256Mb: 3V Embedded Parallel NOR Flash
READ and AUTO SELECT Operations
tables or the Block Protection tables, respectively. If the block is protected, then 01h is
output on data input/outputs DQ0-DQ7, otherwise 00h is output.
Three consecutive bus WRITE operations are required to issue an AUTO SELECT com-
mand. The device remains in auto select mode until a READ/RESET or READ CFI com-
mand is issued.
The device cannot enter auto select mode when a PROGRAM or ERASE operation is in
progress (RY/BY# LOW) unless the respective operation is suspended by a PROGRAM
SUSPEND or an ERASE SUSPEND command.
Auto select mode is exited by performing a reset. The device returns to read mode un-
less it entered auto select mode after an ERASE SUSPEND or PROGRAM SUSPEND
command, in which case it returns to erase or program suspend mode.
Table 15: Read Electronic Signature, Auto Select Mode and Programmer Method
Address inputs
Data IO
Read cycle1
E# G# W# A[23:10] A[9:8] A[7:5] A4 A3 A2 A1 A0 DQ[15:0]
Manufacturer code
Device code (cycle 1)
Device code (cycle 2)
Device code (cycle 3)
VIL VIL VIH
X
X
VIL
X
X
VIL
VIL
VIL
VIL
VIL
VIL
0020h
227Eh
223Ch
2202h
VIL VIH
VIH VIH VIH VIL
VIH VIH VIH VIH
1. X = VIL or VIH.
Note:
Table 16: Block protection (16-bit mode)
Address inputs
Data IO
VPP
/
E# G# W# RST# WP# A[23:12] A[11:10] A9 A8 A7 A6 A[5:4] A[3:2] A1 A0
Operation: Verify extended memory block indicator bit
Bits
Value
VIL VIL VIH VIH
VIH
BKA
X
X
X
VIL VIL
VIL
VIL VIH VIH DQ[15:8]
0
DQ7
DQ6
1 = factory locked
1 = customer locked,
0 = customer lockable
DQ5
1 = reserved,
0 = standard
DQ[4:3] 00 = WP# protects 4
outermost blocks,
11 = No WP# protection
(hardware write
protection)
DQ[2:0]
0
Operation: Verify block protection status
VIL VIL VIH VIH
VIH
BAd
X
X
X
VIL VIL
VIL
VIL VIH VIL
0000h (unprotected)
0001h (protected)
1. X = VIL or VIH. BAd any address in the block, BKA bank address.
Note:
PDF: 09005aef84ecabef
m29dw_256g.pdf - Rev. A 10/12 EN
Micron Technology, Inc. reserves the right to change products or specifications without notice.
31
© 2012 Micron Technology, Inc. All rights reserved.