W29N02GVSIAA Datasheet, PDF (31/79 Pages) Winbond – W29N02GV 2G-BIT 3.3V NAND FLASH MEMORY

W29N02GV
9.1.9 READ UNIQUE ID (EDh)
The W29N02GV NAND Flash device has a method to uniquely identify each NAND Flash device by
using the READ UNIQUE ID command. The format of the ID is limitless, but the ID for every NAND
Flash device manufactured, will be guaranteed to be unique.
Numerous NAND controllers typically use proprietary error correction code (ECC) schemes. In these
cases Winbond cannot protect unique ID data with factory programmed ECC. However, to ensure
data reliability, Winbond will program the NAND Flash devices with 16 bytes of unique ID code,
starting at byte 0 on the page, immediately followed by 16 bytes of the complement of that unique ID.
The combination of these two actions is then repeated 16 times. This means the final copy of the
unique ID will resides at location byte 511. At this point an XOR or exclusive operation can be
performed on the first copy of the unique ID and its complement. If the unique ID is good, the results
should yield all the bits as 1s. In the event that any of the bits are 0 after the XOR operation, the
procedure can be repeated on a subsequent copy of the unique ID data.
CLE
#WE
ALE
#RE
I/Ox
EDh
00h
RY/#BY
Byte0
Byte1
Byte14
Byte15
tR
Unique ID data
Figure 9-11 Read Unique ID
Release Date: February 1^st, 2016
31
– Revision B