DEF_FAIL, otherwise. NOTES/WARNINGS This function will be called every time the device is opened. 474 600-uC-FS-001.book Page 475 Wednesday, October 10, 2012 12:03 PM C-10-2 FSDev_NOR_BSP_Close() void FSDev_NOR_BSP_Close (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_nor_bsp.c NOR physical-layer driver N/A Close (uninitialize) bus for NOR. ARGUMENTS unit_nbr Unit number of NOR. RETURNED VALUE None. NOTES/WARNINGS This function will be called every time the device is closed. 475 600-uC-FS-001.book Page 476 Wednesday, October 10, 2012 12:03 PM Appendix C C-10-3 FSDev_NOR_BSP_Rd_XX() void FSDev_NAND_BSP_Rd_08 (FS_QTY unit_nbr, void *p_dest, CPU_ADDR addr_src, CPU_SIZE_T cnt); void FSDev_NAND_BSP_Rd_16 (FS_QTY unit_nbr, void *p_dest, CPU_ADDR addr_src, CPU_SIZE_T cnt); File Called from Code enabled by fs_dev_nor_bsp.c NOR physical-layer driver N/A Read data from bus interface. ARGUMENTS unit_nbr Unit number of NOR. p_dest Pointer to destination memory buffer. addr_src Source address. cnt Number of words to read. RETURNED VALUE None. NOTES/WARNINGS Data should be read from the bus in words sized to the data bus; for any unit, only the function with its access width will be called. 476 600-uC-FS-001.book Page 477 Wednesday, October 10, 2012 12:03 PM C-10-4 FSDev_NOR_BSP_RdWord_XX() CPU_INT08U FSDev_NAND_BSP_RdWord_08 (FS_QTY CPU_ADDR CPU_INT16U FSDev_NAND_BSP_RdWord_16 (FS_QTY CPU_ADDR unit_nbr, addr_src); unit_nbr, addr_src); File Called from Code enabled by fs_dev_nor_bsp.c NOR physical-layer driver N/A Read data from bus interface. ARGUMENTS unit_nbr Unit number of NOR. addr_src Source address. RETURNED VALUE Word read. NOTES/WARNINGS Data should be read from the bus in words sized to the data bus; for any unit, only the function with its access width will be called. 477 600-uC-FS-001.book Page 478 Wednesday, October 10, 2012 12:03 PM Appendix C C-10-5 FSDev_NOR_BSP_WrWord_XX() void FSDev_NAND_BSP_WrWord_08 (FS_QTY CPU_ADDR CPU_INT08U void FSDev_NAND_BSP_WrWord_16 (FS_QTY CPU_ADDR CPU_INT16U unit_nbr, addr_src, datum); unit_nbr, addr_src, datum); File Called from Code enabled by fs_dev_nor_bsp.c NOR physical-layer driver N/A Write data to bus interface. ARGUMENTS unit_nbr Unit number of NOR. addr_src Source address. datum Word to write. RETURNED VALUE None. NOTES/WARNINGS Data should be written o the bus in words sized to the data bus; for any unit, only the function with its access width will be called. 478 600-uC-FS-001.book Page 479 Wednesday, October 10, 2012 12:03 PM C-10-6 FSDev_NOR_BSP_WaitWhileBusy() CPU_BOOLEAN FSDev_NOR_BSP_WaitWhileBusy (FS_QTY unit_nbr, FS_DEV_NOR_PHY_DATA *p_phy_data, CPU_BOOLEAN (*poll_fnct)(FS_DEV_NOR_PHY_DATA *), CPU_INT32U to_us); File Called from Code enabled by fs_dev_nor_bsp.c NOR physical-layer driver N/A Wait while NAND is busy. ARGUMENTS unit_nbr Unit number of NOR. p_phy_data Pointer to NOR phy data. poll_fnct Pointer to function to poll, if there is no hardware ready/busy signal. to_us Timeout, in microseconds. RETURNED VALUE DEF_OK, if NAND became ready. DEF_FAIL, otherwise. NOTES/WARNINGS None. 479 600-uC-FS-001.book Page 480 Wednesday, October 10, 2012 12:03 PM Appendix C CPU_BOOLEAN FSDev_NOR_BSP_WaitWhileBusy (FS_QTY FS_DEV_NOR_PHY_DATA CPU_BOOLEAN CPU_INT32U unit_nbr, *p_phy_data, (*poll_fnct)(FS_DEV_NOR_PHY_DATA to_us) *), { CPU_INT32U CPU_INT32U CPU_BOOLEAN time_cur_us; time_start_us; rdy; time_cur_us = /* $$$$ GET CURRENT TIME, IN MICROSECONDS. */; time_start_us = time_cur_us; while (time_cur_us - time_start_us < to_us) { rdy = poll_fnct(p_phy_data); if (rdy == DEF_OK) { return (DEF_OK); (1) (2) } time_cur_us = /* $$$$ GET CURRENT TIME, IN MICROSECONDS. */; } return (DEF_FAIL); (3) } Listing C-12 FSDev_NOR_BSP_WaitWhileBusy() (without hardware read/busy signal) LC-12(1) At least to_us microseconds should elapse before the function gives up and returns. Returning early can cause disruptive timeout errors within the physical-layer driver. LC-12(2) poll_fnct should be called with p_phy_data as its sole argument. If it returns DEF_OK, then the device is ready and the function should return DEF_OK. LC-12(3) If to_us microseconds elapse without the poll function or hardware ready/busy signaling indicating success, the function should return DEF_FAIL. C-11 NOR FLASH SPI BSP The NOR driver must adapt to the specific hardware using a BSP. A serial NOR Flash will be interfaced on a SPI bus. See Appendix C, "SPI BSP" on page 453 for the details on how to implement the software port for your SPI bus. 480 600-uC-FS-001.book Page 481 Wednesday, October 10, 2012 12:03 PM Appendix D C/FS Types and Structures Your application may need to access or populate the types and structures described in this appendix. Each of the user-accessible structures is presented in alphabetical order. The following information is provided for each entry: A brief description of the type or structure. The definition of the type or structure. The filename of the source code. A description of the meaning of the type or the members of the structure. Specific notes and warnings regarding use of the type. 481 600-uC-FS-001.book Page 482 Wednesday, October 10, 2012 12:03 PM Appendix D D-1 FS_CFG typedef struct fs_cfg { FS_QTY DevCnt; FS_QTY VolCnt; FS_QTY FileCnt; FS_QTY DirCnt; FS_QTY BufCnt; FS_QTY DevDrvCnt; FS_SEC_SIZE MaxSecSize; } FS_CFG; File Used for fs.h First argument of FS_Init() A pointer to a FS_CFG structure is the argument of FS_Init(). It configures the number of devices, files and other objects in the file system suite. MEMBERS DevCnt The maximum number of devices that can be open simultaneously. MUST be greater than or equal to 1. VolCnt The maximum number of volumes that can be open simultaneously. MUST be greater than or equal to 1. FileCnt The maximum number of files that can be open simultaneously. MUST be greater than or equal to 1. DirCnt Maximum number of directories that can be open simultaneously. If DirCnt is 0, the directory module functions will be blocked after successful initialization, and the file system will operate as if compiled with directory support disabled. If directory support is disabled, DirCnt is ignored; otherwise, if directories will be used, DirCnt should be greater than or equal to 1. 482 600-uC-FS-001.book Page 483 Wednesday, October 10, 2012 12:03 PM BufCnt Maximum number of buffers that can be used successfully. The minimum necessary BufCnt can be calculated from the number of volumes: BufCnt >= VolCnt * 2 If FSEntry_Copy() or FSEntry_Rename() is used, then up to one additional buffer for each volume may be necessary. DevDrvCnt Maximum number of device drivers that can be added. It MUST be greater than or equal to 1. MaxSecSize Maximum sector size, in octets. It must be 512, 1024, 2048 or 4096. No device with a sector size larger than MaxSecSize can be opened. NOTES None. 483 600-uC-FS-001.book Page 484 Wednesday, October 10, 2012 12:03 PM Appendix D D-2 FS_DEV_INFO typedef struct fs_dev_info { FS_STATE State; FS_SEC_QTY Size; FS_SEC_SIZE SecSize; CPU_BOOLEAN Fixed; } FS_DEV_INFO; File Used for fs_dev.h Second argument of FSDev_Query() Receives information about a device. MEMBERS State The device state: FS_DEV_STATE_CLOSED FS_DEV_STATE_CLOSING FS_DEV_STATE_OPENING FS_DEV_STATE_OPEN FS_DEV_STATE_PRESENT FS_DEV_STATE_LOW_FMT_VALID Device is closed. Device is closing. Device is opening. Device is open, but not present. Device is present, but not low-level formatted. Device low-level format is valid. Size The number of sectors on the device. SecSize The size of each device sector. Fixed Indicates whether the device is fixed or removable. NOTES None. 484 600-uC-FS-001.book Page 485 Wednesday, October 10, 2012 12:03 PM D-3 FS_DEV_NOR_CFG typedef struct fs_dev_nor_cfg { CPU_ADDR AddrBase; CPU_INT08U RegionNbr; CPU_ADDR AddrStart; CPU_INT32U DevSize; FS_SEC_SIZE SecSize; CPU_INT08U PctRsvd; CPU_INT16U EraseCntDiffTh; FS_DEV_NOR_PHY_API *PhyPtr; CPU_INT08U BusWidth; CPU_INT08U BusWidthMax; CPU_INT08U PhyDevCnt; CPU_INT32U MaxClkFreq; } FS_DEV_NOR_CFG; File Used for fs_dev_nor.h Second argument of FSDev_Open() (when opening a NOR device) Configures the properties of a NOR device that will be opened. A pointer to this structure is passed as the second argument of FSDev_Open() for a NOR device. MEMBERS AddrBase must specify 1. the base address of the NOR flash memory, for a parallel NOR. 2. 0x00000000 for a serial NOR. RegionNbr must specify the block region which will be used for the file system area. Block regions are enumerated by the physical-layer driver; for more information, see the physical-layer driver header file. (on monolithic devices, devices with only one block region, this must be 0). 485 600-uC-FS-001.book Page 486 Wednesday, October 10, 2012 12:03 PM Appendix D AddrStart must specify 1. the absolute start address of the file system area in the NOR flash memory, for a paralel NOR. 2. the offset of the start of the file system in the NOR flash, for a serial NOR. The address specified by AddrStart MUST lie within the region RegionNbr. DevSize must specify the number of octets that will belong to the file system area. SecSize must specify the sector size for the NOR flash (either 512, 1024, 2048 or 4096). PctRsvd must specify the percentage of sectors on the NOR flash that will be reserved for extra-file system storage (to improve efficiency). This value must be between 5% and 35%, except if 0 is specified whereupon the default will be used (10%). EraseCntDiffTh PhyPtr must specify the difference between minimum and maximum erase counts that will trigger passive wear-leveling. This value must be between 5 and 100, except if 0 is specified whereupon the default will be used (20). must point to the appropriate physical-layer driver: FSDev_NOR_AMD_1x08 FSDev_NOR_AMD_1x16 FSDev_NOR_Intel_1x16 FSDev_NOR_SST39 486 CFI-compatible parallel NOR implementing AMD command set, 8-bit data bus. CFI-compatible parallel NOR implementing AMD command set, 16-bit data bus. CFI-compatible parallel NOR implementing Intel command set, 16-bit data bus SST SST39 Multi-Purpose Flash 600-uC-FS-001.book Page 487 Wednesday, October 10, 2012 12:03 PM FSDev_NOR_STM25 FSDev_NOR_SST25 Other ST M25 serial flash SST SST25 serial flash User-developed For a parallel NOR, the bus configuration is specified via BusWidth, BusWidthMax and PhyDevCnt: BusWidth is the bus width, in bits, between the MCU/MPU and each connected device. BusWidthMax is the maximum width supported by each connected device. PhyDevCnt is the number of devices interleaved on the bus. For a serial flash, the maximum clock frequency is specified via MaxClkFreq. NOTES None. 487 600-uC-FS-001.book Page 488 Wednesday, October 10, 2012 12:03 PM Appendix D D-4 FS_DEV_RAM_CFG typedef struct fs_dev_ram_cfg { FS_SEC_SIZE SecSize; FS_SEC_QTY Size; void *DiskPtr; } FS_DEV_RAM_CFG; File Used for fs_dev_ramdisk.h Second argument of FSDev_Open() (when opening a RAM disk) Configures the properties of a RAM disk that will be opened. A pointer to this structure is passed as the second argument of FSDev_Open() for a RAM disk. MEMBERS SecSize The sector size of RAM disk, either 512, 1024, 2048 or 4096. Size The size of the RAM disk, in sectors. DiskPtr The pointer to the RAM disk. NOTES None. 488 600-uC-FS-001.book Page 489 Wednesday, October 10, 2012 12:03 PM D-5 FS_DIR_ENTRY (struct fs_dirent) typedef struct fs_dirent { CPU_CHAR Name[FS_CFG_MAX_FILE_NAME_LEN + 1u]; FS_ENTRY_INFO Info; } FS_DIR_ENTRY; File Used for fs_dir.h Second argument of fs_readdir_r() and FSDir_Rd() Receives information about a directory entry. MEMBERS Name The name of the file. Info Entry information. For more information, see section D-2 "FS_DEV_INFO" on page 484 NOTES None. 489 600-uC-FS-001.book Page 490 Wednesday, October 10, 2012 12:03 PM Appendix D D-6 FS_ENTRY_INFO typedef struct fs_entry_info { FS_FLAGS Attrib; FS_FILE_SIZE Size; CLK_TS_SEC DateTimeCreate; CLK_TS_SEC DateAccess; CLK_TS_SEC DateTimeWr; FS_SEC_QTY BlkCnt; FS_SEC_SIZE BlkSize; } FS_ENTRY_INFO; File Used for fs_entry.h Second argument of FSEntry_Query() and FSFileQuery(); The Info member of FS_DIR_ENTRY (struct fs_dirent) Receives information about a file or directory. MEMBERS Attrib The file or directory attributes (see section 6-2-1 "File and Directory Attributes" on page 90). Size The size of the file, in octets. DateTimeCreate The creation timestamp of the file or directory. DateAccess The last access date of the file or directory. DateTimeWr The last write (or modification) timestamp of the file or directory. 490 600-uC-FS-001.book Page 491 Wednesday, October 10, 2012 12:03 PM BlkCnt The number of blocks allocated to the file. For a FAT file system, this is the number of clusters occupied by the file data. BlkSize The size of each block allocated in octets. For a FAT file system, this is the size of a cluster. NOTES None. 491 600-uC-FS-001.book Page 492 Wednesday, October 10, 2012 12:03 PM Appendix D D-7 FS_FAT_SYS_CFG typedef struct fs_fat_sys_cfg { FS_SEC_QTY ClusSize; FS_FAT_SEC_NBR RsvdAreaSize; CPU_INT16U RootDirEntryCnt; CPU_INT08U FAT_Type; CPU_INT08U NbrFATs; } FS_FAT_SYS_CFG; File Used for fs_fat_type.h Second argument of FSVol_Fmt() when opening a FAT volume (optional) A pointer to a FS_FAT_SYS_CFG structure may be passed as the second argument of FSVol_Fmt(). It configures the properties of the FAT file system that will be created. MEMBERS ClusSize The size of a cluster, in sectors. This should be 1, 2, 4, 8, 16, 32, 64 or 128. The size of a cluster, in bytes, must be less than or equal to 65536, so some of the upper values may be invalid for devices with large sector sizes. RsvdAreaSize The size of the reserved area on the disk, in sectors. For FAT12 and FAT16 volumes, the reserved should be 1 sector; for FAT32 volumes, 32 sectors. RootDirEntryCnt The number of entries in the root directory. This applies only to FAT12 and FAT16 volumes, on which the root directory is a separate area of the file system and is a fixed size. The root directory entry count caps the number of files and directories that can be located in the root directory. FAT_Type 492 The type of FAT. This should be 12 (for FAT12), 16 for (FAT16) or 32 (for FAT32). Ths choice of FAT type must observe restrictions on the maximum number a clusters. A FAT12 file system may have no more than 4085 clusters; a FAT16 file system, no more than 65525. 600-uC-FS-001.book Page 493 Wednesday, October 10, 2012 12:03 PM NbrFATs The number of actual FATs (file allocation tables) to create on the disk. The typical value is 2 (one for primary use, a secondary for backup). NOTES Further restrictions on the members of this structure can be found in Chapter 4, "File Systems: FAT" on page 153. 493 600-uC-FS-001.book Page 494 Wednesday, October 10, 2012 12:03 PM Appendix D D-8 FS_PARTITION_ENTRY typedef struct fs_partition_entry { FS_SEC_NBR Start; FS_SEC_QTY Size; CPU_INT08U Type; } FS_PARTITION_ENTRY; File Used for fs_partition.h Third argument of FSDev_PartitionFind() Receives information about a partition entry. MEMBERS Start The start sector of partition. Size The size of partition, in sectors. Type The type of data in the partition. NOTES None. 494 600-uC-FS-001.book Page 495 Wednesday, October 10, 2012 12:03 PM D-9 FS_VOL_INFO typedef struct fs_vol_info { FS_STATE State; FS_STATE DevState; FS_SEC_QTY DevSize; FS_SEC_SIZE DevSecSize; FS_SEC_QTY PartitionSize; FS_SEC_QTY VolBadSecCnt; FS_SEC_QTY VolFreeSecCnt; FS_SEC_QTY VolUsedSecCnt; FS_SEC_QTY VolTotSecCnt; } FS_VOL_INFO; File Used for fs_vol.h Second argument of FSVol_Query() Receives information about a volume. MEMBERS State The volume state: FS_VOL_STATE_CLOSED FS_VOL_STATE_CLOSING FS_VOL_STATE_OPENING FS_VOL_STATE_OPEN FS_VOL_STATE_PRESENT FS_VOL_STATE_MOUNTED DevState Volume Volume Volume Volume Volume Volume is closed. is closing. is opening. is open. device is present. is mounted. The device state: FS_DEV_STATE_CLOSED FS_DEV_STATE_CLOSING FS_DEV_STATE_OPENING FS_DEV_STATE_OPEN FS_DEV_STATE_PRESENT FS_DEV_STATE_LOW_FMT_VALID Device is closed. Device is closing. Device is opening. Device is open, but not present. Device is present, but not low-level formatted. Device low-level format is valid. 495 600-uC-FS-001.book Page 496 Wednesday, October 10, 2012 12:03 PM Appendix D DevSize The number of sectors on the device. DevSecSize The size of each device sector. PartitionSize The number of sectors in the partition. VolBadSecCnt The number of bad sectors on the volume. VolFreeSecCnt The number of free sectors on the volume. VolUsedSecCnt The number of used sectors on the volume. VolTotSecCnt The total number of sectors on the volume. NOTES None. 496 600-uC-FS-001.book Page 497 Wednesday, October 10, 2012 12:03 PM Appendix E C/FS Configuration C/FS is configurable at compile time via approximately 30 #defines in an application's fs_cfg.h file. C/FS uses #defines because they allow code and data sizes to be scaled at compile time based on enabled features. In other words, this allows the ROM and RAM footprints of C/FS to be adjusted based on your requirements. Most of the #defines should be configured with the default configuration values. This leaves about a dozen or so values that should be configured with values that may deviate from the default configuration. 497 600-uC-FS-001.book Page 498 Wednesday, October 10, 2012 12:03 PM Appendix E E-1 FILE SYSTEM CONFIGURATION Core file system modules may be selectively disabled. FS_CFG_BUILD FS_CFG_BUILD selects the file system build. Should always be set to FS_BUILD_FULL in this release. FS_CFG_SYS_DRV_SEL FS_CFG_SYS_DRV_SEL selects which file system driver(s) will be included. Currently, there is only one option. When FS_SYS_DRV_SEL_FAT, the FAT system driver will be included. FS_CFG_CACHE_EN FS_CFG_CACHE_EN enables (when set to DEF_ENABLED) or disables (when set to DEF_DISABLED) code generation of volume cache functions. Function File FSVol_CacheAssign() fs_vol.c FSVol_CacheFlush() fs_vol.c FSVol_CacheInvalidate() fs_vol.c Table E-1 Cache function exclusion These functions are not included if FS_CFG_CACHE_EN is DEF_DISABLED FS_CFG_BUF_ALIGN_OCTETS FS_CFG_BUF_ALIGN_OCTETS configures the minimum alignment of the internal buffers in octets. This should be set to the maximum alignment required by the any of the CPU, system buses and, if relevant, the peripherals and DMA controller involved in the file system operations. When no minimum alignment is required FS_CFG_BUF_ALIGN_OCTETS should generally be set to the platform natural alignment for performance reasons. FS_CFG_API_EN FS_CFG_API_EN enables (when set to DEF_ENABLED) or disables (when set to DEF_DISABLED) code generation of the POSIX API functions. This API includes functions like fs_fopen() or fs_opendir() which mirror standard POSIX functions like fopen() or opendir(). 498 600-uC-FS-001.book Page 499 Wednesday, October 10, 2012 12:03 PM FS_CFG_DIR_EN FS_CFG_DIR_EN enables (when set to DEF_ENABLED) or disables (when set to DEF_DISABLED) code generation of directory access functions. When disabled, the functions in the following table will not be available. Function File fs_opendir() fs_api.c fs_closedir() fs_api.c fs_readdir_r() fs_api.c FSDir_Open() fs_dir.c FSDir_Close() fs_dir.c FSDir_Rd() fs_dir.c Table E-2 Directory function exclusion These functions are not included if FS_CFG_DIR_EN is DEF_DISABLED 499 600-uC-FS-001.book Page 500 Wednesday, October 10, 2012 12:03 PM Appendix E E-2 FEATURE INCLUSION CONFIGURATION Individual file system features may be selectively disabled. FS_CFG_FILE_BUF_EN FS_CFG_BUF_EN enables (when set to DEF_ENABLED) or disables (when set to DEF_DISABLED) code generation of file buffer functions. When disabled, the functions in the following table will not be available. Function File fs_fflush() fs_api.c fs_setbuf() fs_api.c fs_setvbuf() fs_api.c FSFile_BufAssign() fs_file.c FSFile_BufFlush() fs_file.c Table E-3 File buffer function exclusion These functions are not included if FS_CFG_FILE_BUF_EN is DEF_DISABLED FS_CFG_FILE_LOCK_EN FS_CFG_FILE_LOCK_EN enables (when set to DEF_ENABLED) or disables (when set to DEF_DISABLED) code generation of file lock functions. When enabled, a file can be locked across several operations; when disabled, a file is only locked during a single operation and the functions in the following table will not be available. Function File fs_flockfile() fs_api.c fs_funlockfile() fs_api.c fs_ftrylockfile() fs_api.c FSFile_LockGet() fs_file.c FSFile_LockSet() fs_file.c FSFile_LockAccept() fs_file.c Table E-4 File lock function exclusion These functions are not included if FS_CFG_FILE_LOCK_EN is DEF_DISABLED 500 600-uC-FS-001.book Page 501 Wednesday, October 10, 2012 12:03 PM FS_CFG_PARTITION_EN When FS_CFG_PARTITION_EN is enabled (DEF_ENABLED). volumes can be opened on secondary partitions and partitions can be created. When it is disabled (DEF_DISABLED), volumes can be opened only on the first partition and the functions in the following table will not be available. The function FSDev_PartitionInit(), which initializes the partition structure on a volume, will be included in both configurations. Function File FSDev_GetNbrPartitions() fs_dev.c FSDev_PartitionAdd() fs_dev.c FSDev_PartitionFind() fs_dev.c Table E-5 Partition function exclusion These functions are not included if FS_CFG_PARTITION_EN is DEF_DISABLED. FS_CFG_WORKING_DIR_EN When FS_CFG_WORKING_DIR_EN is enabled (DEF_ENABLED), file system operations can be performed relative to a working directory. When it is disabled (DEF_DISABLED), all file system operations must be performed on absolute paths and the functions in the following table will not be available. Function File fs_chdir() fs_api.c fs_getcwd() fs_api.c FS_WorkingDirGet() fs.h FS_WorkingDirSet() fs.h Table E-6 Working directory function exclusion These functions are not included if FS_CFG_WORKING_DIR_EN is DEF_DISABLED 501 600-uC-FS-001.book Page 502 Wednesday, October 10, 2012 12:03 PM Appendix E FS_CFG_UTF8_EN FS_CFG_UTF8_EN selects whether file names may be specified in UTF-8. When enabled (DEF_ENABLED), file names may be specified in UTF-8; when disabled (DEF_DISABLED), file names must be specified in ASCII. FS_CFG_CONCURRENT_ENTRIES_ACCESS_EN FS_CFG_CONCURRENT_ENTRIES_ACCESS_EN selects whether one file can be open multiple times (in one or more task). When enabled (DEF_ENABLED), files may be open concurrently multiple times and without protection. When disabled (DEF_DISABLED), files may be open concurrently only in read-only mode, but may not be open concurrently in write mode. This option makes the file system safer when disabled. FS_CFG_RD_ONLY_EN FS_CFG_RD_ONLY_EN selects whether write access to files, volumes and devices will be possible. When DEF_ENABLED, files, volumes and devices may only be read--code for write operations will not be included and the functions in the following table will not be available. Function File fs_fwrite() fs_api.c fs_remove() fs_api.c fs_rename() fs_api.c fs_mkdir() fs_api.c fs_truncate() fs_api.c fs_rmdir() fs_api.c FSDev_PartitionAdd() fs_dev.c FSDev_PartitionInit() fs_dev.c FSDev_Wr() fs_dev.c FSEntry_AttribSet() fs_entry.c FSEntry_Copy() fs_entry.c FSEntry_Create() fs_entry.c FSEntry_TimeSet() fs_entry.c FSEntry_Del() fs_entry.c FSEntry_Rename() fs_entry.c 502 600-uC-FS-001.book Page 503 Wednesday, October 10, 2012 12:03 PM Function File FSFile_Truncate() fs_file.c FSFile_Wr() fs_file.c FSVol_Fmt() fs_vol.c FSVol_LabelSet() fs_vol.c FSVol_Wr() fs_vol.c Table E-7 Read only function exclusion (continued) These functions are not included if FS_CFG_RD_ONLY_EN is DEF_ENABLED FS_CFG_64_BITS_LBA_EN FS_CFG_64_BIT_LBA_EN selects whether support for 64 logical block addressing (LBA) is enabled. When DEF_ENABLED support 64-bit LBA will be included otherwise LBA will be limited to 32 bit. Applications that need support for 48-bit LBA should set this feature to DEF_ENABLED. E-3 NAME RESTRICTION CONFIGURATION Individual file system features may be selectively disabled. FS_CFG_MAX_PATH_NAME_LEN FS_CFG_MAX_PATH_NAME_LEN configures the maximum path name length, in characters (not including the final NULL character). The default value is 260 (the maximum path name length for paths on FAT volumes). FS_CFG_MAX_FILE_NAME_LEN FS_CFG_MAX_FILE_NAME_LEN configures the maximum file name length, in characters (not including the final NULL character). The default value is 255 (the maximum file name length for FAT long file names). FS_CFG_MAX_DEV_DRV_NAME_LEN FS_CFG_MAX_DEV_DRV_NAME_LEN configures the maximum device driver name length, in characters (not including the final NULL character). The default value is 10. 503 600-uC-FS-001.book Page 504 Wednesday, October 10, 2012 12:03 PM Appendix E FS_CFG_MAX_DEV_NAME_LEN FS_CFG_MAX_DEV_NAME_LEN configures the maximum device name length, in characters (not including the final NULL character). The default value is 15. FS_CFG_MAX_VOL_NAME_LEN FS_CFG_MAX_VOL_NAME_LEN configures the maximum volume name length, in characters (not including the final NULL character). The default value is 10. E-4 DEBUG CONFIGURATION A fair amount of code in C/FS has been included to simplify debugging. There are several configuration constants used to aid debugging. FS_CFG_DBG_MEM_CLR_EN FS_CFG_DBG_MEM_CLR_EN is used to clear internal file system data structures when allocated or deallocated. When DEF_ENABLED, internal file system data structures will be cleared. FS_CFG_DBG_WR_VERIFY_EN FS_CFG_DBG_WR_VERIFY_EN is used verify writes by reading back data. This is a particularly convenient feature while debugging a driver. E-5 ARGUMENT CHECKING CONFIGURATION Most functions in C/FS include code to validate arguments that are passed to it. Specifically, C/FS checks to see if passed pointers are NULL, if arguments are within valid ranges, etc. The following constants configure additional argument checking. FS_CFG_ARG_CHK_EXT_EN FS_CFG_ARG_CHK_EXT_EN allows code to be generated to check arguments for functions that can be called by the user and for functions which are internal but receive arguments from an API that the user can call. FS_CFG_ARG_CHK_DBG_EN FS_CFG_ARG_CHK_DBG_EN allows code to be generated which checks to make sure that pointers passed to functions are not NULL, that arguments are within range, etc.: 504 600-uC-FS-001.book Page 505 Wednesday, October 10, 2012 12:03 PM E-6 FILE SYSTEM COUNTER CONFIGURATION C/FS contains code that increments counters to keep track of statistics such as the number of packets received, the number of packets transmitted, etc. Also, C/FS contains counters that are incremented when error conditions are detected. FS_CFG_CTR_STAT_EN FS_CFG_CTR_STAT_EN determines whether the code and data space used to keep track of statistics will be included. When DEF_ENABLED, statistics counters will be maintained. FS_CFG_CTR_ERR_EN FS_CFG_CTR_STAT_EN determines whether the code and data space used to keep track of errors will be included. When DEF_ENABLED, error counters will be maintained. E-7 FAT CONFIGURATION Configuration constants can be used to enable/disable features within the FAT file system driver. FS_FAT_CFG_LFN_EN FS_FAT_CFG_LFN_EN is used to control whether long file names (LFNs) are supported. When DEF_DISABLED, all file names must be valid 8.3 short file names. FS_FAT_CFG_FAT12_EN FS_FAT_CFG_FAT12_EN is used to control whether FAT12 is supported. When DEF_DISABLED, FAT12 volumes can not be opened, nor can a device be formatted as a FAT12 volume. FS_FAT_CFG_FAT16_EN FS_FAT_CFG_FAT16_EN is used to control whether FAT16 is supported. When DEF_DISABLED, FAT16 volumes can not be opened, nor can a device be formatted as a FAT16 volume. FS_FAT_CFG_FAT32_EN FS_FAT_CFG_FAT32_EN is used to control whether FAT32 is supported. When DEF_DISABLED, FAT32 volumes can not be opened, nor can a device be formatted as a FAT32 volume. 505 600-uC-FS-001.book Page 506 Wednesday, October 10, 2012 12:03 PM Appendix E FS_FAT_CFG_JOURNAL_EN FS_FAT_CFG_JOURNAL_EN selects whether journaling functions will be present. When DEF_ENABLED, journaling functions are present; when DEF_DISABLED, journaling functions are NOT present. If disabled, the functions in Table E-8 will not be available. Function File FS_FAT_JournalOpen() fs_fat_journal.c/.h FS_FAT_JournalClose() fs_fat_journal.c/.h FS_FAT_JournalStart() fs_fat_journal.c/.h FS_FAT_JournalEnd() fs_fat_journal.c/.h Table E-8 Journaling function exclusion These functions are NOT included if FS_FAT_CFG_JOURNAL_EN is DEF_DISABLED FS_FAT_CFG_VOL_CHK_EN FS_FAT_CFG_VOL_CHK_EN selects whether volume check is supported. When DEF_ENABLED, volume check is supported; when DEF_DISABLED, the function FS_FAT_VolChk() will not be available. FS_FAT_CFG_VOL_CHK_MAX_LEVELS FS_FAT_CFG_VOL_CHK_MAX_LEVELS specifies the maximum number of directory levels that will be checked by the volume check function. Each level requires an additional 12 bytes stack space. E-8 SD/MMC SPI CONFIGURATION FS_DEV_SD_SPI_CFG_CRC_EN Data blocks received from the card are accompanied by CRCs, as are the blocks transmitted to the card. FS_DEV_SD_SPI_CFG_CRC_EN enables CRC validation by the card, as well as the generation and checking of CRCs. If DEF_ENABLED, CRC generation and checking will be performed. 506 600-uC-FS-001.book Page 507 Wednesday, October 10, 2012 12:03 PM E-9 TRACE CONFIGURATION The file system debug trace is enabled by #define`ing FS_TRACE_LEVEL in your application's fs_cfg.h: #define FS_TRACE_LEVEL TRACE_LEVEL_DBG The valid trace levels are described in the table below. A trace functions should also be defined: #define FS_TRACE printf This should be a printf-type function that redirects the trace output to some accessible terminal (for example, the terminal I/O window within your debugger, or a serial port) . When porting a driver to a new platform, this information can be used to debug the fledgling port. Trace Level Meaning TRACE_LEVEL_OFF No trace. TRACE_LEVEL_INFO Basic event information (e.g., volume characteristics). TRACE_LEVEL_DBG Debug information. TRACE_LEVEL_LOG Event log. Table E-9 Trace levels 507 600-uC-FS-001.book Page 508 Wednesday, October 10, 2012 12:03 PM Appendix E 508 600-uC-FS-001.book Page 509 Wednesday, October 10, 2012 12:03 PM Appendix F Shell Commands The command line interface is a traditional method for accessing the file system on a remote system, or in a device with a serial port (be that RS-232 or USB). A group of shell commands, derived from standard UNIX equivalents, are available for C/FS. These may simply expedite evaluation of the file system suite, or become part a primary method of access (or gathering debug information) in your final product. Figure F-1 C/FS shell command usage 509 600-uC-FS-001.book Page 510 Wednesday, October 10, 2012 12:03 PM Appendix F F-1 FILES AND DIRECTORIES C/FS with the shell commands (and C/Shell) is organized into the directory structure shown in Figure F-2. The files constituting the shell commands ares outlined in this section; the generic file-system files, outlined in Chapter 3, "C/FS Directories and Files" on page 29, are also required. Figure F-2 Directory structure \Micrium\Software\uC-FS\Cmd fs_shell.* contain the shell commands for C/FS. \Micrium\Software\uC-FS\Cmd\Template\Cfg fs_shell_cfg.h is the template configuration file for the C/FS shell commands. This file should be copied to your application directory and modified. \Micrium\Software\uC-Shell This directory contains C/Shell, which is used to process the commands. See the C/Shell user manual for more information. 510 600-uC-FS-001.book Page 511 Wednesday, October 10, 2012 12:03 PM F-2 USING THE SHELL COMMANDS To use shell commands, four files, in addition to the generic file system files, must be included in the build: fs_shell.c fs_shell.h shell.c (located in \Micrium\Software\uC-Shell\Source) shell.h (located in \Micrium\Software\uC-Shell\Source) The file fs_shell.h and shell.h must also be #included in any application or header files initialize C/Shell or handle shell commands. The shell command configuration file (fs_shell_cfg.h) should be copied to your application directory and modified. The following directories must be on the project include path: \Micrium\Software\uC-FS\Cmd \Micrium\Software\uC-Shell\Source C/Shell with the C/FS shell commands is initialized in Listing F-1. The file system initialization (FS_Init()) function should have previously been called. CPU_BOOLEAN App_ShellInit (void) { CPU_BOOLEAN ok; ok = Shell_Init(); if (ok == DEF_FAIL) { return (DEF_FAIL); } ok = FSShell_Init(); if (ok == DEF_FAIL) { return (DEF_FAIL; } return (DEF_OK); } Listing F-1 Initializing C/Shell 511 600-uC-FS-001.book Page 512 Wednesday, October 10, 2012 12:03 PM Appendix F It's assumed that the application will create a task to receive input from a terminal; this task should be written as shown in Listing F-2. void App_ShellTask (void *p_arg) { CPU_CHAR cmd_line[MAX_CMD_LEN]; SHELL_ERR SHELL_CMD_PARAM CPU_CHAR err; cmd_param; cwd_path[FS_CFG_FULL_ NAME_LEN + 1u]; /* Init cmd param (see Note #1). */ Str_Copy(&cwd_path[0], (CPU_CHAR *)"\\"); cmd_param.pcur_working_dir = (void *)cwd_path[0]; cmd_param.pout_opt = (void *)0; while (DEF_TRUE) { App_ShellIn(cmd_line, MAX_CMD_LEN); /* Rd cmd /* Exec cmd (see Note #2). */ (see Note #3). */ Shell_Exec(cmd_line, App_ShellOut, &cmd_param, &err); switch (err) { case SHELL_ERR_CMD_NOT_FOUND: case SHELL_ERR_CMD_SEARCH: case SHELL_ERR_ARG_TBL_FULL: App_ShellOut("Command not found\r\n", 19, cmd_param.pout_opt); break; default: break; } } } /* ************************************************************************************** * App_ShellIn() ******************************************************************************1******* */ CPU_INT16S App_ShellIn (CPU_CHAR *pbuf, CPU_INT16U buf_len) { /* $$$$ Store line from terminal/command line into `pbuf'; return length of line. */ } 512 600-uC-FS-001.book Page 513 Wednesday, October 10, 2012 12:03 PM /* ************************************************************************************** * App_ShellOut() ******************************************************************************1******* */ CPU_INT16S App_ShellOut (CPU_CHAR *pbuf, CPU_INT16U buf_len, void *popt) { /* $$$$ Output `pbuf' data on terminal/command line; return nbr bytes tx'd. */ } Listing F-2 Executing shell commands & handling shell output LF-2(1) The SHELL_CMD_PARAM structure that will be passed to Shell_Exec() must be initialized. The pcur_working_dir member must be assigned a pointer to a string of at least FS_SHELL_CFG_MAX_PATH_LEN characters. This string must have been initialized to the default working directory path; if the root directory, "\". LF-2(2) The next command, ending with a newline, should be read from the command line. LF-2(3) The received command should be executed with Shell_Exec(). If the command is a valid command, the appropriate command function will be called. For example, the command "fs_ls" will result in FSShell_ls() in fs_shell.c being called. FSShell_ls() will then print the entries in the working directory to the command line with the output function App_ShellOut(), passed as the second argument of Shell_Exec(). 513 600-uC-FS-001.book Page 514 Wednesday, October 10, 2012 12:03 PM Appendix F F-3 COMMANDS The supported commands, listed in the table below, are equivalent to the standard UNIX commands of the same names, though the functionality is typically simpler, with few or no special options. Command Description fs_cat Print file contents to the terminal output. fs_cd Change the working directory. fs_cp Copy a file. fs_date Write the date and time to terminal output, or set the system date and time fs_df Report disk free space. fs_ls List directory contents. fs_mkdir Make a directory. fs_mkfs Format a volume. fs_mount Mount volume. fs_mv Move files. fs_od Dump file contents to terminal output. fs_pwd Write to terminal output pathname of current working directory. fs_rm Remove a directory entry. fs_rmdir Remove a directory. fs_touch Change file modification time. fs_umount Unmount volume. fs_wc Determine the number of newlines, words and bytes in a file. Table F-1 Commands Information about each command can be obtained using the help (-h) option: Figure F-3 Help option output 514 600-uC-FS-001.book Page 515 Wednesday, October 10, 2012 12:03 PM F-3-1 fs_cat Print file contents to the terminal output. USAGES fs_cat [file] ARGUMENTS file Path of file to print to terminal output. OUTPUT File contents, in the ASCII character set. Non-printable/non-space characters are transmitted as full stops ("periods", character code 46). For a more convenient display of binary files use fs_od. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_CAT_EN is DEF_ENABLED. NOTES/WARNINGS None. 515 600-uC-FS-001.book Page 516 Wednesday, October 10, 2012 12:03 PM Appendix F F-3-2 fs_cd Change the working directory. USAGES fs_cd [dir] ARGUMENTS dir Absolute directory path. OR Path relative to current working directory. OUTPUT None. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_CD_EN is DEF_ENABLED. NOTES/WARNINGS The new working directory is formed in three steps: 1 516 If the argument dir begins with the path separator character (slash, `\') or a volume name, it will be interpreted as an absolute directory path and will become the preliminary working directory. Otherwise the preliminary working directory path is formed by the concatenation of the current working directory, a path separator character and dir. 600-uC-FS-001.book Page 517 Wednesday, October 10, 2012 12:03 PM 2 The preliminary working directory path is then refined, from the first to last path component: a. If the component is a `dot' component, it is removed b. If the component is a `dot dot' component, and the preliminary working directory path is not NULL, the previous path component is removed. In any case, the `dot dot' component is removed. c. Trailing path separator characters are removed, and multiple path separator characters are replaced by a single path separator character. 3 The volume is examined to determine whether the preliminary working directory exists. If it does, it becomes the new working directory. Otherwise, an error is output, and the working directory is unchanged. 517 600-uC-FS-001.book Page 518 Wednesday, October 10, 2012 12:03 PM Appendix F F-3-3 fs_cp Copy a file. USAGES fs_cp [source_file] [dest_file] fs_cp [source_file] [dest_dir] ARGUMENTS source_file Source file path. dest_file Destination file path. dest_dir Destination directory path. OUTPUT None. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_CP_EN is DEF_ENABLED and FS_CFG_RD_ONLY_EN is DEF_DISABLED. NOTES/WARNINGS In the first form of this command, neither argument may be an existing directory. The contents of source_file will be copied to a file named dest_file located in the same directory as source_file. In the second form of this command, the first argument must not be an existing directory and the second argument must be an existing directory. The contents of source_file will be copied to a file with name formed by concatenating dest_dir, a path separator character and the final component of source_file. 518 600-uC-FS-001.book Page 519 Wednesday, October 10, 2012 12:03 PM F-3-4 fs_date Write the date and time to terminal output, or set the system date and time. USAGES fs_date fs_date [time] ARGUMENTS time If specified, time to set, in the form mmddhhmmccyy: 1st mm dd hh 2nd mm ccyy the the the the the month (1-12) day (1-29, 30 or 31) hour (0-23) minute (0-59) year (1900 or larger) OUTPUT If no argument, date and time. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_DATE_EN is DEF_ENABLED. NOTES/WARNINGS None. Figure F-4 fs_date output 519 600-uC-FS-001.book Page 520 Wednesday, October 10, 2012 12:03 PM Appendix F F-3-5 fs_df Report disk free space. USAGES fs_df fs_df [vol] ARGUMENTS vol If specified, volume on which to report free space. Otherwise, information about all volumes will be output.. OUTPUT Name, total space, free space and used space of volumes. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_DF_EN is DEF_ENABLED. NOTES/WARNINGS None. Figure F-5 fs_df output 520 600-uC-FS-001.book Page 521 Wednesday, October 10, 2012 12:03 PM F-3-6 fs_ls List directory contents. USAGES fs_ls ARGUMENTS None. OUTPUT List of directory contents. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_LS_EN is DEF_ENABLED. NOTES/WARNINGS The output resembles the output from the standard UNIX command ls -l. See the figure below. Figure F-6 fs_ls output 521 600-uC-FS-001.book Page 522 Wednesday, October 10, 2012 12:03 PM Appendix F F-3-7 fs_mkdir Make a directory. USAGES fs_mkdir [dir] ARGUMENTS dir Directory path. OUTPUT None. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_MKDIR_EN is DEF_ENABLED and FS_CFG_RD_ONLY_EN is DEF_DISABLED. NOTES/WARNINGS None. 522 600-uC-FS-001.book Page 523 Wednesday, October 10, 2012 12:03 PM F-3-8 fs_mkfs Format a volume. USAGES fs_mkfs [vol] ARGUMENTS vol Volume name. OUTPUT None. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_MKFS_EN is DEF_ENABLED and FS_CFG_RD_ONLY_EN is DEF_DISABLED. NOTES/WARNINGS None. 523 600-uC-FS-001.book Page 524 Wednesday, October 10, 2012 12:03 PM Appendix F F-3-9 fs_mount Mount volume. USAGES fs_mount [dev] [vol] ARGUMENTS dev Device to mount. vol Name which will be given to volume. OUTPUT None. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_MOUNT_EN is DEF_ENABLED. NOTES/WARNINGS None. 524 600-uC-FS-001.book Page 525 Wednesday, October 10, 2012 12:03 PM F-3-10 fs_mv Move files. USAGES fs_mv [source_entry] [dest_entry] fs_mv [source_entry] [dest_dir] ARGUMENTS source_entry Source entry path. dest_entry Destination entry path. dest_dir Destination directory path. OUTPUT None. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_MV_EN is DEF_ENABLED and FS_CFG_RD_ONLY_EN is DEF_DISABLED. NOTES/WARNINGS In the first form of this command, the second argument must not be an existing directory. The file source_entry will be renamed dest_entry. In the second form of this command, the second argument must be an existing directory. source_entry will be renamed to an entry with name formed by concatenating dest_dir, a path separator character and the final component of source_entry. In both forms, if source_entry is a directory, the entire directory tree rooted at source_entry will be copied and then deleted. Additionally, both source_entry and dest_entry or dest_dir must specify locations on the same volume. 525 600-uC-FS-001.book Page 526 Wednesday, October 10, 2012 12:03 PM Appendix F F-3-11 fs_od Dump file contents to the terminal output. USAGES fs_od [file] ARGUMENTS file Path of file to dump to terminal output. OUTPUT File contents, in hexadecimal form. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_OD_EN is DEF_ENABLED. NOTES/WARNINGS None. Figure F-7 fs_od output 526 600-uC-FS-001.book Page 527 Wednesday, October 10, 2012 12:03 PM F-3-12 fs_pwd Write to terminal output pathname of current working directory. USAGES fs_pwd ARGUMENTS None. OUTPUT Pathname of current working directory.. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_PWD_EN is DEF_ENABLED. NOTES/WARNINGS None. 527 600-uC-FS-001.book Page 528 Wednesday, October 10, 2012 12:03 PM Appendix F F-3-13 fs_rm Remove a file. USAGES fs_rm [file] ARGUMENTS file File path. OUTPUT None. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_RM_EN is DEF_ENABLED and FS_CFG_RD_ONLY_EN is DEF_DISABLED. NOTES/WARNINGS None. 528 600-uC-FS-001.book Page 529 Wednesday, October 10, 2012 12:03 PM F-3-14 fs_rmdir Remove a directory. USAGES fs_rmdir [dir] ARGUMENTS dir Directory path. OUTPUT None. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_RMDIR_EN is DEF_ENABLED and FS_CFG_RD_ONLY_EN is DEF_DISABLED. NOTES/WARNINGS None. 529 600-uC-FS-001.book Page 530 Wednesday, October 10, 2012 12:03 PM Appendix F F-3-15 fs_touch Change file modification time. USAGES fs_touch [file] ARGUMENTS file File path. OUTPUT None. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_TOUCH_EN is DEF_ENABLED and FS_CFG_RD_ONLY_EN is DEF_DISABLED. NOTES/WARNINGS The file modification time is set to the current time. 530 600-uC-FS-001.book Page 531 Wednesday, October 10, 2012 12:03 PM F-3-16 fs_umount Unount volume. USAGES fs_umount [vol] ARGUMENTS vol Volume to unmount. OUTPUT None. REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_UMOUNT_EN is DEF_ENABLED. NOTES/WARNINGS None. 531 600-uC-FS-001.book Page 532 Wednesday, October 10, 2012 12:03 PM Appendix F F-3-17 fs_wc Determine the number of newlines, words and bytes in a file. USAGES fs_wc [file] ARGUMENTS file Path of file to examine. OUTPUT Number of newlines, words and bytes; equivalent to: printf("%d %d %d %s", newline_cnt, word_cnt, byte_cnt, file); REQUIRED CONFIGURATION Available only if FS_SHELL_CFG_WC_EN is DEF_ENABLED. NOTES/WARNINGS None. Figure F-8 fs_wc output 532 600-uC-FS-001.book Page 533 Wednesday, October 10, 2012 12:03 PM F-4 CONFIGURATION Configuration constants can be used to enable/disable features within the C/FS shell commands. FS_SHELL_CFG_BUF_LEN FS_FAT_CFG_BUF_LEN defines the length of the buffer, in octets, used to read/write from files during file access operations. Since this buffer is placed on the task stack, the task stack must be sized appropraitely. FS_SHELL_CFG_CMD_####_EN Each FS_FAT_CFG_CMD_####_EN separately command: enables/disables FS_FAT_CFG_CMD_CAT_EN Enable/disable fs_cat. FS_FAT_CFG_CMD_CD_EN Enable/disable fs_cd. FS_FAT_CFG_CMD_CP_EN Enable/disable fs_cp. FS_FAT_CFG_CMD_DF_EN Enable/disable fs_df. FS_FAT_CFG_CMD_DATE_EN Enable/disable fs_date. FS_FAT_CFG_CMD_LS_EN Enable/disable fs_ls. FS_FAT_CFG_CMD_MKDIR_EN Enable/disable fs_mkdir. FS_FAT_CFG_CMD_MKFS_EN Enable/disable fs_mkfs. FS_FAT_CFG_CMD_MOUNT_EN Enable/disable fs_mount. FS_FAT_CFG_CMD_MV_EN Enable/disable fs_mv. FS_FAT_CFG_CMD_OD_EN Enable/disable fs_od. FS_FAT_CFG_CMD_PWD_EN Enable/disable fs_pwd. a particular fs_#### 533 600-uC-FS-001.book Page 534 Wednesday, October 10, 2012 12:03 PM Appendix F FS_FAT_CFG_CMD_RM_EN Enable/disable fs_rm. FS_FAT_CFG_CMD_RMDIR_EN Enable/disable fs_rmdir. FS_FAT_CFG_CMD_TOUCH_EN Enable/disable fs_touch. FS_FAT_CFG_CMD_UMOUNT_EN Enable/disable fs_umount. FS_FAT_CFG_CMD_WC_EN Enable/disable fs_wc. 534 600-uC-FS-001.book Page 535 Wednesday, October 10, 2012 12:03 PM Appendix G Bibliography Labrosse, Jean J. 2009, C/OS-III, The Real-Time Kernel, Micrium Press, 2009, ISBN 978-0-98223375-3-0. Legare, Christian 2010, C/TCP-IP, The Embedded Protocol Stack, Micrium Press, 2010, ISBN 978-0-98223375-0-9. POSIX:2008 The Open Group Base Specifications Issue 7, IEEE Standard 1003.1-2008. Programming Lauguages -- C, ISO/IEC 9899:1999. The Motor Industry Software Reliability Association, MISRA-C:2004, Guidelines for the Use of the C Language in Critical Systems, October 2004. www.misra-c.com. http://www.clusterbuilder.org/ Cho, H., Shin, D., Eom, Y. I. 2009, KAST: K-Associative Sector Translation for NAND Flash Memory in Real-Time Systems, Architecture, 507-512. IEEE. 535 600-uC-FS-001.book Page 536 Wednesday, October 10, 2012 12:03 PM Appendix G 536 600-uC-FS-001.book Page 537 Wednesday, October 10, 2012 12:03 PM Appendix H C/FS Licensing Policy H-1 C/FS LICENSING H-1-1 C/FS SOURCE CODE This book contains C/FS precompiled in linkable object form, an evaluation board and tools (compiler/assembler/linker/debugger). Use C/FS for free, as long as it is only used with the evaluation board that accompanies this book. You will need to purchase a license when using this code in a commercial product, where the intent is to make a profit. Users do not pay anything beyond the price of the book, evaluation board and tools, as long as they are used for educational purposes. You will need to license C/FS if you intend to use C/FS in a commercial product where you intend to make a profit. You need to purchase this license when you make the decision to use C/FS in a design, not when you are ready to go to production. If you are unsure about whether you need to obtain a license for your application, please contact Micrim and discuss your use with a sales representative. CONTACT MICRIUM Micrim 1290 Weston Road, Suite 306 Weston, FL 33326 +1 954 217 2036 +1 954 217 2037 (FAX) E-Mail: sales@Micrim.com Website: www.Micrim.com 537 600-uC-FS-001.book Page 538 Wednesday, October 10, 2012 12:03 PM Appendix H H-1-2 C/FS MAINTENANCE RENEWAL Licensing C/FS provides one year of limited technical support and maintenance and source code updates. Renew the maintenance agreement for continued support and source code updates.Contact sales@Micrim.com for additional information. H-1-3 C/FS SOURCE CODE UPDATES If you are under maintenance, you will be automatically emailed when source code updates become available. You can then download your available updates from the Micrim FTP server. If you are no longer under maintenance, or forget your Micrim FTP username or password, please contact sales@Micrim.com. H-1-4 C/FS SUPPORT Support is available for licensed customers. Please visit the customer support section in www.Micrim.com. If you are not a current user, please register to create your account. A web form will be offered to you to submit your support question, Licensed customers can also use the following contact: CONTACT MICRIUM Micrium 1290 Weston Road, Suite 306 Weston, FL 33326 +1 954 217 2036 +1 954 217 2037 (FAX) 538 Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Analog Devices Inc.: AD-UCFS-SPRD