blks 0, 1, 2, 3; Y = 0001 protects Group1 = blks 4, 5, 6, 7; Y = 1011 protects Group11 =
blks 44, 45, 46, 47.
PROTECTION Command Details
To enable protection, four bus write cycles set up the 4Ch, 03h, 1Dh, and 41h com-
mands. Next, one bus write cycle sets up the PAGE PROGRAM command (80h).
Then, five bus write cycles are required to input the targeted block group information:
00h, 00h, 00h, 0Yh, 00h. In this 4th address cycle, 0Yh is the last 4 bits and represents the
group of blocks to be protected. There are always 12 Groups, so Y = 0000b-1011b:
• Y = 0000 protects Group0 = blks 0, 1, 2, 3
• Y = 0001 protects Group1 = blks 4, 5, 6, 7
• Y = 1011 protects Group11 = blks 44, 45, 46, 47
One bus cycle is required to issue the PAGE PROGRAM CONFIRM command. After
tProg, the targeted block groups are protected. The EXIT PROTECTION command (FFh)
is issued to ensure the device exits protection mode.
(4Ch-03h-1Dh-41h)-80h-addr(00h-00h-00h-0Yh-00h)-10h-tPROG-FFh
The enable protection step is four bytes wide to prevent implementing involuntary pro-
tection. In addition, any spurious command/address/data cycles between each byte in-
validates the entire process and the next PROGRAM command does not affect the block
protection status. Likewise, any spurious command/address/data cycle between enable
protection and setting up the PAGE PROGRAM command invalidates the entire protec-
tion command process.
If enable protection is followed by an operation other than the PROGRAM operation,
such as a PAGE READ or BLOCK ERASE operation, this other operation is executed
without affecting block protection status. Therefore, the PROTECT operation must still
be executed to protect the block. The PROTECT operation is inhibited if WP# is LOW.
Upon PROTECT operation failure, the status register reports a value of E1h. Upon PRO-
TECT operation success, the status register reports value of E0h.
The following is an example of boot block protection:
Protect group 5 (blks20-23): (4Ch-03h-1Dh-41h)-80h-addr(00h-00h-00h-05h-00h)-10h-
tPROG-FFh
Addendum: NAND Valid Blocks and Boot Block Protection
PROTECT Command
PDF: X26P4QTWDSPK-13-10296
addendum_valid_boot_block_protection_m7xAseries_NAND.pdf - Rev. D 1/16 EN 3Micron Technology, Inc. reserves the right to change products or specifications without notice.
© 2012 Micron Technology, Inc. All rights reserved.