C/ FS TM The Embedded File System User's Manual V4.04 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 capatilization preference. Readers should contact the appropriate companies for more complete information on trademarks and trademark registrations. All trademarks and registerd trademarks in this book are the property of their respective holders. Copyright (c) 2010 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 and ommissions. 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 Table of Contents Chapter 1 1-1 1-2 1-3 1-4 1-5 Introduction .......................................................................................... 15 What Is a File System? ........................................................................ 15 C/FS .................................................................................................... 16 Typical Usages ..................................................................................... 17 Why FAT? ............................................................................................. 18 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 .............................................................................. 22 Architecture Components ................................................................... 24 Your Application ................................................................................... 24 LIB (Libraries) ....................................................................................... 24 POSIX API Layer .................................................................................. 24 FS Layer ............................................................................................... 24 File System Driver Layer ...................................................................... 26 Device Driver Layer .............................................................................. 26 CPU Layer ............................................................................................ 26 RTOS Layer .......................................................................................... 27 Chapter 3 3-1 3-2 3-3 3-4 3-5 3-6 3-7 3-8 3-9 3-10 Directories and Files ............................................................................ 28 Application Code ................................................................................. 31 CPU ....................................................................................................... 33 Board Support Package (BSP) ............................................................ 34 C/CPU, CPU Specific Source Code .................................................. 35 C/LIB, Portable Library Functions ..................................................... 37 C/Clk, Time/Calendar Management .................................................. 38 C/CRC, Checksums and Error Correction Codes ............................ 40 C/FS Platform-Independent Source Code ........................................ 42 C/FS FAT Filesystem Source Code ................................................... 45 C/FS Memory Device Drivers ............................................................ 46 3 3-11 3-12 3-13 C/FS Platform-Specific Source Code ............................................... 50 C/FS OS Abstraction Layer ............................................................... 51 Summary .............................................................................................. 52 Chapter 4 4-1 4-2 4-3 4-4 4-5 Miscellaneous ...................................................................................... 59 Nomenclature ....................................................................................... 59 C/FS Device and Volume Names ...................................................... 61 C/FS File and Directory Names and Paths ....................................... 62 C/FS Name Lengths ........................................................................... 63 Resource Usage ................................................................................... 65 Chapter 5 5-1 5-2 5-3 5-4 5-5 5-6 5-7 5-7-1 5-7-2 Devices and Volumes .......................................................................... 67 Device Operations ............................................................................... 68 Using Devices ...................................................................................... 69 Using Removable Devices ................................................................... 71 Partitions .............................................................................................. 72 Volume Operations .............................................................................. 76 Using Volumes ..................................................................................... 77 Using Volume Cache ............................................................................ 79 Choosing Cache Parameters ............................................................... 80 Other Caching & Buffering Mechanisms ............................................. 82 Chapter 6 6-1 6-2 6-3 6-3-1 6-3-2 6-3-3 6-3-4 6-3-5 6-4 6-5 POSIX API ............................................................................................. 83 Supported Functions ........................................................................... 84 Working Directory Functions ............................................................... 85 File Access Functions .......................................................................... 86 Opening, Reading & Writing Files ....................................................... 87 Getting or Setting the File Position ..................................................... 90 Configuring a File Buffer ...................................................................... 91 Diagnosing a File Error ........................................................................ 93 Atomic File Operations Using File Lock .............................................. 93 Directory Access Functions ................................................................ 94 Entry Access Functions ....................................................................... 96 Chapter 7 7-1 7-1-1 Files ...................................................................................................... 97 File Access Functions .......................................................................... 98 Opening Files ....................................................................................... 99 4 7-1-2 7-1-3 7-1-4 7-1-5 7-2 7-2-1 7-2-2 7-2-3 Getting Information About a File ....................................................... 100 Configuring a File Buffer .................................................................... 101 File Error Functions ............................................................................ 102 Atomic File Operations Using File Lock ............................................ 102 Entry Access Functions ..................................................................... 103 File and Directory Attributes .............................................................. 104 Creating New Files and Directories ................................................... 105 Deleting Files and Directories ........................................................... 106 Chapter 8 8-1 Directories .......................................................................................... 107 Directory Access Functions .............................................................. 108 Chapter 9 9-1 9-1-1 9-1-2 9-1-3 9-1-4 9-2 9-2-1 9-2-2 9-2-3 File Systems: FAT .............................................................................. 109 FAT Architecture ................................................................................ 110 FAT12 / FAT16 / FAT32 ...................................................................... 111 Short and Long File Names ............................................................... 111 Directories and Directory Entries ...................................................... 112 FAT System Driver Architecture ........................................................ 114 Operations .......................................................................................... 115 Formatting .......................................................................................... 115 Disk Check ......................................................................................... 116 Journaling ........................................................................................... 117 Chapter 10 10-1 10-1-1 Device Drivers .................................................................................... 119 Provided Device Drivers .................................................................... 120 Driver Characterization ...................................................................... 121 Chapter 11 11-1 11-2 11-2-1 11-2-2 IDE/CF Driver ..................................................................................... 124 Files and Directories .......................................................................... 124 Using the IDE/CF Driver ..................................................................... 125 ATA (True IDE) Communication ......................................................... 128 IDE BSP Overview .............................................................................. 131 Chapter 12 Logical Device Driver ......................................................................... 133 Chapter 13 MSC Driver ......................................................................................... 134 5 13-1 13-2 Files and Directories .......................................................................... 134 Using the MSC Driver ........................................................................ 135 Chapter 14 14-1 14-2 14-3 14-3-1 14-3-2 14-3-3 14-4 14-4-1 14-4-2 14-4-3 NAND Flash Driver ............................................................................. 137 Files and Directories .......................................................................... 138 Driver & Device Characteristics ......................................................... 139 Using a NAND Device (Software ECC) .............................................. 140 Driver Architecture ............................................................................. 146 Hardware ............................................................................................ 146 NAND BSP Overview ......................................................................... 148 Physical-Layer Drivers ....................................................................... 148 FSDev_NAND_0512x08 ...................................................................... 149 FSDev_NAND_2048x08, FSDev_NAND_2048x16 ............................. 149 FSDev_NAND_AT45 ........................................................................... 150 Chapter 15 15-1 15-2 15-3 15-3-1 15-3-2 15-3-3 15-4 15-4-1 15-4-2 15-5 15-5-1 15-5-2 15-5-3 15-5-4 15-5-5 NOR Flash Driver ............................................................................... 151 Files and Directories .......................................................................... 152 Driver & Device Characteristics ......................................................... 154 Using a Parallel NOR Device ............................................................. 156 Driver Architecture ............................................................................. 160 Hardware ............................................................................................ 160 NOR BSP Overview ............................................................................ 162 Using a Serial NOR Device ................................................................ 163 Hardware ............................................................................................ 164 NOR SPI BSP Overview ..................................................................... 165 Physical-Layer Drivers ....................................................................... 166 FSDev_NOR_AMD_1x08, FSDev_NOR_AMD_1x16 .......................... 167 FSDev_NOR_Intel_1x16 ..................................................................... 167 FSDev_NOR_SST39 ........................................................................... 168 FSDev_NOR_STM25 .......................................................................... 168 FSDev_NOR_SST25 ........................................................................... 169 Chapter 16 16-1 16-2 RAM Disk Driver ................................................................................. 170 Files and Directories .......................................................................... 170 Using the RAM Disk Driver ................................................................ 171 Chapter 17 SD/MMC Drivers ................................................................................ 174 6 17-1 17-2 17-2-1 17-2-2 17-2-3 17-3 17-3-1 17-3-2 17-3-3 Files and Directories .......................................................................... 176 Using the SD/MMC CardMode Driver ............................................... 177 SD/MMC CardMode Communication ............................................... 180 SD/MMC CardMode Communication Debugging ............................ 182 SD/MMC CardMode BSP Overview .................................................. 187 Using the SD/MMC SPI Driver ........................................................... 189 SD/MMC SPI Communication ........................................................... 193 SD/MMC SPI Communication Debugging ........................................ 194 SD/MMC SPI BSP Overview .............................................................. 197 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 A-2-16 A-2-17 A-2-18 A-2-19 A-2-20 C/FS API Reference Manual ............................................................ 198 General File System Functions .......................................................... 200 FS_DevDrvAdd() ................................................................................. 201 FS_Init() ............................................................................................... 203 FS_VersionGet() .................................................................................. 204 FS_WorkingDirGet() ........................................................................... 205 FS_WorkingDirSet() ............................................................................ 206 Posix API Functions ........................................................................... 207 fs_asctime_r() ..................................................................................... 210 fs_chdir() ............................................................................................. 211 fs_clearerr() ......................................................................................... 212 fs_closedir() ........................................................................................ 213 fs_ctime_r() ......................................................................................... 214 fs_fclose() ........................................................................................... 215 fs_feof() ............................................................................................... 216 fs_ferror() ............................................................................................ 217 fs_fflush() ............................................................................................ 218 fs_fgetpos() ......................................................................................... 219 fs_flockfile() ........................................................................................ 220 fs_fopen() ............................................................................................ 221 fs_fread() ............................................................................................. 222 fs_fseek() ............................................................................................ 223 fs_fsetpos() ......................................................................................... 225 fs_ftell() ............................................................................................... 226 fs_ftruncate() ...................................................................................... 227 fs_ftrylockfile() .................................................................................... 228 fs_funlockfile() .................................................................................... 229 fs_fwrite() ............................................................................................ 230 7 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-4 A-4-1 A-4-2 A-4-3 A-4-4 A-5 A-5-1 A-5-2 A-5-3 A-5-4 A-5-5 A-5-6 fs_getcwd() ......................................................................................... 231 fs_localtime_r() ................................................................................... 232 fs_mkdir() ............................................................................................ 233 fs_mktime() ......................................................................................... 234 fs_opendir() ......................................................................................... 235 fs_readdir_r() ...................................................................................... 236 fs_remove() ......................................................................................... 237 fs_rename() ......................................................................................... 239 fs_rewind() .......................................................................................... 241 fs_rmdir() ............................................................................................. 242 fs_setbuf() ........................................................................................... 244 fs_setvbuf() ......................................................................................... 245 Device Functions ............................................................................... 247 FSDev_Close() .................................................................................... 249 FSDev_GetDevName() ....................................................................... 250 FSDev_GetDevCnt() ........................................................................... 251 FSDev_GetDevCntMax() .................................................................... 252 FSDev_GetNbrPartitions() .................................................................. 253 FSDev_Open() .................................................................................... 254 FSDev_PartitionAdd() ......................................................................... 256 FSDev_PartitionFind() ........................................................................ 257 FSDev_PartitionInit() .......................................................................... 259 FSDev_Query() ................................................................................... 261 FSDev_Rd() ......................................................................................... 262 FSDev_Refresh() ................................................................................. 264 FSDev_Wr() ......................................................................................... 266 Directory Access Functions .............................................................. 267 FSDir_Close() ...................................................................................... 268 FSDir_IsOpen() ................................................................................... 269 FSDir_Open() ...................................................................................... 270 FSDir_Rd() .......................................................................................... 272 Entry Access Functions ..................................................................... 273 FSEntry_AttribSet() ............................................................................. 274 FSEntry_Copy() .................................................................................. 276 FSEntry_Create() ................................................................................ 278 FSEntry_Del() ...................................................................................... 280 FSEntry_Query() ................................................................................. 282 FSEntry_Rename() .............................................................................. 284 8 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 A-7-11 A-7-12 A-7-13 A-7-14 A-8 A-8-1 A-8-2 A-8-3 FSEntry_TimeSet() .............................................................................. 286 File Functions ..................................................................................... 288 FSFile_BufAssign() ............................................................................. 290 FSFile_BufFlush() ............................................................................... 292 FSFile_Close() ..................................................................................... 293 FSFile_ClrErr() .................................................................................... 294 FSFile_IsEOF() .................................................................................... 295 FSFile_IsErr() ...................................................................................... 296 FSFile_IsOpen() .................................................................................. 297 FSFile_LockAccept() .......................................................................... 299 FSFile_LockGet() ................................................................................ 300 FSFile_LockSet() ................................................................................ 301 FSFile_Open() ..................................................................................... 302 FSFile_PosGet() .................................................................................. 305 FSFile_PosSet() .................................................................................. 306 FSFile_Query() .................................................................................... 308 FSFile_Rd() ......................................................................................... 309 FSFile_Truncate() ............................................................................... 311 FSFile_Wr() ......................................................................................... 312 Volume Functions .............................................................................. 314 FSVol_Close() ..................................................................................... 316 FSVol_Fmt() ........................................................................................ 317 FSVol_GetDfltVolName() .................................................................... 319 FSVol_GetVolCnt() .............................................................................. 320 FSVol_GetVolCntMax() ....................................................................... 321 FSVol_GetVolName() .......................................................................... 322 FSVol_IsDflt() ...................................................................................... 323 FSVol_IsMounted() ............................................................................. 324 FSVol_LabelGet() ................................................................................ 325 FSVol_LabelSet() ................................................................................ 327 FSVol_Open() ...................................................................................... 329 FSVol_Query() ..................................................................................... 331 FSVol_Rd() .......................................................................................... 332 FSVol_Wr() .......................................................................................... 334 Volume Cache Functions ................................................................... 335 FSVol_CacheAssign () ........................................................................ 336 FSVol_CacheInvalidate () ................................................................... 338 FSVol_CacheFlush () .......................................................................... 339 9 A-9 A-9-1 A-9-2 A-9-3 A-9-4 A-9-5 A-9-6 A-10 A-10-1 A-10-2 A-10-3 A-10-4 A-10-5 A-10-6 A-10-7 A-10-8 A-10-9 A-11 A-11-1 A-11-2 A-11-3 A-12 A-12-1 A-12-2 A-12-3 A-12-4 A-12-5 NAND Driver Functions ...................................................................... 340 FSDev_NAND_LowFmt() .................................................................... 341 FSDev_NAND_LowMount() ................................................................ 342 FSDev_NAND_LowUnmount() ........................................................... 343 FSDev_NAND_PhyRdSec() ................................................................ 344 FSDev_NAND_PhyWrSec() ................................................................ 346 FSDev_NAND_PhyEraseBlk() ............................................................ 348 NOR Driver Functions ........................................................................ 350 FSDev_NOR_LowFmt() ...................................................................... 352 FSDev_NOR_LowMount() .................................................................. 353 FSDev_NOR_LowUnmount() .............................................................. 354 FSDev_NOR_LowCompact() .............................................................. 355 FSDev_NOR_LowDefrag() .................................................................. 356 FSDev_NOR_PhyRd() ......................................................................... 357 FSDev_NOR_PhyWr() ......................................................................... 359 FSDev_NOR_PhyEraseBlk() ............................................................... 361 FSDev_NOR_PhyEraseChip() ............................................................ 363 SD/MMC Driver Functions ................................................................. 364 FSDev_SD_xxx_QuerySD() ................................................................ 365 FSDev_SD_xxx_RdCID() .................................................................... 367 FSDev_SD_xxx_RdCSD() ................................................................... 369 FAT System Driver Functions ............................................................ 370 FS_FAT_JournalOpen() ...................................................................... 371 FS_FAT_JournalClose() ...................................................................... 372 FS_FAT_JournalStart() ....................................................................... 373 FS_FAT_JournalStop() ....................................................................... 374 FS_FAT_VolChk() ................................................................................ 375 Appendix B B-1 B-2 B-3 B-4 B-5 B-6 B-7 B-8 B-9 C/FS Error Codes ............................................................................. 376 System Error Codes ........................................................................... 376 Buffer Error Codes ............................................................................. 376 Cache Error Codes ............................................................................ 377 Device Error Codes ............................................................................ 377 Device Driver Error Codes ................................................................. 378 Directory Error Codes ........................................................................ 378 ECC Error Codes ................................................................................ 378 Entry Error Codes .............................................................................. 378 File Error Codes ................................................................................. 379 10 B-10 B-11 B-12 B-13 B-14 B-15 Name Error Codes ............................................................................. 379 Partition Error Codes ......................................................................... 380 Pools Error Codes .............................................................................. 380 File System Error Codes .................................................................... 380 Volume Error Codes ........................................................................... 381 OS Layer Error Codes ........................................................................ 382 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-5-13 C-5-14 C-5-15 C-6 C-6-1 C/FS Porting Manual ........................................................................ 383 Date/Time management .................................................................... 385 CPU Port ............................................................................................. 386 OS Kernel ........................................................................................... 386 Device Driver ...................................................................................... 394 NameGet() .......................................................................................... 396 Init() ..................................................................................................... 397 Open() ................................................................................................. 398 Close() ................................................................................................. 400 Rd() ..................................................................................................... 401 Wr() ..................................................................................................... 402 Query() ................................................................................................ 404 IO_Ctrl() ............................................................................................... 406 IDE/CF Device BSP ............................................................................ 408 FSDev_IDE_BSP_Open() .................................................................... 410 FSDev_IDE_BSP_Close() ................................................................... 411 FSDev_IDE_BSP_Lock() / FSDev_IDE_BSP_Unlock() ...................... 412 FSDev_IDE_BSP_Reset() ................................................................... 413 FSDev_IDE_BSP_RegRd() ................................................................. 414 FSDev_IDE_BSP_RegWr() ................................................................. 415 FSDev_IDE_BSP_CmdWr() ................................................................ 416 FSDev_IDE_BSP_DataRd() ................................................................ 417 FSDev_IDE_BSP_DataWr() ................................................................ 418 FSDev_IDE_BSP_DMA_Start() ........................................................... 419 FSDev_IDE_BSP_DMA_End() ............................................................ 420 FSDev_IDE_BSP_GetDrvNbr() ........................................................... 422 FSDev_IDE_BSP_GetModesSupported() .......................................... 423 FSDev_IDE_BSP_SetMode() .............................................................. 424 FSDev_IDE_BSP_Dly400_ns() ............................................................ 425 NAND Flash Physical-Layer Driver .................................................... 426 Open() ................................................................................................. 429 11 C-6-2 C-6-3 C-6-4 C-6-5 C-6-6 C-6-7 C-6-8 C-6-9 C-7 C-7-1 C-7-2 C-7-3 C-7-4 C-7-5 C-7-6 C-7-7 C-7-8 C-7-9 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 C-12 C-12-1 C-12-2 C-12-3 Close() ................................................................................................. 431 RdPage() ............................................................................................. 432 RdSpare() ............................................................................................ 434 WrPage() ............................................................................................. 435 WrSpare() ............................................................................................ 436 CopyBack() ......................................................................................... 437 EraseBlk() ........................................................................................... 438 IO_Ctrl() ............................................................................................... 439 NAND Flash BSP ................................................................................ 440 FSDev_NAND_BSP_Open() ............................................................... 441 FSDev_NAND_BSP_Close() ............................................................... 442 FSDev_NAND_BSP_ChipSelEn() ....................................................... 443 FSDev_NAND_BSP_ChipSelDis() ...................................................... 444 FSDev_NAND_BSP_RdData() ............................................................ 445 FSDev_NAND_BSP_WrAddr() ............................................................ 446 FSDev_NAND_BSP_WrCmd() ............................................................ 447 FSDev_NAND_BSP_WrData() ............................................................ 448 FSDev_NAND_BSP_WaitWhileBusy() ............................................... 449 NAND Flash SPI BSP ......................................................................... 450 NOR Flash Physical-Layer Driver ...................................................... 450 Open() ................................................................................................. 453 Close() ................................................................................................. 454 Rd() ..................................................................................................... 455 Wr() ..................................................................................................... 456 EraseBlk() ........................................................................................... 457 IO_Ctrl() ............................................................................................... 458 NOR Flash BSP .................................................................................. 459 FSDev_NOR_BSP_Open() .................................................................. 460 FSDev_NOR_BSP_Close() ................................................................. 461 FSDev_NOR_BSP_Rd_XX() ................................................................ 462 FSDev_NOR_BSP_RdWord_XX() ....................................................... 463 FSDev_NOR_BSP_WrWord_XX() ....................................................... 464 FSDev_NOR_BSP_WaitWhileBusy() .................................................. 465 NOR Flash SPI BSP ........................................................................... 466 SD/MMC Cardmode BSP .................................................................. 467 FSDev_SD_Card_BSP_Open() ........................................................... 470 FSDev_SD_Card_BSP_Lock() ............................................................ 471 FSDev_SD_Card_BSP_CmdStart() .................................................... 472 12 C-12-4 C-12-5 C-12-6 C-12-7 C-12-8 C-12-9 C-12-10 C-12-11 C-12-12 C-13 C-14 C-14-1 C-14-2 C-14-3 C-14-4 C-14-5 C-14-6 C-14-7 FSDev_SD_Card_BSP_CmdWaitEnd() .............................................. 477 FSDev_SD_Card_BSP_CmdDataRd() ............................................... 481 FSDev_SD_Card_BSP_CmdDataWr() ............................................... 484 FSDev_SD_Card_BSP_GetBlkCntMax() ............................................ 487 FSDev_SD_Card_BSP_GetBusWidthMax() ....................................... 488 FSDev_SD_Card_BSP_SetBusWidth() .............................................. 489 FSDev_SD_Card_BSP_SetClkFreq() ................................................. 491 FSDev_SD_Card_BSP_SetTimeoutData() ......................................... 492 FSDev_SD_Card_BSP_SetTimeoutResp() ........................................ 493 SD/MMC SPI mode BSP .................................................................... 493 SPI BSP .............................................................................................. 494 Open() ................................................................................................. 499 Close() ................................................................................................. 501 Lock() / Unlock() ................................................................................. 502 Rd() ..................................................................................................... 503 Wr() ..................................................................................................... 504 ChipSelEn() /ChipSelDis() .................................................................. 505 SetClkFreq() ........................................................................................ 506 Appendix D D-1 D-2 D-3 D-4 D-5 D-6 D-7 D-8 D-9 D-10 C/FS Types and Structures ............................................................. 507 FS_CFG .............................................................................................. 508 FS_DEV_INFO ..................................................................................... 510 FS_DEV_NAND_CFG .......................................................................... 511 FS_DEV_NOR_CFG ............................................................................ 513 FS_DEV_RAM_CFG ............................................................................ 516 FS_DIR_ENTRY (struct fs_dirent) ...................................................... 517 FS_ENTRY_INFO ................................................................................ 518 FS_FAT_SYS_CFG ............................................................................. 520 FS_PARTITION_ENTRY ..................................................................... 522 FS_VOL_INFO ..................................................................................... 523 Appendix E E-1 E-2 E-3 E-4 E-5 C/FS Configuration .......................................................................... 525 File System Configuration ................................................................. 526 Feature Inclusion Configuration ........................................................ 527 Name Restriction Configuration ........................................................ 530 Debug Configuration .......................................................................... 531 Argument Checking Configuration .................................................... 531 13 E-6 E-7 E-8 E-9 File System Counter Configuration ................................................... 532 Fat Configuration ............................................................................... 532 SD/MMC SPI Configuration ............................................................... 533 Trace Configuration ........................................................................... 534 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 ................................................................................ 535 Files and Directories .......................................................................... 536 Using the Shell Commands ............................................................... 537 Commands ......................................................................................... 540 fs_cat .................................................................................................. 541 fs_cd ................................................................................................... 542 fs_cp ................................................................................................... 544 fs_date ................................................................................................ 545 fs_df .................................................................................................... 546 fs_ls ..................................................................................................... 547 fs_mkdir .............................................................................................. 548 fs_mkfs ............................................................................................... 549 fs_mount ............................................................................................. 550 fs_mv .................................................................................................. 551 fs_od ................................................................................................... 552 fs_pwd ................................................................................................ 553 fs_rm ................................................................................................... 554 fs_rmdir ............................................................................................... 555 fs_touch .............................................................................................. 556 fs_umount ........................................................................................... 557 fs_wc ................................................................................................... 558 Configuration ...................................................................................... 559 Appendix G Bibliography ....................................................................................... 561 Appendix H H-1 H-1-1 H-1-2 H-1-3 H-1-4 C/FS Licensing Policy ...................................................................... 563 C/FS Licensing ................................................................................. 563 C/FS Source Code ........................................................................... 563 C/FS Maintenance Renewal ............................................................ 564 C/FS Source Code Updates ............................................................ 564 C/FS Support ................................................................................... 564 14 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--which still delivering good performance. 1-1 WHAT IS A FILE SYSTEM? A file system is a collection of files and directories; since directories are containers of files, a hierarchical organization results. A PC operating system such as Windows or Linux presents its file systems through a visual interface (e.g, "Windows Explorer"), with a tree-like structure of entries that can be moved, renamed or deleted with menus or actions like "dragging and dropping". Alternatively, a headless system like DOS (or any other command line) integrates utilities to accomplish the same operations. Above, we stated that a system "presents its file systems"--file systems plural--because each drive is a separate file system, a separate collection of files. Each of these is anchored by some unique drive letter (Windows) or mount point (Linux) within the larger context of a "virtual" file system wherein every entry has a unique identifier. (Within the "everything is a file" mentality of Linux, this is taken further, but that is beyond this discussion.) Being separate, each file system may have a different format--one may be FAT, the next NTFS-- and will be located on different physical devices or on separate partitions of the same device. If files are to be read from a volume, file system software is required, with three basic elements. First, a device driver must be able to read and write to the device. Next, a file system driver must be able to parse the device's on-disk structures to read the names, 15 Introduction properties and data of files and to format those structures to modify existing entries and create new ones. Finally, an application-level interface must provide for the exigencies of file and directory access. 1-2 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 and IDE/CF. 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. 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 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 16 Introduction the POSIX functions fwrite(), fread() and fsetpos(). Another API with parallel argument placement and meaningful return error codes is provided as an alternate, with functions like FSFile_Wr(), FSFile_Rd() and FSFile_PosSet(). 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. 1-3 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 17 Introduction 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. 1-4 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. 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. 1-5 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. 18 Introduction $ &)6$3, 5HIHUHQFH 0DQXDO % &)6 (UURU &RGHV & &)6 3RUWLQJ 0DQXDO 3UHIDFH ,QWURGXFWLRQ &)6 $UFKLWHFWXUH 'LUHFWRULHV DQG )LOHV ,'(&) 'ULYHU /RJLFDO 'HYLFHV 'ULYHU ' &)6 7\SHVDQG 6WUXFWXUHV 0DVV6WRUDJH &ODVV 06& 'ULYHU ( &)6 &RQILJXUDWLRQ 0DQXDO 1$1' )ODVK 'ULYHU ) 125 )ODVK 'ULYHU &)6 6KHOO &RPPDQGV 0LVFHOODQHRXV 'HYLFHV DQG 9ROXPHV 326,; $3, )$7)LOH 6\VWHP 'HYLFH 'ULYHUV )LOHV 'LUHFWRULHV 5$0'LVN 'ULYHU 6'00& 'ULYHU * %LEOLRJUDSK\ + /LFHQVLQJ 3ROLF\ Figure 1-1 C/FS Book Layout 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, 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, Miscellaneous. In this chapter, you will learn the nomenclature used in C/FS to access files and folders and the ressources 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. 19 Introduction Chapter 6, 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 7, Files. C/FS complements the POSIX API with its own file access API. This chapter explains this API. Chapter 8, Directories. C/FS complements the POSIX API with its own directory access API. This chapter explains this API. Chapter 9, 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 10, 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. Chapter 11, IDE Devices. The IDE driver supports compact flash (CF) cards and ATA IDE hard drives. Chapter 12, Logical Devices Driver. This feature is not available yet. Chapter 13, Mass Storage Class (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. Chapter 14, NAND Flash. 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 15, NOR Flash. 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. 20 Introduction Chapter 16, RAM Disk. This chapter demonstrates the use of the simplest storage medium, the RAM disk. Chapter 17, SD/MMC Devices. 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. Appendix A, C/FS API Reference Manual. 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. Appendix E, C/FS API Configuration Manual. 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, C/FS 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, Bibliographhy. Appendix H, Licensing Policy. 21 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), file system 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_'. 22 C/FS Architecture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igure 2-1 C/FS architecture. 23 C/FS Architecture 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 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. 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 File system object-specific files: Devices (fs_dev.*) 24 C/FS Architecture 2 3 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) Pool management (fs_pool.*) 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) Miscellaneous data types (fs_type.h) Miscellaneous definitions (fs_def.h) Configuration definitions (fs_cfg_fs.h) 25 C/FS Architecture 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. 2-1-7 CPU LAYER 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 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. 26 C/FS Architecture 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. 27 Chapter 3 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 1-01 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. 28 Directories and Files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igure 3-1 C/FS Architecture 29 Directories and Files F3-1(1) 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(). 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) At Micrim, we like to encapsulate CPU 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. 30 Directories and Files F3-1(9) This is the C/FS system driver for FAT file systems. This code is only available to C/FS licensees. 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> \*.* 31 Directories and Files \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. \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. 32 Directories and Files 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. 33 Directories and Files 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. 34 Directories and Files \*.* 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. 35 Directories and Files 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. 36 Directories and Files 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. 37 Directories and Files \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. 38 Directories and Files \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. 39 Directories and Files 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_bch_4bit_a.asm \ecc_bch_8bit_a.asm \ecc_hamming_a.asm \edc_crc_a.asm \Source \edc_crc.h \edc_crc.c \ecc_hamming.h \ecc_hamming.c \ecc_bch_8bit.h \ecc_bch_8bit.c \ecc_bch_4bit.h \ecc_bch_4bit.c \ecc_bch.h \ecc_bch.c \ecc.h \Micrium This directory contains all software components and projects provided by Micrim. \Software This sub-directory contains all the software components and projects. 40 Directories and Files \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. 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_bch_4bit_a.asm contains the assembly language functions to optimize the calculation speed of 4-bit correction BCH (Bos, Ray-Chaudhuri, Hocquenghem) code. ecc_bch_8bit_a.asm contains the assembly language functions to optimize the calculation speed of 8-bit correction BCH (Bos, Ray-Chaudhuri, Hocquenghem) code. 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. 41 Directories and Files 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 \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.c \fs_err.h \fs_file.c \fs_file.h 42 Directories and Files \fs_partition.c \fs_partition.h \fs_pool.c \fs_pool.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. \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. 43 Directories and Files \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 contain 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.h is the ONLY core header file that should be #included by the application. 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. 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_pool.c/h contains the code for pool management (used internally by C/FS). 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). 44 Directories and Files 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 \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. 45 Directories and Files \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 \IDE \fs_dev_ide.c \fs_dev_ide.h \BSP\Template \fs_dev_ide_bsp.c \MSC \fs_dev_msc.c \fs_dev_msc.h \NAND \fs_dev_nand.c \fs_dev_nand.h \PHY \fs_dev_nand_0512_x08.c \fs_dev_nand_0512_x08.h \fs_dev_nand_0512_x08.c \fs_dev_nand_0512_x08.h \fs_dev_nand_0512_x08.c \fs_dev_nand_0512_x08.h \fs_dev_nand_0512_x08.c \fs_dev_nand_0512_x08.h \Template \fs_dev_nand_template.c 46 Directories and Files \fs_dev_nand_template.h \BSP\Template \fs_dev_nand_bsp.c \BSP\Template (GPIO) \fs_dev_nand_bsp.c \BSP\Template (SPI GPIO) \fs_dev_nand_bsp.c \BSP\Template (SPI) \fs_dev_nand_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 \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 47 Directories and Files \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. \Dev This is where you will find the device driver files for the storage devices you are planning on using. \IDE This directory contains the IDE/CF driver files. 48 Directories and Files fs_dev_ide.* are device driver for IDE devices. These files require a set of BSP functions to be defined in a file named fs_dev_ide_bsp.c to work with a particular hardware setup. For more details on this driver, please refer to Chapter 11, "IDE/CF Driver" on page 124. \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 13, "MSC Driver" on page 134. \NAND This directory contains the NAND driver files. fs_dev_nand.* are the device driver for NAND devices. These files require a set of physical-layer functions (defined in a file name fs_dev_nand_<physical type>.*) as well as BSP functions (to be defined in a file named fs_dev_nand_bsp.c) to work with a particular hardware setup. For more details on this driver, please refer to Chapter 14, "NAND Flash Driver" on page 137. \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 15, "NOR Flash Driver" on page 151. \RAMDisk This directory contains the RAM disk driver files. 49 Directories and Files fs_dev_ramdisk.* constitue the RAM disk driver. For more details on this driver, please refer to Chapter 16, "RAM Disk Driver" on page 170. \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 17, "SD/MMC Drivers" on page 174. 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. \Software This sub-directory contains all the software components and projects. 50 Directories and Files \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: IDE, 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. \uC-FS This is the main C/FS directory. 51 Directories and Files \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 Directories and Files \other \CPU \<manufacturer> \<architecture> \*.* \uC-FS \APP\Template \fs_app.c \fs_app.h \CFG\Template \fs_cfg.h \Dev \IDE \fs_dev_ide.c \fs_dev_ide.h \BSP\Template \fs_dev_ide_bsp.c \MSC \fs_dev_msc.c \fs_dev_msc.h \NAND \fs_dev_nand.c \fs_dev_nand.h \PHY \fs_dev_nand_0512_x08.c \fs_dev_nand_0512_x08.h \fs_dev_nand_0512_x08.c \fs_dev_nand_0512_x08.h \fs_dev_nand_0512_x08.c \fs_dev_nand_0512_x08.h \fs_dev_nand_0512_x08.c \fs_dev_nand_0512_x08.h \Template \fs_dev_nand_template.c \fs_dev_nand_template.h \BSP\<template> \fs_dev_nand_bsp.c \NOR <-Cfg <-Cfg <-Cfg <-Cfg <-Cfg 53 Directories and Files \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 \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 <-Cfg <-Cfg <-Cfg <-Cfg 54 Directories and Files \BSP\Template \fs_dev_sd_spi.bsp.c \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 <-Cfg <-Cfg <-Cfg <-Cfg <-Cfg 55 Directories and Files \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.c \fs_err.h \fs_file.c \fs_file.h \fs_partition.c \fs_partition.h \fs_pool.c \fs_pool.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 56 Directories and Files \cpu_core.c \cpu_core.h \cpu_def.h \Cfg\Template \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_bch_4bit_a.asm \ecc_bch_8bit_a.asm \ecc_hamming_a.asm \edc_crc_a.asm \Source \edc_crc.h \edc_crc.c \ecc_hamming.h \ecc_hamming.c \ecc_bch_8bit.h \ecc_bch_8bit.c <-Cfg <-Cfg <-Cfg 57 Directories and Files \ecc_bch_4bit.h \ecc_bch_4bit.c \ecc_bch.h \ecc_bch.c \ecc.h \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 <-Cfg 58 Chapter 4 Miscellaneous This chapter provides information on various concepts used in C/FS. We decided to include this chapter early in the C/FS manual so that you can start using C/FS as soon as possible. In fact, we assume you know little about C/FS and file systems. Concepts will be introduced as needed. 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 Miscellaneous 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 Miscellaneous 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 : 0 : The name of the device driver A single colon 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 `/': 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) 61 Miscellaneous 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. 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) 62 Miscellaneous 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, "FS_CFG_WORKING_DIR_EN" on page 529). 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. 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 (optionally) and a path name; the maximum full name length may be calculated: 63 Miscellaneous FullNameLenmax = VolNameLenmax + PathNameLenmax Figure 2-3 demonstrates these definitions. full name path name myvolume:\MyDir0\MyDir1\MyDir2\my_very_very_long_file_name.txt parent name file name volume name 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 configuration 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. device name sdcard:0: device driver name 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. 64 Miscellaneous 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 v5.4. 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* 44.1 kB 52.5 kB 66.5 kB 79.4 kB OS port (C/OS-III) 0.2 kB 0.2 kB 2.2 kB 2.4 kB LFN support 6.5 kB 6.7 kB 9.3 kB 9.6 kB Directories 1.6 kB 2.2 kB 2.4 kB 3.3 kB Volume check 2.9 kB 3.2 kB 4.7 kB 5.3 kB Partitions 2.7 kB 3.0 kB 3.7 kB 4.2 kB Table 4-1 ROM Requirements. *Includes code and data for ALL file system components and functions except those itemized in the table. 65 Miscellaneous 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 530). Item RAM (bytes) Core 360 Per device 56 + FS_CFG_MAX_DEV_NAME_LEN Per volume 166 + FS_CFG_MAX_VOL_NAME_LEN Per file 132 Per directory 48 Per buffer 36 + MaxSectorSize Per device driver 20 bytes Working directories (FS_CFG_MAX_PATH_NAME_LEN * 2) * TaskCnt Table 4-2 RAM Characteristics The number of tasks that use relative path names See also section 10-1-1 "Driver Characterization" on page 121 for ROM/RAM characteristics of file system suite drivers. 66 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 Devices and Volumes 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 ivides the final unallocated portion of the device into two parts, so that a volume could be located on each (see section 5-4 "Partitions" on page 72). 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_Close() Remove device from file system. FSDev_GetNbrPartitions() Get number of paritions on a device. FSDev_IO_Ctrl() Perform device I/O control operation. FSDev_Open() Add device to file system. FSDev_PartitionAdd() Add partition to device. 68 Devices and Volumes Function Description 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 IDE/CF 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 Devices and Volumes 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 Devices and Volumes 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 Devices and Volumes 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 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. 72 Devices and Volumes (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 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. 73 Devices and Volumes 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. 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. 74 Devices and Volumes 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 Devices and Volumes 5-5 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 5. 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 6. 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 9, "File Systems: FAT" on page 109. 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 76 Devices and Volumes Function Description Valid for Unmounted Volume? 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 5-6 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 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. The return error code from this function provides important information about the volume state: 77 Devices and Volumes 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-8 "FS_FAT_SYS_CFG" on page 520. 78 Devices and Volumes 5-7 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 Devices and Volumes 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 on volume never updated upon write. FS_VOL_CACHE_MODE_WR_BACK Table 5-3 Cache types File access presents a special case. When a file is opened with a combination of FS_FILE_ACCESS_MODE_WR and FS_FILE_ACCESS_MODE_CACHED the update of the directory sector will be delayed until the file is closed. pfile = FSFile_Open("\file.txt", FS_FILE_ACCESS_MODE_WR | FS_FILE_ACCESS_MODE_CACHED, &err); For files in read or write mode, data from the file will be cached. For files in write mode, the update of the directory sector will be delayed until the file is closed. 5-7-1 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. 80 Devices and Volumes FSVol_CacheAssign ((CPU_CHAR *)"sdcard:0:", (FS_VOL_CACHE_API *) NULL, (void *)&CACHE_BUF[0], (CPU_INT32U ) CACHE_BUF_LEN, (CPU_INT08U ) 25, (CPU_INT08U ) 15, (FS_FLAGS ) FS_VOL_CACHE_MODE_WR_BACK, (FS_ERR *)&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 5-1 Cache L5-1(1) Percent of cache buffer dedicated to management sectors. L5-1(2) Percent of cache buffer dedicated to directory sectors. 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.. 81 Devices and Volumes 5-7-2 OTHER CACHING & 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 7-1-3 "Configuring a File Buffer" on page 101), 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 Chapter 6 POSIX API 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. 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. 83 POSIX API 6-1 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() 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() 84 POSIX API Function POSIX Equivalent Function POSIX Equivalent 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 6-1 POSIX API functions. 6-2 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. 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 535). 85 POSIX API 6-3 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. 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 6-1 File state transitions. 86 POSIX API 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(). 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. 6-3-1 OPENING, READING & 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. 87 POSIX API 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 6-2 fs_fopen() mode strings interpretations. 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, 100, p_file); <-<-<-<-- pointer to buffer size of each item number of items 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 6-1. 88 POSIX API void App_Fnct (void) { FS_FILE fs_size_t unsigned char . . . *p_file; 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); /* Chk for EOF. if (eof != 0) { /* See Note #1. APP_TRACE_INFO(("Reached EOF.\r\n")); } else { err = fs_ferror(p_file); /* Chk for error. if (err != 0) { /* See Note #2. */ APP_TRACE_INFO(("Read error.\r\n")); } } fs_fclose(p_file); /* Close file. } else { APP_TRACE_INFO(("Could not open \"\\file.txt\".\r\n")); } . . . */ */ */ */ } Listing 6-1 Example file read. L6-1(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(). L6-1(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. 89 POSIX API 6-3-2 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 6-2. void App_Fnct (void) { FS_FILE *p_file; fs_fpos_t pos; int err; . . . p_file = fs_fopen("\file.txt", "r"); if (p_file == (FS_FILE *)0) { APP_TRACE_INFO(("Could not open file.")); return; } . . . err = fs_fgetpos(p_file, &pos); if (err != 0) { /* Open file ... */ /* ... read from file. */ /* Save file position ... */ 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 6-2 Example file position set/get. 90 POSIX API 6-3-3 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. 91 POSIX API static CPU_INT32U App_FileBuf[512 / 4]; /* Define file buffer. */ void 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 6-3 Example file buffer usage. L6-3(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. L6-3(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. 92 POSIX API 6-3-4 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. 6-3-5 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 6-4 Example file lock usage. 93 POSIX API L6-4(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. 6-4 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 6-2 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. */ */ */ */ */ */ 94 POSIX API 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 6-5 Directory Listing Output (example) 95 POSIX API Figure 6-2 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-6 "FS_DIR_ENTRY (struct fs_dirent)" on page 517. 6-5 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()). 96 Chapter 7 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 7-1. 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 7-3. 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 7-1 and Table 7-3 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. 97 Files 7-1 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. 98 Files Table 7-1 File Access Functions 7-1-1 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 99 Files It is impossible to do this in a single, atomic operation using fs_fopen(). 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 7-2 fopen() mode strings and mode equivalents 7-1-2 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: 100 Files Attrib contains the file attributes (see section 7-2-1 "File and Directory Attributes" on page 104). Size is the size of the file, in octets. 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. 7-1-3 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 6-3-3 "Configuring a File Buffer" on page 91. 101 Files 7-1-4 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 6-3-4 "Diagnosing a File Error" on page 93. 7-1-5 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 6-3-5 "Atomic File Operations Using File Lock" on page 93. 102 Files 7-2 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 7-3 Entry API Functions 103 Files 7-2-1 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: The second argument should be the logical OR of relevant attribute flags. 104 Files 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. 7-2-2 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. 105 Files Similar functions exist to copy and rename an entry: FSEntry_Copy("\\dir\\src.txt", "\\dir\\dest.txt , <-- source file name <-- destination file name DEF_NO, <-- DEF_NO means creation not exclusive &err); <-- return error FSEntry_Rename ("\\dir\\oldname.txt", <-- old file name "\\dir\\newname.txt", <-- new file name DEF_NO, <-- DEF_NO means creation not exclusive &err); <-- 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. 7-2-3 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. 106 Chapter 8 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 7-2 "Entry Access Functions" on page 103. 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 8-1 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 6, "POSIX API" on page 83. 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. 107 Directories 8-1 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 8-1 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 6-4 "Directory Access Functions" on page 94. 108 Chapter 9 File Systems: FAT The FAT (File Allocation Table) file system, introduced as a simple file system for small disk drives, still predominates the removable storage market, because it is supported by all major operating systems. Since FAT's inception, it has been extended to support larger disks as well as longer file names. However, it remains simple enough for the most resource-constrained embedded system. 109 File Systems: FAT 9-1 FAT ARCHITECTURE A FAT volume consists of four basic areas: 1 Reserved area. The reserved area includes the boot sector, which contains basic format information, like the number of sectors in the volume. 2 FAT. The FAT is a large table with one entry for each cluster. Each entry contains one of three values: the free cluster mark (indicating that it is not allocated), the cluster number of the next entry in the file (essentially, a link in a list of the file's clusters), or the end-of-cluster mark (indicating that it is the final cluster in the file). 3 Root directory. Note that in FAT32 volumes, the root directory is also part of the data area. 4 Data area. The data area contains files and directories, which are just a special type of file. FAT12/16 Rsvd Area 1st FAT Area 2nd FAT Area FAT32 Rsvd Area 1st FAT Area 2nd FAT Area Root Dir Data Area Data Area Figure 9-1 FAT Volume Layout 110 File Systems: FAT 9-1-1 FAT12 / FAT16 / FAT32 The earliest version of FAT, the file system integrated into Microsoft's DOS, was FAT12, so-called because each entry in the File Allocation Table was 12-bits. This limited disk size to approximately 32-MB. Extensions to 16- and 32-bit entries (FAT16 and FAT32) expand support to 2-GB and 8-TB, respectively. As described in Appendix E, "Fat Configuration" on page 532, support for FAT12, FAT16 and FAT32 can be individually disabled, if desired. FAT32 introduces several new innovations above its predecessors. 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 are also included: 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. 9-1-2 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 127 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. Eventually, in a backwards-compatible extension, Microsoft introduced long file names (LFNs). LFNs are limited to 255 characters, stored as 16-bit Unicode in long directory entries. Each name is stored with a short file name composed by attaching a numeric "tail" to the original; this results in names like "file~1.txt". In addition to the characters allowed in SFNs, the following are allowed in LFNs: + , ; = [ ] 111 File Systems: FAT As described in Appendix E, "Fat Configuration" on page 532, 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 527). 9-1-3 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 in Figure 9-2, with the following fields: Name is the 11-character 8.3 SFN. Attr are the attributes of the entry, indicating whether it is a file or directory, writable or read-only and visible or hidden. Creation Time and Creation Date are the time and date when the entry was created. Access Date is the date on which the file was last accessed. Write Time and Write Date are the time and date when the entry was last modified. 1st Cluster High and 1st Cluster Low contain the first cluster containing the file's data. File Size is the file size, in octets. If the entry is a directory, this is blank. 4 8 12 Name Creation Date Access Date Attr st 1 Cluster High 16 NT res Crt ms Creation Time st Write Time Write Date 1 Cluster Low File Size Figure 9-2 FAT Directory Entry (SFN Entry) Within C/FS, these are called Short File Name entries or SFN entries. 112 File Systems: FAT 4 0x42 `.' 0xFFFF 0x01 `o' 0xFFFF `a' 0xFFFF `b' Creation Date `c' 0xFFFF `c' `h' Access Date `e' 0xFFFF `~' `1' `o' `p' 1st Cluster Write Time Write Date High 0xFFFF 0x0F 0x00 0x0000 `k' 16 Chk 0x0F 0x00 sum 0x0000 `e' `j' `f' 0xFFFF `d' `i' `d' 12 0x0000 `p' `b' `g' `a' 8 0xFFFF Chk sum `f' `l' 0x00 0x00 1st Cluster Low 0xFFFF `m' Crt ms Creation Time File Size Figure 9-3 LFN Directory Entry To extend FAT for longer names, Microsoft devised the LFN directory entry, as shown in Figure 9-2. Thirteen characters overlay the fields in a traditional SFN entry, in addition to several important markers. The zeroth byte of the entry gives its order in the LFN entry sequence; the first always has the sixth bit set. If three entries were necessary, they would carry order numbers of 0x43, 0x02 and 0x01, respectively. None of these, you may note, are valid characters (which allows backward compatibility). Byte 11, where the attributes value is in a SFN, is always 0x0F; Microsoft found that no older software would modify or use a directory entry with this marker. Figure 9-3 gives an example of the directory entries created for the file "abcdefghijklm.op". The checksum, stored in byte 13, is calculated from the SFN. It is checked each time the directory entries are parsed; if incorrect, the file system software knows that the SFN was modified (presumably by a system not LFN-aware). 113 File Systems: FAT 4 Ord Char 1 Char 7 8 Char 2 Char 8 Char 3 Char 9 Char 4 Char 10 4 0x42 `.' 0xFFFF 0x01 `a' `a' 0xFFFF Creation Date `c' 0xFFFF `c' `h' `b' Access Date `e' 0xFFFF 0xFFFF `~' `o' `p' 1st Cluster Write Time Write Date High 0xFFFF 0x0F 0x00 0x0000 `k' `1' Char 12 16 Chk 0x0F 0x00 sum 0x0000 `e' `j' `f' Char 12 Char 6 12 `d' `i' `d' 0x0000 Char 11 0x0000 `p' `b' `g' Char 5 16 Chk 0x0F 0x00 sum 8 `o' 0xFFFF 12 0xFFFF Chk sum `f' `l' 0x00 0x00 1st Cluster Low 0xFFFF `m' Crt ms Creation Time File Size Figure 9-4 SNF entry and LFN entries for file named "abcdefghijklm.op" 9-1-4 FAT SYSTEM DRIVER ARCHITECTURE As shown in Figure 9-2, the FAT system driver intermediates between functions that access files and directories (e.g., fs_fopen()) and volume read/write functions. Internally, the FAT system driver is divided into three subsystems, as shown in Figure 9-4. The first consists of the core functions directly called by file, directory, entry and volume modules. Next are the functions that understand the layout of the File Allocation Table and can allocate and free clusters. The final subsystem can create SFN and LFN directory entries and search a directory for a specific entry. 114 File Systems: FAT Files Directories Entries fs_file.* fs_dir.* fs_entry.* fs_fat_file.* fs_fat_file.* fs_fat_entry.* FAT System Driver Directory Entries fs_fat_lfn.* fs_fat_sfn.* FAT Access Core fs_fat.* fs_fat_fat12.* fs_fat_fat16.* fs_fat_fat32.* Volume fs_vol.* Figure 9-5 FAT system driver architecture 9-2 OPERATIONS The application rarely needs to know about the underlying file system; the FAT system driver within C/FS handles file and volume accesses in a transparent manner. A few specific cases, the application may benefit from increased awareness of FAT operation. 9-2-1 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 9-1. 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 520. 115 File Systems: FAT 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 9-1 Example device format 9-2-2 DISK CHECK Errors may accrue on a FAT volume, either by device removal during file system modifications 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). 116 File Systems: FAT 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. 9-2-3 JOURNALING Since cluster allocation information is stored separately from file information and directory entries, most operations, such as adding data to a file, are non-atomic. The repercussions can be innocuous (e.g., wasted disk space) or serious (e.g., directory corruption). C/FS includes an optional journaling add-on to its FAT system driver. System actions--such as creating a new file--are wrapped by updates to a special journal file. The journal is a compendium of logs, descriptions of the system before and after . When an operation is started, an enter log is added to the journal; upon completion, an exit log is added. Logs, for more complex operations, may be nested, the outer log giving additional context to the inner. void App_InitFS (void) { FS_ERR err; . . . /* Init the FS, Open Device and Volume(s) */ FS_FAT_JournalOpen("sd:0:", &err); APP_TEST_FAULT(err, FS_ERR_NONE); . . . } Listing 9-2 Opening the journal 117 File Systems: FAT void App_Task (void *p_arg) { . . . FS_FAT_JournalStart("sd:0:", &err); . . . FS_FAT_JournalStop("sd:0:", &err); . . . /* Start journaling. */ /* Perform fail-safe operations. */ /* Stop */ journaling. /* Perform non-fail-safe operations. */ } Listing 9-3 Starting and stopping journaling 118 Chapter 10 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'). 119 Device Drivers 10-1 PROVIDED DEVICE DRIVERS Portable device drivers are provided for standard media categories: IDE driver. The IDE driver supports compact flash (CF) cards and ATA IDE hard drives. MSC driver. The MSC (Mass Storage Class) driver supports USB host MSC devices (i.e., thumb drives or USB drives) via C/USB-Host. NAND driver. The NAND flash driver support parallel (typically ONFI-compliant) and serial (typically Atmel Dataflash) NAND flash devices. NOR driver. The NOR flash driver support parallel (typically CFI-compliant) and serial (typically SPI) NOR flash devices. 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. Table 10-1 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 IDE/CF "ide:" FSDev_IDE Chapter 11, on page 124 MSC "msc:" FSDev_MSC Chapter 13, on page 134 NAND "nand:" FSDev_NAND Chapter 14, on page 137 NOR "nor:" FSDev_NOR Chapter 15, on page 151 RAM disk "ram:" FSDev_RAM Chapter 16, on page 170 120 Device Drivers Driver Driver Name Driver API Structure Name Reference SD/MMC "sd:" / "sdcard:" FSDev_SD_SPI / FSDev_SD_Card Chapter 17, on page 174 Table 10-1 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 394 describes how to do this. 10-1-1 DRIVER CHARACTERIZATION Typical ROM requirements are summarized in Table 10-2. The ROM data were collected on IAR EWARM v5.50 with high size optimization. Driver ROM, Thumb ROM, ARM Mode Mode IDE/CF * 3.6 kB 5.2 kB MSC** 1.2 kB 1.6 kB NAND*** 8.7 kB 12,1 kB 10.9 kB 15.2 kB RAM disk 0.9 kB 1.2 kB SD/MMC CardMode* 5.9 kB 8.6 kB SD/MMC SPI* 5.5 kB 7.9 kB NOR*** Table 10-2 Driver ROM requirements * Not including BSP **Not including C/USB ***Not including physical-level driver or BSP Typical RAM requirements are summarized in Table 10-3. 121 Device Drivers Driver IDE/CF RAM (Overhead) RAM (Per Device) 8 bytes 24 bytes MSC* 12 bytes 32 bytes NAND 8 bytes --- bytes NOR*** 8 bytes --- bytes RAM disk 8 bytes 24 bytes SD/MMC CardMode 8 bytes 54 bytes SD/MMC SPI 8 bytes 54 bytes Table 10-3 Driver RAM requirements *Not including C/USB ***See section 15-2 "Driver & Device Characteristics" on page 154. Performance can vary significantly as a result of CPU and hardware differences, both as well as file system format. Table 10-4 lists results for three general performance tests: Read file test. Read a file in 4-kB chunks. The time to open the file is NOT included in the time. Write file test. Write a file in 4-kB chunks. The time to open (create) the file is NOT included in the time. 122 Device Drivers Performance (kB/s) Driver CPU Configuration Read file Write file IDE/CF* Freescale iMX27 200-MHz 7930 kB/s 1140 kB/s MSC** NXP LPC2468 48-MHz 309 kB/s 142 kB/s NOR (parallel)*** ST STM32F103VE 72-MHz 1820 kB/s 213 kB/s NOR (serial) ST STM32F103VE 72-MHz 691 kB/s 55 kB/s RAM disk NXP LPC2468 48-MHz 8260 kB/s 4530 kB/s SD/MMC CardMode NXP LPC2468 48-MHz, 1-bit mode 1010 kB/s 387 kB/s SD/MMC CardMode NXP LPC2468 48-MHz, 4-bit mode 2310 kB/s 557 kB/s SD/MMC SPI NXP LPC2468 48-MHz 405 kB/s 212 kB/s SD/MMC SPI NXP LPC2468 48-MHz (w/CRC) 356 kB/s 197 kB/s Table 10-4 Driver performance (file test) *Using 4-GB SanDisk Ultra II CF card **Using 1-GB SanDisk Cruzer Micro ***Using ST M29W128GL NOR Using ST M25P64 serial flash Using 2-GB SanDisk Ultra II SD card 123 Chapter 11 IDE/CF Driver Compact flash (CF) cards are portable, low-cost media often used for storage in consumer devices. Several variants, in different media widths, are widely available, all supported by the IDE driver. ATA IDE hard drives are also supported by this driver. 11-1 FILES AND DIRECTORIES The files inside the IDE driver directory are outlined in this section; the generic file system files, outlined in Chapter 3, "Directories and Files" on page 28, are also required. \Micrium\Software\uC-FS\Dev This directory contains device-specific files. \Micrium\Software\uC-FS\Dev\IDE This directory contains the IDE driver files. fs_dev_ide.* are device driver for IDE devices. This file requires a set of BSP functions be defined in a file named fs_dev_ide_bsp.c to work with a certain hardware setup. .\BSP\Template\fs_dev_ide_bsp.c is a template BSP. See section C-5 "IDE/CF Device BSP" on page 408 for more information. \Micrium\Software\uC-FS\Examples\BSP\Dev\IDE 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_ide_bsp.c 124 IDE/CF Driver 11-2 USING THE IDE/CF DRIVER To use the IDE/CF driver, five files, in addition to the generic file system files, must be included in the build: fs_dev_ide.c (located in the directory specified in Section 9.01). fs_dev_ide.h (located in the directory specified in Section 9.01). fs_dev_ide_bsp.c (located in the user application or BSP). The file fs_dev_ide.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\Drivers\IDE A single IDE/CF volume is opened as shown in Listing 11-1. The file system initialization (FS_Init()) function must have been previously called. ROM/RAM characteristics and performance benchmarks of the IDE driver can be found in section 10-1-1 "Driver Characterization" on page 121. CPU_BOOLEAN { FS_ERR App_FS_AddIDE (void) err; FS_DevDrvAdd((FS_DEV_API *)&FSDev_IDE, /* (1) */ (FS_ERR *)&err); if ((err != FS_ERR_NONE) && (err != FS_ERR_DEV_DRV_ALREADY_ADDED)) { return (DEF_FAIL); } /* (2) */ FSDev_Open((CPU_CHAR *)"ide:0:", /* (a) */ (void *) 0, /* (b) */ (FS_ERR *)&err); 125 IDE/CF Driver switch (err) { case FS_ERR_NONE: break; case FS_ERR_DEV: case FS_ERR_DEV_IO: case FS_ERR_DEV_TIMEOUT: case FS_ERR_DEV_NOT_PRESENT: return (DEF_FAIL); default: return (DEF_FAIL); } FSVol_Open((CPU_CHAR *)"ide:0:", (CPU_CHAR *)"ide:0:", (FS_PARTITION_NBR ) 0, (FS_ERR *)&err); /* (3) /* (a) /* (b) /* (c) */ */ */ */ switch (err) { case FS_ERR_NONE: break; case case case case case FS_ERR_DEV: FS_ERR_DEV_IO: FS_ERR_DEV_TIMEOUT: FS_ERR_DEV_NOT_PRESENT: FS_ERR_PARTITION_NOT_FOUND: return (DEF_FAIL); default: return (DEF_FAIL); /* (4) */ } return (DEF_OK); } Listing 11-1 Opening a IDE/CF device volume L11-1(1) Register the IDE/CF device driver. L11-1(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 ("ide"), a single colon, an ASCII-formatted integer (the unit number) and another colon. Since the IDE/CF driver requires no configuration, the configuration structure (1b) should be passed a NULL pointer. 126 IDE/CF Driver Since IDE/CF 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). L11-1(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. L11-1(4) High level format can be applied to the volume if FS_ERR_PARTITION_NOT_FOUND is returned by the call to FSVol_Open() function. If the IDE 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 534 about configuring the trace level. Figure 11-1 IDE Detection Trace Output. 127 IDE/CF Driver 11-2-1 ATA (TRUE IDE) COMMUNICATION The interface between an ATA device and host is comprised of data bus, address bus and various control signals, as shown in Figure 11-2. Three forms of data transfer are possible, each with several timing modes: 1 PIO (programmed input/output). PIO must always be possible; indeed, it may be the only possible transfer form on certain hardware. Using PIO, data requests are satisfied by direct reads or writes to the DATA register. The IDENTIFY_DEVICE command and standard sector and multiple sector read/write commands always involve this type of transfer. Five timing modes (0, 1, 2, 3 and 4) are standard; two more (5 and 6) are defined in the CF specification. 2 Mutiword DMA. In Multiword DMA mode, a DMARQ and -DMACK handshake initiates automatic data transmission, during which the host moves data between its memory and the bus. The DMA read/write commands (READ_DMA, WRITE_DMA) may use Multiword DMA. Three timing modes (0, 1 and 2) are standard; two more (3 and 4) are defined in the CF specification. 3 Ultra DMA. The purposes of several control signals are reassigned during Ultra DMA transfers. For example, IORDY becomes either DDMARDY or DSTROBE (depending on the direction) to control data flow. The DMA read/write commands (READ_DMA, WRITE_DMA) may use Ultra DMA. Seven timing modes (0, 1, 2, 3, 4, 5 and 6) are standard. MCU/MPU D[0..15] A[0..2] -CS0 -CS1 -IORD -IOWR -IORDY INTRQ -RESET DMARQ -DMACK -DASP -CD1 -CD2 IDE Drive / CF Card D00..D15 A00..A02 -CS0 -CS1 -IORD -IOWR -IORDY INTRQ -RESET DMARQ -DMACK -DASP -CD1 -CD2 -CSEL -ATA_SEL Figure 11-2 True IDE (ATA) host/device connection 128 IDE/CF Driver Pin Name(s) Function A00, A01, A02, -CS0, -CS1 Address group. Use by host to select the register or data port that will be accessed. -IORD Asserted by host to read register or data port. -IOWR Asserted by host to write register or data port. -IORDY INTRQ Interrupt request to the host. -RESET Hardware reset signal. DMARQ Asserted by device when it is ready for a DMA transfer. -DMACK DMA acknowledge signal asserted by host in response to DMARQ. -DASP Disk Active/Slav Present signal in Master/Slave handshake protocol. -CD1, -CD2 Chip detect. The host controls the device via 8 registers (see Figure 11-3). Seven of these registers comprise the command block: FR, SC, SN, CYL, CYH, DH and CMD. The command block registers are written, in sequence, to execute a command. Afterwards, the error and status register return to the host a failure indicator or otherwise signal device operation completion. The need to poll these registers is removed if the host is instead alerted by an interrupt request (on the INTRQ signal) to attend to the device. Up to two devices, known as master and slave (or device 0 and device 1) may be located on a single conventional bus. The active device (the target for the next command) is selected by the DEV bit in the DH register, and generally only one device can be accessed at a time, meaning that a read or write to one cannot interrupt a read or write to the other. 129 IDE/CF Driver SRST Software reset bit nIEN Device interrupt enable DEVCTRL 0 DEV Device selected: 0 = Device 0 (Master) 1 = Device 1 (Slave) DH ERR STATUS Command-depen Obsolete ABRT Command has been aborted Reserved DRDY Device is ready to accept commands DRQ Device is ready to transfer a word of data BSY Device is busy ERR Error occurred during execution of previous command and ALTSTATUS Figure 11-3 Register definitions Control Signals Abbreviation Name R/W CS1 CS0 A02 A01 A00 DATA Data R/W 0 1 0 0 0 ERR Error R 0 1 0 0 1 FR Features W 0 1 0 0 1 SC Sector Count W 0 1 0 1 0 SN Sector Number W 0 1 0 1 1 CYL Cylinder Low W 0 1 1 0 0 CYH Cylinder High W 0 1 1 0 1 DH Card/Drive/Head W 0 1 1 1 0 CMD Command W 0 1 1 1 1 STATUS Status R 0 1 1 1 1 ALTSTATUS Alternate Status R 1 0 1 1 0 DEVCTRL Device Control W 1 0 1 1 0 130 IDE/CF Driver 11-2-2 IDE BSP OVERVIEW A BSP is required so that the IDE driver will work on a particular system. The functions shown in the table below must be implemented. Pleaser refer to section C-5 "IDE/CF Device BSP" on page 408 for the details about implementing your own BSP. Function Description FSDev_IDE_BSP_Open() Open (initialize) hardware. FSDev_IDE_BSP_Close() Close (uninitialize) hardware. FSDev_IDE_BSP_Lock() Acquire IDE bus lock. FSDev_IDE_BSP_Unlock() Release IDE bus lock. FSDev_IDE_BSP_Reset() Hardware-reset IDE device FSDev_IDE_BSP_RegRd() Read from IDE device register. FSDev_IDE_BSP_RegWr() Write to IDE device register. FSDev_IDE_BSP_CmdWr() Write command to IDE device register. FSDev_IDE_BSP_DataRd() Read data from IDE device. FSDev_IDE_BSP_DataWr() Write data to IDE device. FSDev_IDE_BSP_DMA_Start() Setup DMA for command (Initialize channel). FSDev_IDE_BSP_DMA_End() End DMA transfer (and uninitialize channel). FSDev_IDE_BSP_GetDrvNbr() Get IDE drive number. FSDev_IDE_BSP_GetModesSupported() Get supported transfer modes. FSDev_IDE_BSP_SetMode() Set transfer modes. FSDev_IDE_BSP_Dly400_ns() Delay for 400 ns. Table 11-1 IDE BSP Functions 131 IDE/CF Driver Start No DMA Command? Yes Write command FSDev_IDE_BSP_CmdWr() Setup DMA FSDev_IDE_BSP_DMA_Start() Wait for data request Write command FSDev_IDE_BSP_CmdWr() Read or write data FSDev_IDE_BSP_DataRd/Wr() End DMA FSDev_IDE_BSP_DMA_End() More data? Yes No Check for error Return Figure 11-4 Command execution 132 Chapter 12 Logical Device Driver The logical device driver is not released yet. It should be released in a soon future. 133 Chapter 13 MSC Driver The MSC driver supports USB mass storage class devices (i.e., USB drives, thumb drives) using the C/USB host stack. 13-1 FILES AND DIRECTORIES The files inside the MSC driver directory are outlined in this section; the generic file-system files, outlined in Chapter 3, "Directories and Files" on page 28, 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. 134 MSC Driver 13-2 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 13-1. 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 13-1. ROM/RAM characteristics and performance benchmarks of the MSC driver can be found in section 10-1-1 "Driver Characterization" on page 121. 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 13-1 Example C/USB initialization 135 MSC Driver static void App_USB_HostMSC_ClassNotify (void CPU_INT08U void *pclass_dev, is_conn, *pctx) { USBH_MSC_DEV *p_msc_dev; USBH_ERR 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: /* ----- MASS STORAGE DEVICE REMOVED ---- */ FSDev_MSC_DevClose(p_msc_dev); USBH_MSC_RefRel(p_msc_dev); break; default: break; } } Listing 13-2 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 13-1 (if a sufficiently high trace level is configured) when the a MSC device is connected. See section E-9 "Trace Configuration" on page 534 about configuring the trace level. Figure 13-1 MSC Detection Trace Output 136 Chapter 14 NAND Flash Driver 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. Standard storage media (like hard drives) or managed flash-based devices (like 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. The driver for a raw NAND flash (or raw NOR flash, for that matter) is more complicated. Flash is divided into large blocks (often 16-kB to 512-kB); however, the high-level software expects to read or write small sectors (512-bytes to 4096-bytes) atomically. The driver implements a small block abstraction (SBA) to conceal the device geometry from the file system. To aggravate matters, each block may be subjected to a finite number of erases only. A wear-leveling algorithm must be employed so that each block is used equally.. Device Capacity Page Size Block Size Endurance ECC Small-page 128 Mb to 1 512 bytes 16 kB 100,000 1-bit correction, SLC NAND Flash Gb erases/block 2-bit detection Large-Page SLC 1 Gb to 4 Gb 128 kB or 256 100,000 1-bit correction, kB erases/block 2-bit detection Category NAND Flash 2 kB or 4 kB Table 14-1 NAND Flash Devices 137 NAND Flash Driver 14-1 FILES AND DIRECTORIES The files inside the NAND driver directory are outlined in this section; the generic file-system files, outlined in Chapter 3, "Directories and Files" on page 28, are also required. \Micrium\Software\uC-FS\Dev This directory contains device-specific files. \Micrium\Software\uC-FS\Dev\NAND This directory contains the NAND driver files. fs_dev_nand.* These files are device driver for NAND flash devices. This file requires a set of BSP functions be defined in a file named fs_dev_nand_bsp.c to work with a certain hardware setup. .\BSP\Template\fs_dev_nand_bsp.c This is a template BSP for traditional NAND devices accessed via a bus interface. See section C-7 "NAND Flash BSP" on page 440 for more information. .\BSP\Template (GPIO)\fs_dev_nand_bsp.c This is a template BSP for NAND devices accessed via GPIO. See section C-7 "NAND Flash BSP" on page 440 for more information. .\BSP\Template (SPI GPIO)\fs_dev_nand_bsp.c This is a template BSP for Atmel Dataflash devices accessed via GPIO (bit-banging). See section C-8 "NAND Flash SPI BSP" on page 450 for more information. .\BSP\Template (SPI)\fs_dev_nand_bsp.c This is a template BSP for Atmel Dataflash devices accessed via SPI. See section C-8 "NAND Flash SPI BSP" on page 450 for more information. 138 NAND Flash Driver .\PHY This directory contains physical-level drivers for specific NAND types: fs_dev_nand_0512x08.* 512-byte page NAND, 8-bit data bus fs_dev_nand_2048x08.* 2048-byte page NAND, 8-bit data bus fs_dev_nand_2048x16.* 2048-byte page NAND, 16-bit data bus fs_dev_nand_at45.* Atmel AT45 serial flash .\PHY\Template\fs_dev_nand_phy.c This is a template for a physical-layer driver. \Micrium\Software\uC-FS\Examples\BSP\Dev\NAND 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_nand_bsp.c 14-2 DRIVER & DEVICE CHARACTERISTICS All NAND devices 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; only an unprogrammed byte can have its bits changed from 1 to 0. Each block is divided into pages, which comprises a data area 139 NAND Flash Driver (often 512, 2048 or 4096 bytes) and a spare area (often 1/32 the size of the data area). The page is fundamentally the smallest programmable unit, but some devices allow several program operations per page between erases. NAND flash experience occasional bit-errors, where one or more bits stored are flipped upon retrieval. An error-correcting code (ECC) is required so software can correct these bit-errors or take appropriate measures if too many errors occur. A single bit error-correcting code per 512 bytes of data is sufficient for single-level cell (SLC) flash. The driver RAM requirement depends on flash parameters such as block size and run-time configurations such as sector size. Typical cases can be found in the datasheet. 14-3 USING A NAND DEVICE (SOFTWARE ECC) To use the NAND driver, five files, in addition to the generic file system files, must be included in the build: fs_dev_nand.c. fs_dev_nand.h. fs_dev_nand_bsp.c (located in the user application or BSP). A physical-layer driver, typically \Micrium\Software\uC-FS\Dev\NAND\PHY one provided in The file fs_dev_nand.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\NAND \Micrium\Software\uC-FS\Dev\NAND\PHY A single NAND volume is opened as shown in Listing 14-1. The file system initialization (FS_Init()) function must have previously been called and the NAND device driver, FSDev_NAND, registered (using FS_DevDrvAdd()). 140 NAND Flash Driver ROM characteristics and performance benchmarks of the NAND driver can be found in section 10-1-1 "Driver Characterization" on page 121. The NAND driver also provides interface functions to perform low-level operations (see section A-9 "NAND Driver Functions" on page 340). static { CPU_BOOLEAN FS_DEV_NAND_CFG FS_ERR App_FS_AddNAND (void) nand_cfg; err; FS_DevDrvAdd((FS_DEV_API *)&FSDev_NAND, /* (1) */ (FS_ERR *)&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); } nand_cfg.BlkNbrFirst = nand_cfg.BlkCnt = /* (2) APP_CFG_FS_NAND_BLK_NBR_FIRST; APP_CFG_FS_NAND_BLK_CNT; */ nand_cfg.SecSize nand_cfg.RBCnt nand_cfg.PhyPtr = APP_CFG_FS_NAND_SEC_SIZE; = APP_CFG_FS_NAND_RB_CNT; = (FS_DEV_NAND_PHY_API *)APP_CFG_FS_NAND_PHY_PTR; nand_cfg.BusWidth nand_cfg.MaxClkFreq = = APP_CFG_FS_NAND_BUS_WIDTH; APP_CFG_FS_NAND_MAX_CLK_FREQ; 141 NAND Flash Driver FSDev_Open( "nand:0:", (void *)&nand_cfg, &err); switch (err) { case FS_ERR_NONE: APP_TRACE_DBG((" break; /* (3) */ /* (a) */ /* (b) */ ...opened device.\r\n")); case FS_ERR_DEV_INVALID_LOW_FMT: APP_TRACE_DBG((" ...opened device (not low-level formatted).\r\n")); #if (FS_CFG_RD_ONLY_EN == DEF_DISABLED) FSDev_NAND_LowFmt("nand:0:", &err); /* (4) */ #endif if (err != FS_ERR_NONE) { APP_TRACE_DBG((" ...low-level format failed.\r\n")); return (DEF_FAIL); } break; case FS_ERR_DEV: /* Device error. */ 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); } 142 NAND Flash Driver /* (5) FSVol_Open("nand:0:", "nand:0:", 0, &err);*/ switch (err) { case FS_ERR_NONE: APP_TRACE_DBG((" break; /* /* /* */ (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); /* (6) */ #endif if (err != FS_ERR_NONE) { APP_TRACE_DBG((" ...format failed.\r\n")); return (DEF_FAIL); } break; case case case case FS_ERR_DEV: /* Device error. FS_ERR_DEV_IO: FS_ERR_DEV_TIMEOUT: 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 14-1 Opening a NAND device volume L14-1(1) Register the NAND device driver FSDev_NAND. L14-1(2) The NAND device configuration should be assigned. For more information about these parameters, see section D-3 "FS_DEV_NAND_CFG" on page 511. 143 NAND Flash Driver 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 ("nand"), a single colon, an ASCII-formatted integer (the unit number) and another colon. L14-1(4) FSDev_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 associate logical sectors with physical areas of the 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 NAND has just been low-level formatted, there will be no file system on it after it is opened (it will be unformatted) and must be formatted before files can be created or accessed. 144 NAND Flash Driver If the NAND 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 534 about configuring the trace level. Figure 14-1 NAND detection trace output 145 NAND Flash Driver 14-3-1 DRIVER ARCHITECTURE When used with a NAND device, the NAND driver is three layered, as depicted in the figure below. The generic NAND 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 the bus interface and access the NAND. 1$1''ULYHU IVBGHYBQDQGFK 3URYLGHVJHQHULFGULYHULQWHUIDFH HJ LQLWUHDGZULWH DQGSHUIRUPVZHDU OHYHOLQJVRDOOEORFNVDUHXVHGHTXDOO\ 3K\VLFDO/D\HU'ULYHU IVBGHYBQDQGB[ IVBGHYBQDQGB[ IVBGHYBQDQGB[ ,PSOHPHQWVSDUWLFXODU1$1'IODVK FRPPDQGVHW (&& &DOFXODWLRQ &DOFXODWH DQGFKHFN (&& %63 IVBGHYBQDQGBEVSF $FFHVV1$1'YLDEXVLQWHUIDFHRU *3,2 1$1' Figure 14-2 NAND driver architecture 14-3-2 HARDWARE Parallel NAND devices typically connect to a host MCU/MPU via an external bus interface (EBI), with a 8 or 16 data lines, or via GPIO pins. Many silicon vendors offer NAND product lines; many new devices are conformant to the Open NAND Flash Interface (ONFI). A set of query information allows the C/FS NAND driver physical-layer drivers to interface with these newer flash without configuration or modification; most older flash can be handled based purely on device ID. 146 NAND Flash Driver D5RZ 3DJH D %ORFN Q3DJHV D 81 / D D&ROXPQD Pin Input/Output* Description Chip Enable (nCE) O Enables access to a specific chip. Several NANDs can be placed on the same bus if each has a separate chip enable. Command Latch O Indicates that data is a command. Address Latch Enable (ALE) O Indicates that data is an address. Read Enable (nRE) O Enables serial data output from NAND. Write Enable (nWE) O Controls latching of data input to NAND. Read/Busy (R/nB) I Indicates status of NAND operation. Data Bus (D0...D7 I/O Used to write commands and addresses and to read/write Enable (CLE) or D0...D15) data. Table 14-2 Pins, standard NAND *From perspective of CPU 147 NAND Flash Driver 14-3-3 NAND 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-7 "NAND Flash BSP" on page 440 for the details about implementing your own BSP. Function Description FSDev_NAND_BSP_Open() Open (initialize) NAND bus interface. FSDev_NAND_BSP_Close() Close (uninitialize) NAND bus interface. FSDev_NAND_BSP_ChipSelEn() Enable NAND chip select. FSDev_NAND_BSP_ChipSecDis() Disable NAND chip select. FSDev_NAND_BSP_RdData() Read data from NAND. FSDev_NAND_BSP_WrAddr() Write address to NAND. FSDev_NAND_BSP_WrCmd() Write command to NAND. FSDev_NAND_BSP_WrData() Write data to NAND. FSDev_NAND_BSP_WaitWhileBusy() Wait while NAND is busy. Table 14-3 NAND BSP functions The Open()/Close() functions are called upon open/close; these calls are always matched. The remaining functions (RdData(), WrAddr(), WrCmd(), WrData()) read data from or write data to the NAND. 14-4 PHYSICAL-LAYER DRIVERS The physical-layer drivers distributed with the NAND driver (see the table below) support a wide variety of flash devices from major vendors. 148 NAND Flash Driver Driver API Files Description FSDev_NAND_0512x08 fs_dev_nand_0512x08.* Supports 512-byte page SLC flash, 8-bit bus. FSDev_NAND_2048x08 fs_dev_nand_2048x08.* Supports 2048-byte page SLC flash, 8-bit bus. FSDev_NAND_2048x16 fs_dev_nand_2048x16.* Supports 2048-byte page SLC flash, 16-bit bus. FSDev_NAND_AT45 fs_dev_nand_at45.* Supports various Atmel AT45 "DataFlash" serial devices. Figure 14-3 Physical-layer drivers 14-4-1 FSDEV_NAND_0512X08 FSDev_NAND_0512x08 supports small-page (512-byte) SLC NAND flash. The ECC is a 1-bit correct/2-bit detect code; this implementation uses a Hamming code. The sector size cannot exceed the page size, so the configured sector size MUST be 512-bytes. 14-4-2 FSDEV_NAND_2048X08, FSDEV_NAND_2048X16 FSDev_NAND_2048x08 and FSDev_NAND_4096x08 support large-page (2048-byte) SLC NAND flash. The ECC is a 1-bit correct/2-bit detect code; this implementation uses a Hamming code. The sector size cannot exceed the page size, so the configured sector size MUST be less than 2048-bytes. This physical-layer driver advertises its page size as the selected sector size, to take advantage of the partial page programming ability of SLC NAND. If a sector size of 512-bytes is used, the device MUST support at least four partial page programming operations between erases; if a sector size of 1024-bytes is used, the device MUST support at least two partial page programming operations between erases. 149 NAND Flash Driver 14-4-3 FSDEV_NAND_AT45 FSDev_NAND_AT45 supports Atmel's AT45 serial flash memories ("DataFlash"), as described in various datasheets at Atmel (http://www.atmel.com). This driver has been tested with or should work with the devices in the table below. While their underlying flash technology is NOR-type, the AT45-series devices are organized in a typical NAND-like way: each page of the device has a data area and a smaller spare area. No matter which AT45-series device is used, the physical-layer driver advertises its page size as 512-bytes; consequently, the driver MUST be configured with a 512-byte sector size. Device Capacity Device Page Size Device Page Count Atmel AT45DB161D 16 Mb 512-byte 4096 Atmel AT45DB321D 32 Mb 512-byte 8192 Atmel AT45DB641D 64 Mb 1024-byte 8192 Manufacturer Table 14-4 Supported AT45 serial flash 150 Chapter 15 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 15-1 briefly compares these two technologies; specific listings of supported devices are located in section 15-5 "Physical-Layer Drivers" on page 166. 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, SOIC-16, WSON, Atmel SST ST (Numonyx) SPI or multi-bit SPI-like interface. Command sets are generally similar. USON Table 15-1 NOR Flash Devices 151 NOR Flash Driver 15-1 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, "Directories and Files" on page 28, 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 459 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 466 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 466 for more information. 152 NOR Flash Driver .\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 153 NOR Flash Driver 15-2 DRIVER & 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. 154 NOR Flash Driver 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. 155 NOR Flash Driver 15-3 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, typically \Micrium\Software\uC-FS\Dev\NOR\PHY one provided in 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 15-1. 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 10-1-1 "Driver Characterization" on page 121. The NOR driver also provides interface functions to perform low-level operations (see section A-10 "NOR Driver Functions" on page 350). 156 NOR Flash Driver CPU_BOOLEAN App_FS_AddNOR (void) { FS_DEV_NOR_CFG nor_cfg; FS_ERR err; FS_DevDrvAdd((FS_DEV_API *)&FSDev_Nor, /* (1) */ (FS_ERR *)&err); if ((err != FS_ERR_NONE) && (err != FS_ERR_DEV_DRV_ALREADY_ADDED)) { return (DEF_FAIL); } /* (2) */ nor_cfg.AddrBase = APP_CFG_FS_NOR_ADDR_BASE; nor_cfg.RegionNbr = APP_CFG_FS_NOR_REGION_NBR; nor_cfg.AddrStart = APP_CFG_FS_NOR_ADDR_START; nor_cfg.DevSize = APP_CFG_FS_NOR_DEV_SIZE; nor_cfg.SecSize = APP_CFG_FS_NOR_SEC_SIZE; nor_cfg.PctRsvd = APP_CFG_FS_NOR_PCT_RSVD; nor_cfg.PctRsvdSecActive = APP_CFG_FS_NOR_PCT_RSVD_SEC_ACTIVE; nor_cfg.EraseCntDiffTh = APP_CFG_FS_NOR_ERASE_CNT_DIFF_TH; nor_cfg.PhyPtr = (FS_DEV_NOR_PHY_API *)APP_CFG_FS_NOR_PHY_PTR; nor_cfg.BusWidth = APP_CFG_FS_NOR_BUS_WIDTH; nor_cfg.BusWidthMax = APP_CFG_FS_NOR_BUS_WIDTH_MAX; nor_cfg.PhyDevCnt = APP_CFG_FS_NOR_PHY_DEV_CNT; nor_cfg.MaxClkFreq = 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); } 157 NOR Flash Driver *)"nor:0:", /* /* (5) */ (a) */ (CPU_CHAR *)"nor:0:", (FS_PARTITION_NBR ) 0, (FS_ERR *)&err); /* /* (b) */ (c) */ FSVol_Open((CPU_CHAR 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 15-1 Opening a NOR device volume L15-1(1) Register the NOR device driver FSDev_NOR. L15-1(2) The NOR device configuration should be assigned. For more information about these parameters, see section D-4 "FS_DEV_NOR_CFG" on page 513. L15-1(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. L15-1(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. 158 NOR Flash Driver 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 15-1 (if a sufficiently high trace level is configured). See section E-9 "Trace Configuration" on page 534 about configuring the trace level. Figure 15-1 NOR detection trace output 159 NOR Flash Driver 15-3-1 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 15-2 NOR driver architecture (parallel NOR flash) 15-3-2 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: 160 NOR Flash Driver 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 15-2 CFI query information Table 15-2 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 15-5-3 161 NOR Flash Driver "FSDev_NOR_SST39" on page 168 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 15-3 Common command sets 15-3-3 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 459 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 15-4 NOR BSP functions The Open()/Close() functions are called upon open/close; these calls are always matched. 162 NOR Flash Driver 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. 15-4 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 15-3 NOR driver architecture (serial NOR flash) 163 NOR Flash Driver 15-4-1 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 15-5, or similar, are common, and are often employed with the HOLD and WP pins held high (logic low, or inactive), as shown in Table 15-5. 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 15-4 Typical serial NOR connections 164 NOR Flash Driver 15-4-2 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 466. 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 15-5 NOR SPI BSP Functions 165 NOR Flash Driver 15-5 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 15-6 Physical-layer drivers 166 NOR Flash Driver 15-5-1 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. 15-5-2 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 167 NOR Flash Driver 15-5-3 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. 15-5-4 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 15-7 Supported M25 serial flash 168 NOR Flash Driver 15-5-5 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 15-8 Supported SST25 serial flash 169 Chapter 16 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. 16-1 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, "Directories and Files" on page 28, 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. 170 RAM Disk Driver 16-2 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 10-1-1 "Driver Characterization" on page 121. For more information about the FS_DEV_RAM_CFG structure, see section D-5 "FS_DEV_RAM_CFG" on page 516. #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] 171 RAM Disk Driver FSDev_Open((CPU_CHAR *)"ram:0:", (void *)&ram_cfg, (FS_ERR *)&err); if (err != FS_ERR_NONE) { /* (4) */ /* (a) */ /* (b) */ return (DEF_FAIL); } /* (5) FSVol_Open((CPU_CHAR *)"ram:0:", (CPU_CHAR *)"ram: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("ram: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 16-1 Opening a RAM disk volume L16-1(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. L16-1(2) Register the RAM disk driver FSDev_RAM. L16-1(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. 172 RAM Disk Driver L16-1(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. L16-1(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. L16-1(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 16-1 (if a sufficiently high trace level is configured). See section E-9 "Trace Configuration" on page 534 about configuring the trace level. Figure 16-1 RAM Disk Initialization Trace Output 173 Chapter 17 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 17-1, 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. 174 SD/MMC Drivers 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 MMCmobile 18 x 24 x 1.4 mm 13 limited to a single data line. The 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 SDmini 21.5 x 20 x 1.4 mm 11 or in SPI mode. The maximum 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 17-1 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. 175 SD/MMC Drivers 17-1 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, "Directories and Files" on page 28, 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-12 "SD/MMC Cardmode BSP" on page 467 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-13 "SD/MMC SPI mode BSP" on page 493 for more information. .\BSP\Template (GPIO)\fs_dev_sd_spi_bsp.c is a template GPIO (bit-banging) BSP. See section C-13 "SD/MMC SPI mode BSP" on page 493 for more information. 176 SD/MMC Drivers \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 17-2 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 177 SD/MMC Drivers A single SD/MMC volume is opened as shown in Listing 17-1. 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 10-1-1 "Driver Characterization" on page 121. 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-11 "SD/MMC Driver Functions" on page 364). 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) */ */ */ */ 178 SD/MMC Drivers switch (err) { case FS_ERR_NONE: APP_TRACE_DBG((" break; case FS_ERR_DEV: ...opened volume (mounted).\r\n")); 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 17-1 Opening a SD/MMC device volume. L17-1(1) Register the SD/MMC CardMode device driver FSDev_SD_Card. L17-1(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). L17-1(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 179 SD/MMC Drivers 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 17-1 (if a sufficiently high trace level is configured). See section E-9 "Trace Configuration" on page 534 about configuring the trace level. Figure 17-1 SD/MMC detection trace output 17-2-1 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 180 SD/MMC Drivers Pin Name Type Description 5 CLK I Clock 6 VSS2 S Supply voltage ground 7 DAT0 I/O Data Line (Bit 0) 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 17-2 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 17-2 SD/MMC communication sequence F17-2(1) When no data is being transmitted, data lines are held low. F17-2(2) Data block is preceded by a start bit (`0'); an end bit (`1') follows the CRC. F17-2(3) The CRC is the 16-bit CCITT CRC. 181 SD/MMC Drivers F17-2(4) During the busy signaling following a write, DAT0 only is held low. F17-2(5) See Figure 17-3 for description of the command format. F17-2(6) See Figure 17-3 for description of the command format. 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 17-3 SD/MMC command and response formats. F17-3(1) Command index is not valid for response formats R2 and R3. F17-3(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. 17-2-2 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: 182 SD/MMC Drivers 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 17-5 and Figure 17-6. 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(). 183 SD/MMC Drivers 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 17-4 Simplified SD/MMC cardmode initialization and state transitions 184 SD/MMC Drivers Command Response GO_IDLE_STATE No response Fig 15-6 (1) Voltage range Response only for SD V2 cards SEND_IF_COND Reserved 0x00000 20 bits Fig 15-6 (2) 0x1 4 bits Check pattern 0xA5 8 bits Card power May not be 1 on initial up status reading(s) Card Capacity Status SD_SEND_OP_COND 1X Fig 15-6 (3) 1 = High capacity 0 = Standard capacity Reserved 0x00 6 bits VDD Voltage Window 0xFF8000 24 bits OCR 127 MID 63 PRV Example OID PNM PSN MDT ALL_SEND_CID Fig 15-6 (5) CRC MID = Manufacturer ID = 0x03 OID = OEM/Application ID = 0x5344 PNM = Product name = 0x5344303247 = "SD02G" PRV = Product revision = 0x80 = 8.0 PSN = Product serial number = 0x021A7C83 MDT = Manufacturing date = 0x008 0x03534453 0x44303247 0x80021A7C 0x83008B3A Examples SEND_CSD Fig 15-6 (6) (Std capacity)(High capacity) 127 TAAC NSAC CCC TRAN_SPEED C_SIZE 63 CRC 127 TAAC CCC NSAC TRAN_SPEED C_SIZE 63 CRC 0x400E0032 0x5B590000 0x1E5C7F80 0x0A4040DE 0x00260032 0x5F5A83C9 0x3EFBCFFF 0x928040CA Figure 17-5 Command responses (SD card) 185 SD/MMC Drivers 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 17-6 Command responses (MMC card) SD_BUS_WIDTHS Bit 0 = 1-bit Bit 2 = 4-bit 7 3 Figure 17-7 SD SCR Register 186 SD/MMC Drivers DAT_BUS_WIDTH 0x0000 = Regular rd/wr card 00b = 1-bit 01b = 4-bit 511 SD_CARD_TYPE SIZE_OF_PROTECTED_AREA 447 CLASS ERASE_ SIZE 383 SPEED_CLASS 0x00 = Class 0 0x01 = Class 2 0x02 = Class 3 0x03 = Class 4 Figure 17-8 SD Status 17-2-3 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-12 "SD/MMC Cardmode BSP" on page 467 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. 187 SD/MMC Drivers Function Description 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 17-3 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 17-9). 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 17-9 Command execution 188 SD/MMC Drivers 17-3 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 17-2. The file system initialization (FS_Init()) function must have previously been called. 189 SD/MMC Drivers ROM/RAM characteristics and performance benchmarks of the SD/MMC driver can be found in section 10-1-1 "Driver Characterization" on page 121. 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-11 "SD/MMC Driver Functions" on page 364). 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); } 190 SD/MMC Drivers FSDev_Open((CPU_CHAR *)"sd:0:", (void (FS_ERR *) 0, *)&err); /* (2) */ /* (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); } /* (3) */ FSVol_Open((CPU_CHAR *)"sd:0:", /* (a) */ (CPU_CHAR *)"sd:0:", /* (b) */ (FS_PARTITION_NBR ) 0, /* (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 17-2 Opening a SD/MMC device volume L17-2(1) Register the SD/MMC SPI device driver FSDev_SD_SPI. 191 SD/MMC Drivers L17-2(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). L17-2(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 17-10 (if a sufficiently high trace level is configured). See section E-9 "Trace Configuration" on page 534 about configuring the trace level. Figure 17-10 SD/MMC detection trace output 192 SD/MMC Drivers 17-3-1 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 17-4. 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 17-4 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. 193 SD/MMC Drivers 17-3-2 SD/MMC SPI COMMUNICATION DEBUGGING The SD/MMC SPI driver accesses the hardware through a port (SPI BSP) as described in section C-13 "SD/MMC SPI mode BSP" on page 493. 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 17-11 SD/MMC SPI mode communication sequence F17-11(1) When no data is being transmitted, DataOut line is held high. F17-11(2) During busy signaling, DataOut line is held low. F17-11(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. 194 SD/MMC Drivers 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 17-12 SD/MMC SPI mode command and response formats 195 SD/MMC Drivers 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 17-13 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 17-5 and Figure 17-6), 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. 196 SD/MMC Drivers 17-3-3 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-14 "SPI BSP" on page 494. 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 17-5 SD/MMC SPI BSP Functions 197 Appendix A C/FS API Reference Manual 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. 198 C/FS API Reference Manual Section Functions begin with... General file system functions FS_ POXIX API functions fs_ Device functions FSDev_F Directory functions FSDir_ Entry functions FSEntry_ File functions FSFile_ Time functions FSTime_ Volume functions FSVol_ NAND driver functions FSDev_NAND_ NOR driver functions FSDev_NOR_ SD/MMC driver functions FSDev_SD_ Compact Flash/IDE driver functions FSDev_IDE_ MSC driver functions FSDev_MSC_ RAMDisk driver functions FSDev_RAM_ FAT functions FS_FAT_ BSP functions FS_BSP_ OS functions FS_OS_ 199 C/FS API Reference Manual 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 FS_DevDrvAdd() *path_dir, *p_err); void FS_DevDrvAdd (FS_DEV_API *p_dev_drv, FS_ERR *p_err); 200 C/FS API Reference Manual 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 Device driver added. Argument p_dev_drv passed a NULL pointer. FS_ERR_DEV_DRV_ALREADY_ADDED Device driver already added. FS_ERR_DEV_DRV_INVALID_NAME Device driver name invalid. FS_ERR_DEV_DRV_NO_TBL_POS_AVAIL No device driver table position available. RETURNED VALUE None. 201 C/FS API Reference Manual NOTES/WARNINGS 1 2 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). 202 C/FS API Reference Manual 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. 203 C/FS API Reference Manual 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. 204 C/FS API Reference Manual 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. 205 C/FS API Reference Manual 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_NULL_PTR Working directory set. Argument path_dir passed a NULL pointer. FS_ERR_VOL_NONE_EXIST No volumes exist. FS_ERR_WORKING_DIR_NONE_AVAIL No working directories available. FS_ERR_WORKING_DIR_INVALID Argument path_dir passed an invalid directory. RETURNED VALUE, None. NOTES/WARNINGS None. 206 C/FS API Reference Manual 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 207 C/FS API Reference Manual 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 *p_ts, *p_time); 208 C/FS API Reference Manual 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); 209 C/FS API Reference Manual 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. 210 C/FS API Reference Manual 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... (a) the absolute working directory path to set; (b) relative path that will be applied to the current working directory. RETURNED VALUE 0, if no error occurs. -1, otherwise NOTES/WARNINGS None. 211 C/FS API Reference Manual 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. 212 C/FS API Reference Manual 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. 213 C/FS API Reference Manual 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. 214 C/FS API Reference Manual 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 1 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. 2 If the most recent operation is output (write), all unwritten data is written to the file. 3 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. 215 C/FS API Reference Manual 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 1 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 } 2 If the end-of-file indicator is set (i.e., fs_feof() returns DEF_YES), fs_clearerr() can be used to clear that indicator. 216 C/FS API Reference Manual 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 1 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 } 2 If the error indicator is set (i.e., fs_ferror() returns a non-zero value), fs_clearerr() can be used to clear that indicator. 217 C/FS API Reference Manual 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 1 If the most recent operation is output (write), all unwritten data is written to the file. 2 If the most recent operation is input (read), all buffered data is cleared. 218 C/FS API Reference Manual 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 1 The return value should be tested against 0: rtn = fs_fgetpos(p_file, &pos); if (rtn == 0) { // No error occurred } else { // Handle error } 2 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. 219 C/FS API Reference Manual 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: 1 The file is unlocked when the lock count is zero. 2 If the lock count is positive, a task owns the file. 3 When fs_flockfile() is called, if... a....the lock count is zero OR b....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. 4 Each call to fs_funlockfile() incremenets the lock count. 5 Matching calls to fs_flockfile() (or fs_ftrylockfile()) and fs_funlockfile() can be nested. 220 C/FS API Reference Manual 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 1 The access mode should be one of the strings shown in section Table 7-2 "fopen() mode strings and mode equivalents" on page 100. 2 The character `b' has no effect. 3 Opening a file with read mode fails if the file does not exist. 4 Opening a file with append mode causes all writes to be forced to the end-of-file. 221 C/FS API Reference Manual 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 1 The size or nitems is 0, then the file is unchanged and zero is returned. 2 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. 3 The file must have been opened in read or update (read/write) mode. 222 C/FS API Reference Manual 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. 223 C/FS API Reference Manual NOTES/WARNINGS 1 If a read or write error occurs, the error indicator shall be set. 2 The new file position, measured in bytes form the beginning of the file, is obtained by adding offset to...: a....0 (the beginning of the file), if whence is FS_SEEK_SET; b....the current file position, if whence is FS_SEEK_CUR; c....the file size, if whence is FS_SEEK_END; 3 The end-of-file indicator is cleared. 4 If the file position indicator is set beyond the file's current data... a....and data is later written to that point, reads from the gap will read 0. b....the file MUST be opened in write or read/write mode. 224 C/FS API Reference Manual 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 1 The return value should be tested against 0: rtn = fs_fsetpos(pfile, &pos); if (rtn == 0) { // No error occurred } else { // Handle error } 2 If a read or write error occurs, the error indicator shall be set. 3 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(). 4 See also fs_fseek(). 225 C/FS API Reference Manual 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. 226 C/FS API Reference Manual 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 1 The file MUST be opened in write or read/write mode. 2 If fs_ftruncate() succeeds, the size of the file shall be equal to length. a. If the size of the file was previously greater than length, the extra data shall no longer be available. b. If the file previously was smaller than this length, the size of the file shall be increased. 3 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. 227 C/FS API Reference Manual 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(). 228 C/FS API Reference Manual 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(). 229 C/FS API Reference Manual 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 1 The size or nitems is 0, then the file is unchanged and zero is returned. 2 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. 3 The file must have been opened in write or update (read/write) mode. 4 If the file was opened in append mode, all writes are forced to the end-of-file. 230 C/FS API Reference Manual 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. 231 C/FS API Reference Manual A-2-22 fs_localtime_r() struct fs_tm *fs_localtime_r (const fs_time_t *p_ts, struct fs_tm *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. 232 C/FS API Reference Manual 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"); if (err != 0) { APP_TRACE_INFO(("Could not make dir.")); } /* Make dir. */ . . . } 233 C/FS API Reference Manual 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. 234 C/FS API Reference Manual 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. 235 C/FS API Reference Manual 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 Pointer to variable that will receive directory entry information. pp_result Pointer to variable that will receive: (a) p_dir_entry, if NO error occurs AND directory does not encounter EOF. (b) pointer to NULL if an error occurs OR directory encounters EOF. RETURNED VALUE 1, if an error occurs. 0, otherwise. NOTES/WARNINGS 1 Entries for "dot" (current directory) and "dot-dot" (parent directory) shall be returned, if present. No entry with an empty name shall be returned. 2 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. 236 C/FS API Reference Manual 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 1 When a file is removed, the space occupied by the file is freed and shall no longer be accessible. 2 A directory can be removed only if it is an empty directory. 3 The root directory cannot be removed. 237 C/FS API Reference Manual 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.")); } . . . */ */ } 238 C/FS API Reference Manual 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 1 name_full_old and name_full_new MUST specify entries on the same volume. 2 If path_old and path_new specify the same entry, the volume will not be modified and no error will be returned. 3 If path_old specifies a file: a. path_new must NOT specify a directory; b. if path_new is a file, it will be removed. 239 C/FS API Reference Manual If path_old specifies a directory: 4 a. path_new must NOT specify a file b. if path_new is a directory, path_new MUST be empty; if so, it will be removed. 5 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: 1 The file sd:0:\data\file001.txt must exist. 2 The directory sd:0:\data\old must exist. 3 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. 240 C/FS API Reference Manual 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 1 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. 241 C/FS API Reference Manual 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 1 A directory can be removed only if it is an empty directory. 2 The root directory cannot be removed. 242 C/FS API Reference Manual 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.")); } */ . . . } 243 C/FS API Reference Manual A-2-31 fs_setbuf() int fs_setbuf (FS_FILE *p_file, 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. size Size of buffer, in octets. RETURNED VALUE -1, if an error occurs. 0, if no error occurs. NOTES/WARNINGS 1 fs_setbuf() is equivalent to fs_setvbuf() invoked with FS__IOFBF for mode and FS_BUFSIZE for size. 244 C/FS API Reference Manual 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 Unbuffered. FS__IOFBF Fully buffered. size Size of buffer, in octets. RETURNED VALUE -1, if an error occurs. 0, if no error occurs. 245 C/FS API Reference Manual NOTES/WARNINGS 1 fs_setvbuf() MUST be used after a stream is opened but before any other operation is performed on stream. 2 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. 3 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. 4 Upon power loss, any data stored in file buffers will be lost. 246 C/FS API Reference Manual A-3 DEVICE FUNCTIONS Most device access functions can return any of the following device errors: FS_ERR_DEV_INVALID_LOW_FMT Device needs to be low-level formatted. FS_ERR_DEV Device access error. 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 error. Each of these indicates that the state of the device is not suitable for the intended operation. void FSDev_Close (CPU_CHAR FS_ERR *name_dev, *p_err); FS_PARTITION_NBR FSDev_GetNbrPartitions (CPU_CHAR FS_ERR *name_dev, *p_err); void FSDev_GetDevName (FS_QTY CPU_CHAR FS_QTY FSDev_GetDevCnt (void); FS_QTY FSDev_GetDevCntMax (void); void FSDev_Open (CPU_CHAR void FS_ERR dev_nbr, *name_dev); *name_dev, *p_dev_cfg, *p_err); 247 C/FS API Reference Manual FS_PARTITION_NBR FSDev_PartitionAdd void FSDev_PartitionFind void FSDev_PartitionInit void FSDev_Query void FSDev_Rd CPU_BOOLEAN FSDev_Refresh void FSDev_Wr (CPU_CHAR FS_SEC_QTY FS_ERR *name_dev, partition_size, *p_err); (CPU_CHAR *name_dev, FS_PARTITION_NBR partition_nbr, FS_PARTITION_ENTRY *p_partition_entry, FS_ERR *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); (CPU_CHAR void FS_SEC_NBR FS_SEC_QTY FS_ERR *name_dev, *p_src, start, cnt, *p_err); 248 C/FS API Reference Manual A-3-1 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. 249 C/FS API Reference Manual A-3-2 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. FSDev_GetNbrDevs() (inclusive). n should be between 0 and the return value of ARGUMENTS dev_nbr Device number. name_dev String buffer that will receive the device name (see Note #2). RETURNED VALUE None. NOTES/WARNINGS 1 name_dev MUST point to a character array of FS_CFG_MAX_DEV_NAME_LEN characters. 2 If the device does not exist, name_dev will receive an empty string. 250 C/FS API Reference Manual A-3-3 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. 251 C/FS API Reference Manual A-3-4 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. 252 C/FS API Reference Manual A-3-5 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 377). 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. 253 C/FS API Reference Manual A-3-6 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 254 C/FS API Reference Manual RETURNED VALUE None. NOTES/WARNINGS 1 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. a. If FS_ERR_NONE is returned, then the device has been added to the file system and is immediately accessible. b. 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. c. 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. d. If FS_ERR_DEV_INVALID_NAME, FS_ERR_DEV_INVALID_SEC_SIZE, FS_ERR_DEV_INVALID_SIZE, FS_ERR_DEV_INVALID_UNIT_NBR or FS_ERR_DEV_NONE_AVAIL is returned, then the device has NOT been added to the file system. e. 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. 255 C/FS API Reference Manual A-3-7 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 5-4 "Partitions" on page 72. ARGUMENTS name_dev Device name partition_size Size, in sectors, of the partition to add. p_err 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 377). 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. 256 C/FS API Reference Manual A-3-8 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 5-4 "Partitions" on page 72. 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 377). 257 C/FS API Reference Manual RETURNED VALUE None. NOTES/WARNINGS Device state change will result from device I/O, not present or timeout error. 258 C/FS API Reference Manual A-3-9 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 5-4 "Partitions" on page 72. 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 377). RETURNED VALUE None. 259 C/FS API Reference Manual 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. 260 C/FS API Reference Manual A-3-10 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 377). RETURNED VALUE None. NOTES/WARNINGS None. 261 C/FS API Reference Manual A-3-11 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). 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 377). RETURNED VALUE None. 262 C/FS API Reference Manual NOTES/WARNINGS Device state change will result from device I/O, not present or timeout error. 263 C/FS API Reference Manual A-3-12 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 377). RETURNED VALUE DEF_YES, if the device has not changed. DEF_NO, if the device has not changed. 264 C/FS API Reference Manual NOTES/WARNINGS 1 If device has changed, all volumes open on the device must be refreshed and all files closed and reopened. 2 A device status change may be caused by a. A device was connected, but no longer is. b. A device was not connected, but now is. c. A different device is connected. 265 C/FS API Reference Manual A-3-13 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). 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 377). RETURNED VALUE None. 266 C/FS API Reference Manual NOTES/WARNINGS Device state change will result from device I/O, not present or timeout error. 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 (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); 267 C/FS API Reference Manual 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. 268 C/FS API Reference Manual 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_NULL_PTR 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 378). RETURNED VALUE DEF_NO, if dir is NOT open. DEF_YES, if dir is open. NOTES/WARNINGS None. 269 C/FS API Reference Manual 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_NULL_PTR 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 378). RETURNED VALUE Pointer to a directory, if NO errors. Pointer to NULL, otherwise. 270 C/FS API Reference Manual NOTES/WARNINGS None. 271 C/FS API Reference Manual 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 Pointer to variable that will receive directory entry information. 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 FS_ERR_EOF FS_ERR_DEV FS_ERR_BUF_NONE_AVAIL 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. RETURNED VALUE None. NOTES/WARNINGS None. 272 C/FS API Reference Manual 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); 273 C/FS API Reference Manual 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_NULL_PTR 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 378). RETURNED VALUE None. 274 C/FS API Reference Manual NOTES/WARNINGS 1 If the entry does not exist, an error is returned. 2 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. 3 The attributes of the root directory may NOT be set. 275 C/FS API Reference Manual 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 (see Note #1): 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_NULL_PTR 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. 276 C/FS API Reference Manual Or entry error (See section B-8 "Entry Error Codes" on page 378). RETURNED VALUE None. NOTES/WARNINGS 1 name_full_src must be an existing file. It may not be an existing directory. 2 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. 277 C/FS API Reference Manual 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, FS_ENTRY_TYPE_FILE, excl if the entry shall be a directory. if the entry shall be a file. Indicates whether the creation of the new entry shall be exclusive (see Note #1): 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. p_err Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR FS_ERR_NAME_INVALID Entry created successfully. Argument name_full passed a NULL pointer. Entry name specified invalid OR volume could not be found. 278 C/FS API Reference Manual FS_ERR_NAME_PATH_TOO_LONG FS_ERR_VOL_NOT_OPEN FS_ERR_VOL_NOT_MOUNTED FS_ERR_BUF_NONE_AVAIL FS_ERR_DEV Or entry error. Entry name specified too long. Volume was not open. Volume was not mounted. Buffer not available. Device access error. RETURNED VALUE None. NOTES/WARNINGS 1 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. 2 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. 3 The root directory may not be created. 279 C/FS API Reference Manual 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 if the entry must be a dir. if the entry must be a file. if the entry may be any type. Pointer to variable that will the receive return error code from this function: FS_ERR_NONE FS_ERR_NULL_PTR 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 Or entry error. 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. 280 C/FS API Reference Manual RETURNED VALUE None. NOTES/WARNINGS 1 When a file is removed, the space occupied by the file is freed and shall no longer be accessible. 2 A directory can be removed only if it is an empty directory. 3 The root directory cannot be deleted. 281 C/FS API Reference Manual 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_NULL_PTR 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 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. RETURNED VALUE None. 282 C/FS API Reference Manual NOTES/WARNINGS None. 283 C/FS API Reference Manual 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_NULL_PTR 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. 284 C/FS API Reference Manual FS_ERR_BUF_NONE_AVAIL FS_ERR_DEV FS_ERR_NAME_INVALID Or entry error. Buffer not available. Device access error. Invalid file name or path. RETURNED VALUE None. NOTES/WARNINGS 1 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. 2 If name_full_old and name_full_new specify the same entry, the volume will not be modified and no error will be returned. 3 If name_full_old specifies a file: a. name_full_new must NOT specify a directory; b. if excl is DEF_NO and name_full_new is a file, it will be removed. 4 If name_full_old specifies a directory: a. name_full_new must NOT specify a file b. if excl is DEF_NO and name_full_new is a directory, name_full_new MUST be empty; if so, it will be removed. 5 If excl is DEF_NO, name_full_new must not exist. 6 The root directory may NOT be renamed. 285 C/FS API Reference Manual 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_NULL_PTR Entry date/time set successfully. Argument name_full or p_time passed a NULL pointer. FS_ERR_FILE_INVALID_DATE_TIME Date/time specified invalid. FS_ERR_NAME_INVALID Entry name specified invalid OR volume could not be found. FS_ERR_NAME_PATH_TOO_LONG Entry name specified too long. FS_ERR_VOL_NOT_OPEN Volume was not open. FS_ERR_VOL_NOT_MOUNTED Volume was not mounted. FS_ERR_BUF_NONE_AVAIL Buffer not available. 286 C/FS API Reference Manual FS_ERR_DEV Device access error. RETURNED VALUE None. NOTES/WARNINGS None. 287 C/FS API Reference Manual 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); 288 C/FS API Reference Manual 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 (FS_FILE void CPU_SIZE_T FS_ERR *p_file, size, *p_err); *p_file, *p_src, size, *p_err); 289 C/FS API Reference Manual 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 Data buffered for reads. Data buffered for writes. Data buffered for reads and writes.. size Size of buffer, in octets. 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_INVALID_BUF_MODE File buffer assigned. Argument p_file or p_buf passed a NULL pointer. Argument p_file's type is invalid or unknown. Invalid buffer mode. 290 C/FS API Reference Manual 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. 291 C/FS API Reference Manual 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. 292 C/FS API Reference Manual 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 File closed. 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. 293 C/FS API Reference Manual 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. 294 C/FS API Reference Manual 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. 295 C/FS API Reference Manual 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. 296 C/FS API Reference Manual 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 7-1-1 "Opening Files" on page 99 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 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. RETURNED VALUE DEF_NO if file is NOT open DEF_YES if file is open. 297 C/FS API Reference Manual NOTES/WARNINGS None. 298 C/FS API Reference Manual 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. 299 C/FS API Reference Manual 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 File lock acquired. 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. 300 C/FS API Reference Manual 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. 301 C/FS API Reference Manual 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_NULL_PTR File opened. Argument p_name_full passed a NULL pointer. Or entry error (see Section B.04). RETURNED VALUE None. 302 C/FS API Reference Manual NOTES/WARNINGS 1 The access mode should be the logical OR of one or more 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. 2 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. 303 C/FS API Reference Manual 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. 304 C/FS API Reference Manual 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. 305 C/FS API Reference Manual 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. 306 C/FS API Reference Manual RETURNED VALUE None. NOTES/WARNINGS None. 307 C/FS API Reference Manual 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. 308 C/FS API Reference Manual 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 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. 309 C/FS API Reference Manual RETURNED VALUE The number of bytes read, if file read successful. 0, otherwise. NOTES/WARNINGS None. 310 C/FS API Reference Manual 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 File truncated 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. 311 C/FS API Reference Manual 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. 312 C/FS API Reference Manual RETURNED VALUE The number of bytes written, if file write successful. 0, otherwise. NOTES/WARNINGS None. 313 C/FS API Reference Manual 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); 314 C/FS API Reference Manual void FSVol_Query void FSVol_Rd void FSVol_Wr (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); 315 C/FS API Reference Manual 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. 316 C/FS API Reference Manual 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 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. REQUIRED CONFIGURATION None. 317 C/FS API Reference Manual NOTES/WARNINGS 1 Function blocked if files or directories are open on the volume. All files and directories MUST be closed prior to formatting the volume. 2 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. 318 C/FS API Reference Manual 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 1 name_vol MUST point to a character array of FS_CFG_MAX_VOL_NAME_LEN characters. 2 If the volume does not exist, name_vol will receive an empty string. 319 C/FS API Reference Manual 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. 320 C/FS API Reference Manual 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. 321 C/FS API Reference Manual 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. FSVol_GetNbrVols() (inclusive). n should be between 0 and the return value of ARGUMENTS vol_nbr Volume number. name_vol String buffer that will receive the volume name (see Note #2). RETURNED VALUE None. NOTES/WARNINGS 1 name_vol MUST point to a character array of FS_CFG_MAX_VOL_NAME_LEN characters. 2 If the volume does not exist, name_vol will receive an empty string. 322 C/FS API Reference Manual 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. 323 C/FS API Reference Manual 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. 324 C/FS API Reference Manual 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 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. 325 C/FS API Reference Manual 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.. 326 C/FS API Reference Manual 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 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. 327 C/FS API Reference Manual 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. 328 C/FS API Reference Manual 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 377). 329 C/FS API Reference Manual RETURNED VALUE None. NOTES/WARNINGS 1 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 a. FSVol_Fmt(), which creates a file system on the device; b. FSVol_Close(), which frees the volume structure; c. FSVol_Query(), which returns information about the device. 2 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. 330 C/FS API Reference Manual 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 Volume information obtained. Device access error. Argument name_vol passed a NULL pointer. Argument p_info passed a NULL pointer. Volume is not open. RETURNED VALUE None. NOTES/WARNINGS None. 331 C/FS API Reference Manual 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. 332 C/FS API Reference Manual RETURNED VALUE None. REQUIRED CONFIGURATION None. NOTES/WARNINGS None. 333 C/FS API Reference Manual 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. 334 C/FS API Reference Manual 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 (CPU_CHAR *name_vol, FS_ERR *p_err); 335 C/FS API Reference Manual 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 336 C/FS API Reference Manual 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 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. RETURNED VALUE None. NOTES/WARNINGS None. 337 C/FS API Reference Manual 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. 338 C/FS API Reference Manual 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 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. RETURNED VALUE None. NOTES/WARNINGS None. 339 C/FS API Reference Manual A-9 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 void FSDev_NAND_PhyRdSec void FSDev_NAND_PhyWrSec (CPU_CHAR void void FS_SEC_NBR FS_ERR *name_dev, *p_dest, *p_spare sec_nbr_phy, *p_err); (CPU_CHAR void void FS_SEC_NBR FS_ERR *name_dev, *p_src, *p_spare, sec_nbr_phy, *p_err); void FSDev_NAND_PhyEraseBlk (CPU_CHAR *name_dev, CPU_INT32U blk_nbr_phy, FS_ERR *p_err); 340 C/FS API Reference Manual A-9-1 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 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 NAND device (e.g., "nand:0:"). Low-level formating associates physical areas (sectors) of the device with logical sector numbers. 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. 341 C/FS API Reference Manual A-9-2 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 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 NAND device (e.g., "nand: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. 342 C/FS API Reference Manual A-9-3 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. 343 C/FS API Reference Manual A-9-4 FSDev_NAND_PhyRdSec() void FSDev_NAND_PhyRdSec (CPU_CHAR void void FS_SEC_NBR FS_ERR *name_dev, *p_dest, *p_spare, sec_nbr_phy, *p_err); File Called from Code enabled by fs_dev_nand.c Application N/A Read sector from a NAND device and store data in buffer. ARGUMENTS name_dev Device name (see Note). p_dest Pointer to destination buffer. p_spare Pointer to buffer that will receive spare data. sec_nbr_phy p_err Sector to read. 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_DEV_INVALID FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT 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 I/O error. Device timeout. 344 C/FS API Reference Manual RETURNED VALUE None. NOTES/WARNINGS The device MUST be a NAND device (e.g., "nand:0:"). 345 C/FS API Reference Manual A-9-5 FSDev_NAND_PhyWrSec() void FSDev_NAND_PhyWrSec (CPU_CHAR void void FS_SEC_NBR FS_ERR *name_dev, *p_src, *p_spare sec_nbr_phy, *p_err); File Called from Code enabled by fs_dev_nand.c Application N/A Write to a NAND device from a buffer. ARGUMENTS name_dev Device name (see Note). p_src Pointer to source buffer. p_spare Pointer to buffer that contains the spare data. sec_nbr_phy p_err Sector to write. 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 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 I/O error. Device timeout. 346 C/FS API Reference Manual RETURNED VALUE None. NOTES/WARNINGS The device MUST be a NAND device (e.g., "nand: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 page modified is NOT verified 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 page being programmed have not already been programmed. 347 C/FS API Reference Manual A-9-6 FSDev_NAND_PhyEraseBlk() void FSDev_NAND_PhyEraseBlk (CPU_CHAR *name_dev, CPU_INT32U blk_nbr_phy, FS_ERR *p_err); File Called from Code enabled by fs_dev_nand.c Application N/A Erase block of NAND device. ARGUMENTS name_dev Device name (see Note). blk_nbr_phy p_err Block to erase. 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 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 I/O error. Device timeout. RETURNED VALUE None. NOTES/WARNINGS The device MUST be a NAND device (e.g., "nand:0:"). 348 C/FS API Reference Manual 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 verified as being outside any existing file system or low-level format information. 349 C/FS API Reference Manual A-10 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); 350 C/FS API Reference Manual void FSDev_NOR_PhyEraseChip (CPU_CHAR FS_ERR *name_dev, *p_err); 351 C/FS API Reference Manual A-10-1 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. 352 C/FS API Reference Manual A-10-2 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. 353 C/FS API Reference Manual A-10-3 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. 354 C/FS API Reference Manual A-10-4 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. 355 C/FS API Reference Manual A-10-5 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. 356 C/FS API Reference Manual A-10-6 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. 357 C/FS API Reference Manual RETURNED VALUE None. NOTES/WARNINGS The device MUST be a NOR device (e.g., "nor:0:"). 358 C/FS API Reference Manual A-10-7 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. 359 C/FS API Reference Manual 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. 360 C/FS API Reference Manual A-10-8 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. RETURNED VALUE None. 361 C/FS API Reference Manual 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. 362 C/FS API Reference Manual A-10-9 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. 363 C/FS API Reference Manual A-11 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); 364 C/FS API Reference Manual A-11-1 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 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. 365 C/FS API Reference Manual 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:"). 366 C/FS API Reference Manual A-11-2 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 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. RETURNED VALUE None. 367 C/FS API Reference Manual NOTES/WARNINGS 1 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:"). 2 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. 368 C/FS API Reference Manual A-11-3 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 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. RETURNED VALUE None. 369 C/FS API Reference Manual NOTES/WARNINGS 1 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:"). 2 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. 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 (CPU_CHAR *name_vol, FS_ERR *p_err); 370 C/FS API Reference Manual 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. 371 C/FS API Reference Manual 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 Journal closed. Device access error. RETURNED VALUE None. NOTES/WARNINGS None. 372 C/FS API Reference Manual 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. 373 C/FS API Reference Manual 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 Journaling stopped. Device access error. RETURNED VALUE None. NOTES/WARNINGS None. 374 C/FS API Reference Manual 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 pointer. Device access error. Volume not open. No buffers available. null RETURNED VALUE None. NOTES/WARNINGS None. 375 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 No error. 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 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. FS_ERR_WORKING_DIR_NONE_AVAIL FS_ERR_WORKING_DIR_INVALID No working dir avail. Working dir invalid. B-2 BUFFER ERROR CODES FS_ERR_BUF_NONE_AVAIL No buffer available. 376 C/FS Error Codes 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 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. 377 C/FS Error Codes B-5 DEVICE DRIVER ERROR CODES FS_ERR_DEV_DRV_ALREADY_ADDED FS_ERR_DEV_DRV_INVALID_NAME FS_ERR_DEV_DRV_NO_TBL_POS_AVAIL Device driver already added. Invalid device driver name. No pos available in device driver table. 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 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 Paths specify same file system entry. 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. 378 C/FS Error Codes FS_ERR_ENTRY_OPEN Operation not allowed on corresponding to an open file/dir. entry 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 FS_ERR_FILE_NONE_AVAIL FS_ERR_FILE_NOT_OPEN FS_ERR_FILE_NOT_LOCKED FS_ERR_FILE_OVF FS_ERR_FILE_OVF_OFFSET 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. 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 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. 379 C/FS Error Codes FS_ERR_NAME_BUF_TOO_SHORT FS_ERR_NAME_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 FS_ERR_POOL_INVALID_BLK_IX FS_ERR_POOL_INVALID_BLK_NBR FS_ERR_POOL_INVALID_BLK_SIZE Pool is empty. Pool is full. Block not found in used pool pointers. Block found in free pool pointers. 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 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. 380 C/FS Error Codes FS_ERR_SYS_SFN_NOT_AVAIL FS_ERR_SYS_LFN_ORPHANED 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 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. 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 FS_ERR_VOL_DIRS_OPEN No vol avail. No vols exist. Vol NOT open. Vol NOT mounted. Vol already open. Files open on vol. Dirs open on vol. 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 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. FS_ERR_VOL_LABEL_INVALID FS_ERR_VOL_LABEL_NOT_FOUND FS_ERR_VOL_LABEL_TOO_LONG Volume label is invalid. Volume label was not found. Volume label is too long. 381 C/FS Error Codes 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. 382 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. 383 C/FS Porting Manual &ON &)6 3ODWIRUP,QGHSHQGHQW &38 &)6'ULYHUV ,'( 'ULYHU $7$+RVW &RQWUROOHU 1$1' 'ULYHU 125 'ULYHU 1$1' 'HYLFH 5726 125 'HYLFH 6'00& 'ULYHU 6'00& +RVW &RQWUROOHU 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. 384 C/FS Porting Manual FC-1(5) The IDE/CF driver can be ported to any ATA host controller or bus interface. FC-1(6) The NAND driver can be ported for many physical organizations (page size, bus width, etc.). FC-1(7) 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(8) The NAND driver can be ported to any SPI peripheral (for SPI flash). 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). FC-1(12) The SD/MMC driver can be ported to any SD/MMC host controller for cardmode access. FC-1(13) The SD/MMC driver can be ported to any SPI peripheral for SPI mode access. 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. 385 C/FS Porting Manual 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. 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. 386 C/FS Porting Manual 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. 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. 387 C/FS Porting Manual 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. #if (FS_CFG_WORKING_DIR_EN == DEF_ENABLED) CPU_CHAR *FS_OS_WorkingDirGet (void) { OS_ERR os_err; CPU_INT32U reg_val; CPU_CHAR *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) (1) (2) { OS_ERR os_err; CPU_INT32U reg_val; reg_val = (CPU_INT32U)p_working_dir; OSTaskRegSet((OS_TCB *) 0, FS_OS_REG_ID_WORKING_DIR, reg_val, &os_err); (void)&os_err; } #endif Listing C-1 FS_OS_WorkingDirGet()/Set() (C/OS-III) LC-1(1) 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 388 C/FS Porting Manual 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. 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. 389 C/FS Porting Manual 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) { /* $$$$ Insert code to delay for specified number of millieconds. */ } Listing C-3 FS_OS_Dly_ms() 390 C/FS Porting Manual FS_OS_Sem####() The four generic OS semaphore functions provide a complete abstraction of a basic OS kernel service. FS_OS_SemCreate() creates a semaphore which may later be deleted with FS_OS_SemDel(). FS_OS_SemPost() signals the semaphore (with or without timeout) and FS_OS_SemPend() waits until the semaphore is signaled. On systems without an OS kernel, the trivial implementations in Listing C-4 are recommended. CPU_BOOLEAN FS_OS_SemCreate (FS_BSP_SEM CPU_INT16U *p_sem, cnt) (1) { *p_sem = cnt; return (DEF_OK); /* $$$$ Create semaphore with initial count 'cnt'. */ } CPU_BOOLEAN FS_OS_SemDel (FS_BSP_SEM *p_sem) { *p_sem = 0u; /* $$$$ Delete semaphore. */ return (DEF_OK); } (2) Listing C-4 FS_OS_Sem####() trivial implementations 391 C/FS Porting Manual CPU_BOOLEAN FS_OS_SemPend (FS_BSP_SEM CPU_INT32U *p_sem, (3) timeout) { CPU_INT32U timeout_cnts; CPU_INT16U sem_val; CPU_SR_ALLOC(); if (timeout == 0u) { sem_val = 0u; while (sem_val == 0u) { CPU_CRITICAL_ENTER(); sem_val = *p_sem; /* $$$$ If semaphore available ... if (sem_val > 0u) { *p_sem = sem_val - 1u; /* ... decrement semaphore count. } CPU_CRITICAL_EXIT(); } } else { timeout_cnts = timeout * FS_BSP_CNTS_PER_MS; sem_val = 0; while ((timeout_cnts > 0u) && (sem_val == 0u)) { CPU_CRITICAL_ENTER(); sem_val = *p_sem; if (sem_val > 0) { *p_sem = sem_val - 1u; } CPU_CRITICAL_EXIT(); timeout_cnts--; */ */ /* $$$$ If semaphore available ... */ /* */ ... decrement semaphore count. } } if (sem_val == 0u) { return (DEF_FAIL); } else { return (DEF_OK); } } Listing C-5 FS_OS_Sem####() trivial implementations (continued) LC-5(1) FS_OS_SemCreate() creates a semaphore in the variable p_sem. For this trivial implementation, FS_BSP_SEM is a integer type which stores the current count, i.e., the number of objects available. LC-5(2) FS_OS_SemDel() deletes a semaphore created by FS_OS_SemCreate(). 392 C/FS Porting Manual CPU_BOOLEAN FS_OS_SemPost (FS_BSP_SEM *p_sem) { CPU_INT16U sem_val; CPU_SR_ALLOC(); CPU_CRITICAL_ENTER(); sem_val = *p_sem; /* $$$$ 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. 393 C/FS Porting Manual 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). 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. 394 C/FS Porting Manual Function Description IO_Ctrl() Execute device I/O control operation. Table C-1 Device Driver API Functions 395 C/FS Porting Manual 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. 396 C/FS Porting Manual 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. 397 C/FS Porting Manual 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 FS_ERR_DEV_INVALID_UNIT_NBR FS_ERR_DEV_IO FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_TIMEOUT FS_ERR_MEM_ALLOC 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. Device unit number is invalid. Device I/O error. Device unit is not present. Device timeout. Memory could not be allocated. RETURNED VALUE None. 398 C/FS Porting Manual 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. 399 C/FS Porting Manual 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. 400 C/FS Porting Manual 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. RETURNED VALUE None. 401 C/FS Porting Manual 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. 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 402 C/FS Porting Manual 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. 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. 403 C/FS Porting Manual 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. 404 C/FS Porting Manual For more information about the FS_DEV_INFO structure, see section D-2 "FS_DEV_INFO" on page 510. 405 C/FS Porting Manual 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 FS_ERR_DEV_INVALID_IO_CTRL FS_ERR_DEV_INVALID_UNIT_NBR FS_ERR_DEV_IO FS_ERR_DEV_NOT_OPEN FS_ERR_DEV_NOT_PRESENT FS_ERR_DEV_TIMEOUT Control operation performed successfully. I/O control operation unknown to driver. Device unit number is invalid. Device I/O error. Device is not open. Device is not present. Device timeout. RETURNED VALUE None. 406 C/FS Porting Manual 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. FS_DEV_IO_CTRL_REFRESH Refresh device. b. FS_DEV_IO_CTRL_LOW_FMT Low-level format device. c. FS_DEV_IO_CTRL_LOW_MOUNT Low-level mount device. d. FS_DEV_IO_CTRL_LOW_UNMOUNT Low-level unmount device. e. FS_DEV_IO_CTRL_LOW_COMPACT Low-level compact device. f. FS_DEV_IO_CTRL_LOW_DEFRAH Low-level defragment device. g. FS_DEV_IO_CTRL_SEC_RELEASE Release data in sector h. FS_DEV_IO_CTRL_PHY_RD Read physical device i. FS_DEV_IO_CTRL_PHY_WR Write physical device j. FS_DEV_IO_CTRL_PHY_RD_PAGE Read physical device page k. FS_DEV_IO_CTRL_PHY_WR_PAGE Write physical device page l. FS_DEV_IO_CTRL_PHY_ERASE_BLK Erase physical device block m. FS_DEV_IO_CTRL_PHY_ERASE_CHIP 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. 407 C/FS Porting Manual C-5 IDE/CF DEVICE BSP If you use and IDE/CF device, a driver is already available for C/FS. A BSP is required so that the IDE driver will work on a particular system. The port includes one code file: FS_DEV_IDE_BSP.C 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\IDE\<manufacturer>\<board name> Each BSP must implement the functions in Table C-2. Function Description FSDev_IDE_BSP_Open() Open (initialize) hardware. FSDev_IDE_BSP_Close() Close (uninitialize) hardware. FSDev_IDE_BSP_Lock() Acquire IDE bus lock. FSDev_IDE_BSP_Unlock() Release IDE bus lock. FSDev_IDE_BSP_Reset() Hardware-reset IDE device FSDev_IDE_BSP_RegRd() Read from IDE device register. FSDev_IDE_BSP_RegWr() Write to IDE device register. FSDev_IDE_BSP_CmdWr() Write command to IDE device register. FSDev_IDE_BSP_DataRd() Read data from IDE device. FSDev_IDE_BSP_DataWr() Write data to IDE device. FSDev_IDE_BSP_DMA_Start() Setup DMA for command (Initialize channel). FSDev_IDE_BSP_DMA_End() End DMA transfer (and uninitialize channel). FSDev_IDE_BSP_GetDrvNbr() Get IDE drive number. FSDev_IDE_BSP_GetModesSupported() Get supported transfer modes. FSDev_IDE_BSP_SetMode() Set transfer modes. FSDev_IDE_BSP_Dly400_ns() Delay for 400 ns. 408 C/FS Porting Manual Table C-2 IDE/CF BSP Functions Start No DMA Command? Yes Write command FSDev_IDE_BSP_CmdWr() Setup DMA FSDev_IDE_BSP_DMA_Start() Wait for data request Write command FSDev_IDE_BSP_CmdWr() Read or write data FSDev_IDE_BSP_DataRd/Wr() End DMA FSDev_IDE_BSP_DMA_End() More data? Yes No Check for error Return Figure C-2 Command Execution 409 C/FS Porting Manual C-5-1 FSDev_IDE_BSP_Open() CPU_BOOLEAN FSDev_IDE_BSP_Open (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_ide_bsp.c FSDev_IDE_Refresh() N/A Initialize IDE/CF hardware. ARGUMENTS unit_nbr Unit number of IDE/CF device. RETURNED VALUE DEF_OK, if interface was opened DEF_FAIL, otherwise NOTES/WARNINGS This function will be called every time the IDE/CF device is opened. 410 C/FS Porting Manual C-5-2 FSDev_IDE_BSP_Close() void FSDev_IDE_BSP_Close (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_ide_bsp.c FSDev_IDE_Close() N/A Uninitialize IDE/CF hardware. ARGUMENTS unit_nbr Unit number of IDE/CF device. RETURNED VALUE None. NOTES/WARNINGS This function will be called every time the IDE/CF device is closed. 411 C/FS Porting Manual C-5-3 FSDev_IDE_BSP_Lock() / FSDev_IDE_BSP_Unlock() void FSDev_IDE_BSP_Lock (FS_QTY unit_nbr); void FSDev_IDE_BSP_Unlock (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_ide_bsp.c various N/A Acquire/release IDE/CF bus lock. ARGUMENTS unit_nbr Unit number of IDE/CF device. RETURNED VALUE None. NOTES/WARNINGS FSDev_IDE_BSP_Lock() will be called before the IDE/CF driver begins to access the IDE/CF bus. The application should NOT use the same bus to access another device until the matching call to FSDev_IDE_BSP_Unlock() has been made. 412 C/FS Porting Manual C-5-4 FSDev_IDE_BSP_Reset() void FSDev_IDE_BSP_Reset (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_ide_bsp.c FSDev_IDE_Refresh() N/A Hardware-reset the IDE/CF device. ARGUMENTS unit_nbr Unit number of IDE/CF device. RETURNED VALUE None. NOTES/WARNINGS None. 413 C/FS Porting Manual C-5-5 FSDev_IDE_BSP_RegRd() CPU_INT08U FSDev_IDE_BSP_RegRd (FS_QTY unit_nbr, CPU_INT08U reg); File Called from Code enabled by fs_dev_ide_bsp.c various N/A Read from IDE/CF device register. ARGUMENTS unit_nbr Unit number of IDE/CF device. reg Register to read: FS_DEV_IDE_REG_ERR FS_DEV_IDE_REG_SC FS_DEV_IDE_REG_SN FS_DEV_IDE_REG_CYL FS_DEV_IDE_REG_CYH FS_DEV_IDE_REG_DH FS_DEV_IDE_REG_CMD FS_DEV_IDE_REG_ALTSTATUS Error Register. Sector Count Register. Sector Number Register. Cylinder Low Register. Cylinder High Register. Card/Drive/Head Register. Command Register. Alternate Status Register. RETURNED VALUE Register value. NOTES/WARNINGS None. 414 C/FS Porting Manual C-5-6 FSDev_IDE_BSP_RegWr() void FSDev_IDE_BSP_RegWr (FS_QTY unit_nbr, CPU_INT08U reg, CPU_INT08U val); File Called from Code enabled by fs_dev_ide_bsp.c various N/A Write to IDE/CF device register. ARGUMENTS unit_nbr Unit number of IDE/CF device. reg Register to read: FS_DEV_IDE_REG_FR FS_DEV_IDE_REG_SC FS_DEV_IDE_REG_SN FS_DEV_IDE_REG_CYL FS_DEV_IDE_REG_CYH FS_DEV_IDE_REG_DH FS_DEV_IDE_REG_CMD FS_DEV_IDE_REG_DEVCTRL val Features Register. Sector Count Register. Sector Number Register. Cylinder Low Register. Cylinder High Register. Card/Drive/Head Register. Command Register. Device Control Register. Value to write into register. RETURNED VALUE None. NOTES/WARNINGS None. 415 C/FS Porting Manual C-5-7 FSDev_IDE_BSP_CmdWr() void FSDev_IDE_BSP_CmdWr (FS_QTY unit_nbr, CPU_INT08U cmd[]); File Called from Code enabled by fs_dev_ide_bsp.c FSDev_IDE_RdData() FSDev_IDE_WrData() N/A Write 7-byte command to IDE/CF device registers. ARGUMENTS unit_nbr Unit number of IDE/CF device. cmd Array holding command. RETURNED VALUE None. NOTES/WARNINGS The 7 bytes of the command should be written to the IDE device registers as follows: REG_FR REG_SC REG_SN REG_CYL REG_CYN REG_DH REG_CMD = = = = = = = cmd[0] cmd[1] cmd[2] cmd[3] cmd[4] cmd[5] cmd[6] 416 C/FS Porting Manual C-5-8 FSDev_IDE_BSP_DataRd() void FSDev_IDE_BSP_DataRd (FS_QTY unit_nbr, void *p_dest, CPU_SIZE_T cnt); File Called from Code enabled by fs_dev_ide_bsp.c FSDev_IDE_RdData() N/A Read data from IDE/CF device. ARGUMENTS unit_nbr Unit number of IDE/CF device. p_dest Pointer to destination memory buffer. cnt Number of octets of data to read. RETURNED VALUE None. NOTES/WARNINGS None. 417 C/FS Porting Manual C-5-9 FSDev_IDE_BSP_DataWr() void FSDev_IDE_BSP_DataRd (FS_QTY unit_nbr, void *p_src, CPU_SIZE_T cnt); File Called from Code enabled by fs_dev_ide_bsp.c FSDev_IDE_WrData() N/A Write data to IDE/CF device. ARGUMENTS unit_nbr Unit number of IDE/CF device. p_src Pointer to source memory buffer. cnt Number of octets of data to write. RETURNED VALUE None. NOTES/WARNINGS None. 418 C/FS Porting Manual C-5-10 FSDev_IDE_BSP_DMA_Start() void FSDev_IDE_BSP_DMA_Start (FS_QTY unit_nbr, void *p_data, CPU_SIZE_T cnt, FS_FLAGS mode_type, CPU_BOOLEAN rd); File Called from Code enabled by fs_dev_ide_bsp.c FSDev_IDE_RdData() FSDev_IDE_WrData() N/A Setup DMA for command (initialize channel). ARGUMENTS unit_nbr Unit number of IDE/CF device. p_data Pointer to memory buffer. cnt Number of octets to transfer. mode_type Transfer mode type: FS_DEV_IDE_MODE_TYPE_DMA FS_DEV_IDE_MODE_TYPE_UDMA rd Multiword DMA mode. Ultra-DMA mode. Indicates whether transfer is read or write: DEF_YES DEF_NO Transfer is read. Transfer is write. RETURNED VALUE None. 419 C/FS Porting Manual NOTES/WARNINGS DMA setup occurs before the command is executed (in FSDev_IDE_BSP_CmdWr()). Afterwards, data transmission completion must be confirmed (in FSDev_IDE_BSP_DMA_End()) before the driver checks the command status. If the return value of FSDev_IDE_BSP_GetModesSupported() does not include FS_DEV_IDE_MODE_TYPE_DMA or FS_DEV_IDE_MODE_TYPE_UDMA, this function need not be implemented; it will never be called. C-5-11 FSDev_IDE_BSP_DMA_End() void FSDev_IDE_BSP_DMA_End (FS_QTY unit_nbr, void *p_data, CPU_SIZE_T cnt, CPU_BOOLEAN rd); File Called from Code enabled by fs_dev_ide_bsp.c FSDev_IDE_RdData() FSDev_IDE_WrData() N/A Setup DMA for command (initialize channel). ARGUMENTS unit_nbr Unit number of IDE/CF device. p_data Pointer to memory buffer. cnt Number of octets to transfer. rd Indicates whether transfer was read or write: DEF_YES DEF_NO Transfer was read. Transfer was write. 420 C/FS Porting Manual RETURNED VALUE None. NOTES/WARNINGS DMA setup occurs before the command is executed (in FSDev_IDE_BSP_CmdWr()). Afterwards, data transmission completion must be confirmed (in FSDev_IDE_BSP_DMA_End()) before the driver checks the command status. When this function returns, the host controller should be setup to transmit commands in PIO mode. If the return value of FSDev_IDE_BSP_GetModesSupported() does not include FS_DEV_IDE_MODE_TYPE_DMA or FS_DEV_IDE_MODE_TYPE_UDMA, this function need not be implemented; it will never be called. 421 C/FS Porting Manual C-5-12 FSDev_IDE_BSP_GetDrvNbr() CPU_INT08U FSDev_IDE_BSP_GetDrvNbr (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_ide_bsp.c FSDev_IDE_Refresh() N/A Get IDE/CF driver number. ARGUMENTS unit_nbr Unit number of IDE/CF device. RETURNED VALUE Drive number (0 or 1). NOTES/WARNINGS Two IDE devices may be accessed on the same bus by setting the DEV bit of the drive/head register. If the bit should be clear, this function should return 0; if the bit should be set, this function should return 1. 422 C/FS Porting Manual C-5-13 FSDev_IDE_BSP_GetModesSupported() FS_FLAGS FSDev_IDE_BSP_GetModesSupported (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_ide_bsp.c FSDev_IDE_Refresh() N/A Get supported transfer modes. ARGUMENTS unit_nbr Unit number of IDE/CF device. RETURNED VALUE Bit-mapped variable indicating supported transfer mode(s); should be the bitwise OR of one or more of: FS_DEV_IDE_MODE_TYPE_PIO PIO mode supported. FS_DEV_IDE_MODE_TYPE_DMA Multiword DMA mode supported. FS_DEV_IDE_MODE_TYPE_UDMA Ultra-DMA mode supported. NOTES/WARNINGS None. 423 C/FS Porting Manual C-5-14 FSDev_IDE_BSP_SetMode() CPU_INT08U FSDev_IDE_BSP_SetMode (FS_QTY unit_nbr, FS_FLAGS mode_type, CPU_INT08U mode); File Called from Code enabled by fs_dev_ide_bsp.c FSDev_IDE_Refresh() N/A Set transfer mode timings. ARGUMENTS unit_nbr Unit number of IDE/CF device. mode_type Transfer mode type. FS_DEV_IDE_MODE_TYPE_PIO FS_DEV_IDE_MODE_TYPE_DMA FS_DEV_IDE_MODE_TYPE_UDMA mode PIO mode. Multiword DMA mode. Ultra-DMA mode. Transfer mode, between 0 and maximum mode supported for mode type by device (inclusive).. RETURNED VALUE Mode selected; should be between 0 and mode, inclusive NOTES/WARNINGS If DMA is supported, two transfer modes will be setup. The first will be a PIO mode; the second will be a Multiword DMA or Ultra-DMA mode. Thereafter, the host controller or bus interface must be capable of both PIO and DMA transfers. 424 C/FS Porting Manual C-5-15 FSDev_IDE_BSP_Dly400_ns() CPU_INT08U FSDev_IDE_BSP_Dly400_ns (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_ide_bsp.c various N/A Delay 400-ns. ARGUMENTS unit_nbr Unit number of IDE/CF device. RETURNED VALUE None. NOTES/WARNINGS None. 425 C/FS Porting Manual C-6 NAND Flash Physical-Layer Driver The NAND 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 depending on the memory type and organization. The physical-layer driver is already available for different architectures and includes one code/header file pair named according to the following rubric: FS_DEV_NAND_<device_name>.C FS_DEV_NAND_<device_name>.H The physical-layer driver acts via a BSP. The generic drivers for traditional NAND flash require a BSP as described in Appendix C, "NAND Flash BSP" on page 440. The drivers for SPI flash (like Atmel Dataflash) require a SPI BSP as described in Appendix C, "NAND Flash SPI BSP" on page 450. 1$1''ULYHU IVBGHYBQDQGFK 3URYLGHVJHQHULFGULYHULQWHUIDFH HJ LQLWUHDGZULWH DQGSHUIRUPVZHDU OHYHOLQJVRDOOEORFNVDUHXVHGHTXDOO\ 3DUDOOHO,QWHUIDFH 6HULDO,QWHUIDFH 3K\VLFDO/D\HU'ULYHU IVBGHYBQDQGBB[ IVBGHYBQDQGBB[ 3K\VLFDO/D\HU'ULYHU IVBGHYBQDQGBDW IVBGHYBQDQGBB[ $FFHVVHV1$1'RQDEXVLQWHUIDFH %63 IVBGHYBQDQGBEVSF ,QLWLDOL]HXQLQLWLDO L]HUHDGZULWHRQWKH EXVLQWHUIDFH 1$1''HYLFH $FFHVVHV1$1'RQDQ63,LQWHUIDFH %63 IVBGHYBQDQGBEVSF ,QLWLDOL]HXQLQLWLDO L]HUHDGZULWHRQWKH 63,LQWHUIDFH 1$1''HYLFH Figure C-3 NAND Driver Architecture 426 C/FS Porting Manual Each physical-layer driver must implement the functions to be placed into a FS_DEV_NAND_PHY_API structure: const FS_DEV_NAND_PHY_API FSDev_NAND_PHY_Open, FSDev_NAND_#### { FSDev_NAND_PHY_Close, FSDev_NAND_PHY_RdPage, FSDev_NAND_PHY_RdSpare, FSDev_NAND_PHY_WrPage, FSDev_NAND_PHY_WrSpare, FSDev_NAND_PHY_CopyBack, FSDev_NAND_PHY_EraseBlk, FSDev_NAND_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_NAND_PHY_DATA structure which holds physical device information. Specific members will be described in subsequent sections as necessary. The NAND 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 NAND device and get NAND device information. Close() Close (uninitialize) a NAND device. RdPage() Read a page from a NAND device and store data in buffer. RdSpare() Read a spare area from a NAND device and store data in buffer. WrPage() Write to a page of a NAND device from data in buffer. WrSpare() Write to a spare area of a NAND device from data in buffer. WrCopyBack) Copy data from one block to another. EraseBlk() Erase block of NAND device. IO_Ctrl() Perform NAND device I/O control operation. 427 C/FS Porting Manual Table C-3 NAND flash physical-layer driver functions 428 C/FS Porting Manual C-6-1 Open() void Open (FS_DEV_NAND_PHY_DATA *p_phy_data, FS_ERR *p_err); File Called from Code enabled by NAND physical-layer driver FSDev_NAND_Open() N/A Open (initialize) a NAND device instance and get NAND device information. ARGUMENTS p_phy_data Pointer to NAND 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 UnitNbr is the unit number of the NAND device. 2 BlkCnt and BlkSize MUST be assigned the block count and block size of the device, respectively. A block is the device erase unit, e.g., the smallest area of the device that can be erased at any time. 3 PageSize MUST be assigned the page size of the device. A page is the device program unit, i.e., the smallest area of the device that can be programmed at any time. 4 BlkSize MUST be a multiple of PageSize. 5 PageSize MUST be a multiple of SecSize. 6 SpareSize MUST be assigned the size (in bytes) of the spare arear per sector. 429 C/FS Porting Manual 7 MaxClkFreq specifies the maximum SPI clock frequency. 8 BusWidth specify the bus configuration. 430 C/FS Porting Manual C-6-2 Close() void Close (FS_DEV_NAND_PHY_DATA *p_phy_data); File Called from Code enabled by NAND physical-layer driver FSDev_NAND_Close() N/A Close (uninitialize) a NAND device instance. ARGUMENTS p_phy_data Pointer to NAND phy data. RETURNED VALUE None. NOTES/WARNINGS None. 431 C/FS Porting Manual C-6-3 RdPage() void RdPage (FS_DEV_NAND_PHY_DATA void void FS_SEC_NBR FS_ERR *p_phy_data, *p_dest, *p_dest_spare, sec_nbr_phy, *p_err); File Called from Code enabled by NAND physical-layer driver FSDev_NAND_PhyRdSecHandler() N/A Read from a NAND device and store data in buffer. ARGUMENTS p_phy_data Pointer to NAND phy data. p_dest Pointer to destination buffer. p_dest_spare Pointer to destination spare buffer. sec_nbr_phy Physical sector to read from the page. 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_INVALID_ECC FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Octets read successfully. Device invalid operation. Invalid ECC. Device I/O error. Device timeout error. RETURNED VALUE None. 432 C/FS Porting Manual NOTES/WARNINGS None. 433 C/FS Porting Manual C-6-4 RdSpare() void RdSpare (FS_DEV_NAND_PHY_DATA *p_phy_data, void *p_dest, FS_SEC_NBR sec_nbr_phy, CPU_INT08U offset, CPU_INT08U bytes_nbr, FS_ERR *p_err); File Called from Code enabled by NAND physical-layer driver FSDev_NAND_PhyRdSpareHandler() N/A Read data from NAND page spare area and store data in buffer. ARGUMENTS p_phy_data Pointer to NAND phy data. p_dest Pointer to destination buffer. sec_nbr_phy offset Physical sector to read from the page. Offset in the spare area. bytes_nbr Number of bytes to read. 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 Octets read successfully. Device invalid operation. Device I/O error. Device timeout error. RETURNED VALUE None. 434 C/FS Porting Manual C-6-5 WrPage() void WrPage (FS_DEV_NAND_PHY_DATA void void FS_SEC_NBR FS_ERR *p_phy_data, *p_src, *p_src_spare, sec_nbr_phy, *p_err); File Called from Code enabled by NAND physical-layer driver FSDev_NAND_PhyWrSecHandler() N/A Write to a NAND device. ARGUMENTS p_phy_data Pointer to NAND phy data. p_src Pointer to source buffer. p_src_spare Pointer to source spare buffer. sec_nbr_phy Physical sector to write. 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 Octets written successfully. Device invalid operation. Device I/O error. Device timeout error. RETURNED VALUE None. NOTES/WARNINGS None. 435 C/FS Porting Manual C-6-6 WrSpare() void WrSpare (FS_DEV_NAND_PHY_DATA *p_phy_data, void *p_src, FS_SEC_NBR sec_nbr_phy, CPU_INT08U offset, CPU_INT08U bytes_nbr, FS_ERR *p_err); File Called from Code enabled by NAND physical-layer driver FSDev_NAND_PhyWrSpareHandler() N/A Write data to a NAND device page spare area. ARGUMENTS p_phy_data Pointer to NAND phy data. p_src Pointer to source buffer. sec_nbr_phy offset Sector number for which the spare area will be written. Offset in the spare area. bytes_nbr Number of bytes to write. 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 Octets written successfully. Device invalid operation. Device I/O error. Device timeout error. RETURNED VALUE None. 436 C/FS Porting Manual C-6-7 CopyBack() void CopyBack (FS_DEV_NAND_PHY_DATA *p_phy_data, CPU_INT32U src_page_nbr_phy, CPU_INT32U dest_page_nbr_phy, FS_ERR *p_err); File Called from Code enabled by NAND physical-layer driver N/A N/A Make internal copy back of page data. ARGUMENTS p_phy_data Pointer to NAND phy data. src_page_nbr_phy Source page number. dest_page_nbr_phy Destination page number. p_err Pointer to variable that will receive the return error code from this function. FS_ERR_NONE Page copied successfully. RETURNED VALUE None. NOTES/WARNINGS None. 437 C/FS Porting Manual C-6-8 EraseBlk() void EraseBlk (FS_DEV_NAND_PHY_DATA *p_phy_data, CPU_INT32U blk_nbr_phy, FS_ERR *p_err); File Called from Code enabled by NAND physical-layer driver FSDev_NAND_PhyEraseBlkHandler() N/A Erase block of NAND device. ARGUMENTS p_phy_data Pointer to NAND phy data. blk_nbr_phy p_err Block to erase. Pointer to variable that will receive the return error code from this function. FS_ERR_NONE FS_ERR_DEV_IO FS_ERR_DEV_TIMEOUT Block erased successfully. Device I/O error. Device timeout error. RETURNED VALUE None. NOTES/WARNINGS None. 438 C/FS Porting Manual C-6-9 IO_Ctrl() void IO_Ctrl (FS_DEV_NAND_PHY_DATA *p_phy_data, CPU_INT08U opt, void *p_data, FS_ERR *p_err); File Called from Code enabled by NAND physical-layer driver N/A N/A Perform NAND device I/O control operation. ARGUMENTS p_phy_data Pointer to NAND 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_DEV_INVALID_IO_CTRL I/O control unknown to driver. RETURNED VALUE None. NOTES/WARNINGS None. Table C-4 439 C/FS Porting Manual C-7 NAND Flash BSP The NAND driver must adapt to the specific hardware using a BSP. The following functions must be implemented to interface the NAND driver on a parallel bus. 440 C/FS Porting Manual C-7-1 FSDev_NAND_BSP_Open() CPU_BOOLEAN FSDev_NAND_BSP_Open (FS_QTY unit_nbr, CPU_INT08U bus_width); File Called from Code enabled by fs_dev_nand_bsp.c NAND physical-layer driver N/A Open (initialize) bus for NAND. ARGUMENTS unit_nbr Unit number of NAND. bus_width Bus width, in bits. RETURNED VALUE DEF_OK, if interface was opened. DEF_FAIL, otherwise. NOTES/WARNINGS This function will be called every time the device is opened. 441 C/FS Porting Manual C-7-2 FSDev_NAND_BSP_Close() void FSDev_NAND_BSP_Close (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_nand_bsp.c NAND physical-layer driver N/A Close (uninitialize) bus for NAND. ARGUMENTS unit_nbr Unit number of NAND. RETURNED VALUE None. NOTES/WARNINGS This function will be called every time the device is closed. 442 C/FS Porting Manual C-7-3 FSDev_NAND_BSP_ChipSelEn() void FSDev_NAND_BSP_ChipSelEn (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_nand_bsp.c NAND physical-layer driver N/A Enable NAND chip select / chip enable. ARGUMENTS unit_nbr Unit number of NAND. RETURNED VALUE None. NOTES/WARNINGS None. 443 C/FS Porting Manual C-7-4 FSDev_NAND_BSP_ChipSelDis() void FSDev_NAND_BSP_ChipSelDis (FS_QTY unit_nbr); File Called from Code enabled by fs_dev_nand_bsp.c NAND physical-layer driver N/A Disable NAND chip select / chip enable. ARGUMENTS unit_nbr Unit number of NAND. RETURNED VALUE None. NOTES/WARNINGS None. 444 C/FS Porting Manual C-7-5 FSDev_NAND_BSP_RdData() void FSDev_NAND_BSP_RdData (FS_QTY unit_nbr, void *p_dest); CPU_SIZE_T cnt); File Called from Code enabled by fs_dev_nand_bsp.c NAND physical-layer driver N/A Read data from NAND. ARGUMENTS unit_nbr Unit number of NAND. p_dest Pointer destination memory buffer. cnt Number of octets to read. RETURNED VALUE None. NOTES/WARNINGS None. 445 C/FS Porting Manual C-7-6 FSDev_NAND_BSP_WrAddr() void FSDev_NAND_BSP_WrAddr (FS_QTY unit_nbr, CPU_INT08U *p_addr); CPU_SIZE_T cnt); File Called from Code enabled by fs_dev_nand_bsp.c NAND physical-layer driver N/A Write address to NAND. ARGUMENTS unit_nbr Unit number of NAND. p_addr Pointer to buffer that holds address. cnt Number of octets to write. RETURNED VALUE None. NOTES/WARNINGS None. 446 C/FS Porting Manual C-7-7 FSDev_NAND_BSP_WrCmd() void FSDev_NAND_BSP_WrCmd (FS_QTY unit_nbr, CPU_INT08U *p_cmd); CPU_SIZE_T cnt); File Called from Code enabled by fs_dev_nand_bsp.c NAND physical-layer driver N/A Write command to NAND. ARGUMENTS unit_nbr Unit number of NAND. p_cmd Pointer to buffer that holds command. cnt Number of octets to write. RETURNED VALUE None. NOTES/WARNINGS None. 447 C/FS Porting Manual C-7-8 FSDev_NAND_BSP_WrData() void FSDev_NAND_BSP_WrData (FS_QTY unit_nbr, CPU_INT08U *p_src); CPU_SIZE_T cnt); File Called from Code enabled by fs_dev_nand_bsp.c NAND physical-layer driver N/A Write data to NAND. ARGUMENTS unit_nbr Unit number of NAND. p_src Pointer to source memory buffer cnt Number of octets to write. RETURNED VALUE None. NOTES/WARNINGS None. 448 C/FS Porting Manual C-7-9 FSDev_NAND_BSP_WaitWhileBusy() CPU_BOOLEAN FSDev_NAND_BSP_WaitWhileBusy (FS_QTY unit_nbr, FS_DEV_NAND_PHY_DATA *p_addr, CPU_BOOLEAN (*poll_fnct)(FS_DEV_NAND_PHY_DATA *), CPU_INT32U to_us); File Called from Code enabled by fs_dev_nand_bsp.c NAND physical-layer driver N/A Wait while NAND is busy. ARGUMENTS unit_nbr Unit number of NAND. p_phy_data Pointer to NAND 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. 449 C/FS Porting Manual C-8 NAND Flash SPI BSP The NAND driver must adapt to the specific hardware using a BSP. A serial NAND Flash will be interfaced on a SPI bus. See Appendix C, "SPI BSP" on page 494 for the details on how to implement the software port for your SPI bus. 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 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. 450 C/FS Porting Manual 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 459. The drivers for SPI flash require a SPI BSP as described in Appendix C, "NOR Flash SPI BSP" on page 466. fs_dev_nor.c/h Provides generic driver interface (e.g., init, read, write) and performs wearleveling so all blocks are used equally. Traditional NOR Serial NOR Physical-Layer Driver Physical-Layer Driver Implements particular NOR flash command set; accesses NOR directly on bus interface. Implements particular NOR flash command set; accesses NOR with SPI BSP. Bus interface BSP fs_dev_nor_bsp. c Initialize/uninitialize bus interface. NOR SPI BSP fs_dev_nor_bsp.c Access NOR via SPI. Figure C-4 NOR Driver Architecture Each physical-layer driver must implement the functions to be placed into a FS_DEV_NOR_PHY_API structure: const FS_DEV_NOR_PHY_API FSDev_NOR_#### { FSDev_NOR_PHY_Open, FSDev_NOR_PHY_Close, 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 451 C/FS Porting Manual 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 452 C/FS Porting Manual 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. 453 C/FS Porting Manual 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. 454 C/FS Porting Manual 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. 455 C/FS Porting Manual 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 Octets written successfully. Device I/O error. Device timeout error. RETURNED VALUE None. NOTES/WARNINGS None. 456 C/FS Porting Manual 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. 457 C/FS Porting Manual 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 Control operation performed successfully. control unknown to driver. Invalid operation for device. Device I/O error. Device timeout error. RETURNED VALUE None. NOTES/WARNINGS None. 458 C/FS Porting Manual 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 459 C/FS Porting Manual 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. 460 C/FS Porting Manual 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. 461 C/FS Porting Manual 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. 462 C/FS Porting Manual 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. 463 C/FS Porting Manual 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. 464 C/FS Porting Manual 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. 465 C/FS Porting Manual 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 time_cur_us; CPU_INT32U time_start_us; CPU_BOOLEAN rdy; time_cur_us = /* $$$$ GET CURRENT TIME, IN MICROSECONDS. */; time_start_us = time_cur_us; while (time_cur_us - time_start_us < to_us) { rdy = poll_fnct(p_phy_data); if (rdy == DEF_OK) { return (DEF_OK); } time_cur_us = /* $$$$ GET CURRENT TIME, IN MICROSECONDS. */; } return (DEF_FAIL); (1) (2) (3) } Listing C-7 FSDev_NOR_BSP_WaitWhileBusy() (without hardware read/busy signal) LC-7(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-7(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-7(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 494 for the details on how to implement the software port for your SPI bus. 466 C/FS Porting Manual C-12 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: \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. 467 C/FS Porting Manual Function Description 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-7 SD/MMC cardmode BSP functions Each BSP must implement the functions in Table C-7. (For information about creating a port for a platform accessing a SD/MMC device in SPI mode, see section C-13 "SD/MMC SPI mode BSP" on page 493) 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 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-5. 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. 468 C/FS Porting Manual 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-5 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. 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. 469 C/FS Porting Manual 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. C-12-1 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. 470 C/FS Porting Manual C-12-2 FSDev_SD_Card_BSP_Lock() FSDev_SD_Card_BSP_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. 471 C/FS Porting Manual C-12-3 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_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. 472 C/FS Porting Manual 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). 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: a. p_cmd->Cmd is the command index. b. p_cmd->Arg is the 32-bit argument (or 0 if there is no argument). c. 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 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. d. p_cmd->DataDir indicates the direction of any data transfer that should follow this command, if any: FS_DEV_SD_CARD_DATA_DIR_NONE No data transfer. FS_DEV_SD_CARD_DATA_DIR_HOST_TO_CARD Transfer host-to-card (write). FS_DEV_SD_CARD_DATA_DIR_CARD_TO_HOST Transfer card-to-host (read). 473 C/FS Porting Manual e. 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 No data transfer. Single data block. Multiple data blocks. Stream data. f. 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 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. g. 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. 3. 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. 474 C/FS Porting Manual void FSDev_SD_Card_BSP_CmdStart (FS_QTY FS_DEV_SD_CARD_CMD void FS_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; } } } 475 C/FS Porting Manual /* Write registers to exec cmd. */ REG_SDMA_ADDESS = p_data; REG_BLOCK_COUNT REG_BLOCK_SIZE REG_ARGUMENT = p_cmd->BlkCnt; = p_cmd->BlkSize; = p_cmd->Arg; (4) REG_TRANSFER_MODE = transfer_mode; REG_COMMAND = command; *p_err = FS_DEV_SD_CARD_ERR_NONE; } Listing C-8 FSDev_SD_Card_BSP_CmdStart() LC-8(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-8(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-8(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-8(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. 476 C/FS Porting Manual C-12-4 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_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 No error. No card present. Unknown or other error. Timeout in waiting for command response. FS_DEV_SD_CARD_ERR_RESP_TIMEOUT Timeout in receiving command response. FS_DEV_SD_CARD_ERR_RESP_CHKSUM Error in response checksum. FS_DEV_SD_CARD_ERR_RESP_CMD_IX Response command index error. FS_DEV_SD_CARD_ERR_RESP_END_BIT Response end bit error. FS_DEV_SD_CARD_ERR_RESP Other response error. FS_DEV_SD_CARD_ERR_DATA Other data error. RETURNED VALUE None. 477 C/FS Porting Manual 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. a. For a command with a normal (48-bit) response, a 4-byte response should be stored in p_resp. b. 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(). 478 C/FS Porting Manual void FSDev_SD_Card_BSP_CmdWaitEnd (FS_QTY FS_DEV_SD_CARD_CMD CPU_INT32U FS_ERR unit_nbr, *p_cmd, *p_resp, *p_err) { CPU_INT16U interrupt_status; CPU_INT16U error_status; CPU_INT16U timeout; 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; } 479 C/FS Porting Manual /* Read response. REG_INTERRUPT_STATUS = BIT_INTERRUPT_STATUS_COMMAND_COMPLETE; */ (3) 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-9 FSDev_SD_Card_BSP_CmdWaitEnd() LC-9(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-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) 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. 480 C/FS Porting Manual C-12-5 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_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 No error. FS_DEV_SD_CARD_ERR_NO_CARD No card present. FS_DEV_SD_CARD_ERR_UNKNOWN Unknown or other error. FS_DEV_SD_CARD_ERR_WAIT_TIMEOUT Timeout in waiting for data. FS_DEV_SD_CARD_ERR_DATA_OVERRUN Data overrun. FS_DEV_SD_CARD_ERR_DATA_TIMEOUT Timeout in receiving data. FS_DEV_SD_CARD_ERR_DATA_CHKSUM Error in data checksum. FS_DEV_SD_CARD_ERR_DATA_START_BIT Data start bit error. FS_DEV_SD_CARD_ERR_DATA Other data error. RETURNED VALUE None. NOTES/WARNINGS None. 481 C/FS Porting Manual EXAMPLE The implementation of FSDev_SD_Card_BSP_CmdDataRd() 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_CmdDataRd (FS_QTY FS_DEV_SD_CARD_CMD void FS_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-10 FSDev_SD_Card_BSP_CmdDataRd() 482 C/FS Porting Manual 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 to the memory buffer using DMA. 483 C/FS Porting Manual C-12-6 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_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 No error. FS_DEV_SD_CARD_ERR_NO_CARD No card present. FS_DEV_SD_CARD_ERR_UNKNOWN Unknown or other error. FS_DEV_SD_CARD_ERR_WAIT_TIMEOUT Timeout in waiting for data. FS_DEV_SD_CARD_ERR_DATA_UNDERRUN Data underrun. FS_DEV_SD_CARD_ERR_DATA_CHKSUM Error in data checksum. FS_DEV_SD_CARD_ERR_DATA_START_BIT Data start bit error. FS_DEV_SD_CARD_ERR_DATA Other data error. RETURNED VALUE None. NOTES/WARNINGS None. 484 C/FS Porting Manual EXAMPLE The implementation of FSDev_SD_Card_BSP_CmdDataWr() 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_CmdDataWr (FS_QTY FS_DEV_SD_CARD_CMD void FS_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-11 FSDev_SD_Card_BSP_CmdDataWr() 485 C/FS Porting Manual LC-11(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-11(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-11(3) Return no error. The data has been transferred already from the memory buffer using DMA. 486 C/FS Porting Manual C-12-7 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. 487 C/FS Porting Manual C-12-8 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. 488 C/FS Porting Manual C-12-9 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. 489 C/FS Porting Manual EXAMPLE The implementation of FSDev_SD_Card_BSP_SetBusWidth() in Listing C-12 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-12 FSDev_SD_Card_BSP_SetBusWidth() 490 C/FS Porting Manual C-12-10 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. 491 C/FS Porting Manual C-12-11 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. 492 C/FS Porting Manual C-12-12 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-13 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-14 "SPI BSP" on page 494 for the details on how to implement the software port for your SPI bus. 493 C/FS Porting Manual C-14 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-8 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-6 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: 494 C/FS Porting Manual 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. 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. 495 C/FS Porting Manual Figure C-6 Example SPI transaction 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: 496 C/FS Porting Manual 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-9. 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 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-9 SPI port functions 497 C/FS Porting Manual 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. 498 C/FS Porting Manual C-14-1 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 3 For a SD/MMC card, the following settings should be used: 499 C/FS Porting Manual 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 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. 500 C/FS Porting Manual C-14-2 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. 501 C/FS Porting Manual C-14-3 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. 502 C/FS Porting Manual C-14-4 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. 503 C/FS Porting Manual C-14-5 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. 504 C/FS Porting Manual C-14-6 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. 505 C/FS Porting Manual C-14-7 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. 506 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. 507 C/FS Types and Structures 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. 508 C/FS Types and Structures 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. 509 C/FS Types and Structures 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 Device is closed. Device is closing. Device is opening. Device is open, but not present. Device is present, but not formatted. FS_DEV_STATE_LOW_FMT_VALID 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. low-level NOTES None. 510 C/FS Types and Structures D-3 FS_DEV_NAND_CFG typedef struct fs_dev_nand_cfg { CPU_INT32U BlkNbrFirst; FS_SEC_SIZE SecSize; CPU_INT32U BlkCnt; CPU_INT08U RBCnt; FS_DEV_NAND_PHY_API *PhyPtr; CPU_INT08U BusWidth; CPU_INT32U MaxClkFreq; } FS_DEV_NAND_CFG; File Used for fs_dev_nand.h Second argument of FSDev_Open() (when opening a NAND device) Configures the properties of a NAND device that will be opened. A pointer to this structure is passed as the second argument of FSDev_Open() for a NAND device. MEMBERS BlkNbrFirst MUST specify which block of the NAND flash memory will be the first used for the file system data. SecSize MUST specify the sector size in bytes for the NAND flash (either 512, 1024, 2048 or 4096). BlkCnt MUST specify the size of the NAND flash in number of blocks. RBCnt MUST specify the number of replacement blocks that will be used by the driver. PhyPtr MUST point to the appropriate physical-layer driver: FSDev_NAND_0512x08 FSDev_NAND_2048x08 FSDev_NAND_2048x16 FSDev_NAND_AT45 512-byte page NAND, 8-bit data bus. 2048-byte page NAND, 8-bit data bus. 2048-byte page NAND, 16-bit data bus. Atmel AT45 serial DataFlash 511 C/FS Types and Structures Other BusWidth User-developed is the bus width, in bits, between the MCU/MPU and each connected device. MaxClkFreq For a serial flash, the maximum clock frequency is specified via MaxClkFreq. NOTES None. 512 C/FS Types and Structures D-4 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). 513 C/FS Types and Structures 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 FSDev_NOR_STM25 FSDev_NOR_SST25 Other 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 ST M25 serial flash SST SST25 serial flash User-developed 514 C/FS Types and Structures For a parallel NOR, the bus configuration is specified via BusWidth, BusWidthMax and PhyDevCnt: BusWidth BusWidthMax PhyDevCnt is the bus width, in bits, between the MCU/MPU and each connected device. is the maximum width supported by each connected device. is the number of devices interleaved on the bus. For a serial flash, the maximum clock frequency is specified via MaxClkFreq. NOTES None. 515 C/FS Types and Structures D-5 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. 516 C/FS Types and Structures D-6 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 510 NOTES None. 517 C/FS Types and Structures D-7 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 7-2-1 "File and Directory Attributes" on page 104). 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. 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. 518 C/FS Types and Structures NOTES None. 519 C/FS Types and Structures D-8 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 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. 520 C/FS Types and Structures 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 9, "File Systems: FAT" on page 109. 521 C/FS Types and Structures D-9 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. 522 C/FS Types and Structures D-10 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 Device is closed. Device is closing. Device is opening. Device is open, but not present. Device is present, but not formatted. low-level 523 C/FS Types and Structures FS_DEV_STATE_LOW_FMT_VALID Device low-level format is valid. 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. 524 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. 525 C/FS Configuration E-1 FILE SYSTEM CONFIGURATION Core file system modules may be selectively disabled. 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_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(). 526 C/FS Configuration 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 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 527 C/FS Configuration 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 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. 528 C/FS Configuration 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 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 mutliple times and without proection. 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 filesystem 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 529 C/FS Configuration Function File 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 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. 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). 530 C/FS Configuration 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. 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. 531 C/FS Configuration 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.: E-6 FILE SYSTEM COUNTER CONFIGURATION C/FS contains code that increments coutners 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. 532 C/FS Configuration 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. 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. 533 C/FS Configuration E-9 TRACE CONFIGURATION The file system debug trace is enabled by #define`ing FS_TRACE_LEVEL in your application's app_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 534 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 535 Shell Commands 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, "Directories and Files" on page 28, 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. 536 Shell Commands 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 537 Shell Commands 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 SHELL_ERR SHELL_CMD_PARAM CPU_CHAR cmd_line[MAX_CMD_LEN]; 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 (see Note #2). */ /* Exec cmd (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) { /* $$$$ Store line from terminal/command line into `pbuf'; return length of line. */ } 538 Shell Commands /* ************************************************************************************** * App_ShellOut() ******************************************************************************1******* */ CPU_INT16S App_ShellOut (CPU_CHAR CPU_INT16U void *pbuf, buf_len, *popt) { /* $$$$ 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(). 539 Shell Commands 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 540 Shell Commands 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. 541 Shell Commands 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 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. 542 Shell Commands 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. 543 Shell Commands 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. 544 Shell Commands 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: where the the the 2nd the the 1st dd hh mm ccyy mm is the is the is the is the is 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 545 Shell Commands F-3-5 fs_df Report disk free space. USAGES fs_df fs_df [vol] ARGUMENTS volIf 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 546 Shell Commands 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 547 Shell Commands 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. 548 Shell Commands 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. 549 Shell Commands 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. 550 Shell Commands 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. 551 Shell Commands 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 552 Shell Commands 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. 553 Shell Commands 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. 554 Shell Commands 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. 555 Shell Commands 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. 556 Shell Commands 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. 557 Shell Commands 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 558 Shell Commands 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. FS_FAT_CFG_CMD_RM_EN Enable/disable fs_rm. a particular fs_#### 559 Shell Commands 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. 560 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. 561 Appendix G G 562 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 Micrim 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 563 Appendix H H-1-2 C/FS MAINTENANCE RENEWAL H 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 Micrim Micrim 1290 Weston Road, Suite 306 Weston, FL 33326 +1 954 217 2036 +1 954 217 2037 (FAX) 564 Mouser Electronics Authorized Distributor Click to View Pricing, Inventory, Delivery & Lifecycle Information: Analog Devices Inc.: AD-UCFS-MJRN-SP AD-UCFS-MNT-SP