M29W800AT STMICROELECTRONICS [STMicroelectronics], M29W800AT Datasheet - Page 33

• Manufacturer Part Number: M29W800AT
• Description: 8 Mbit (1Mb x8 or 512Kb x16, Boot Block) Low Voltage Single Supply Flash Memory
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

SECURITY PROTECTION MEMORY AREA
The M29W800A features a security protection
memory area. It consists of a memory block of 256
bytes or 128 words which is programmed in the ST
factory to store a unique code that uniquely identi-
fies the part.
This memory block can be read by using the Read
Security Data instruction (RDS) as shown in Table
23.
Table 23. Security Block Instruction
Note: 1. Address bits A10-A19 are don't care for coded address inputs.
Figure 17. Security Block Address Table
Mne.
RDS
2. Data bits DQ8-DQ15 are don't care for coded address inputs.
Read
Security
Data
Instr.
000FFh
0007Fh
00000h
00000h
Cyc.
1
TOP BOOT BLOCK
TOP BOOT BLOCK
Memory Block
Memory Block
Addr.
Data
Security
Security
(2)
(1)
WORD Organisation (x16)
Unlock Cycle
BYTE Organisation (x8)
1st Cyc.
AAh
B8h
Read Security Data (RDS) Instruction. This RDS
uses a single write cycle instruction: the command
B8h is written to the address AAh. This sets the
memory to the Read Security mode. Any succes-
sive read attempt will output the addressed Secu-
rity byte until a new write cycle is initiated.
Read OTP Data until a new write cycle is initiated.
BOTTOM BOOT BLOCK
BOTTOM BOOT BLOCK
Memory Block
Memory Block
Security
Security
M29W800AT, M29W800AB
2nd Cyc.
AI02746
0E0FFh
0E000h
0E01Fh
0E000h
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