M24C16-A125 Datasheet, PDF (16/37 Pages) STMicroelectronics – Automotive 16-Kbit serial IC bus EEPROM with 1 MHz clock

Instructions
M24C16-A125
4.1.3
4.1.4
Write Identification Page
The Identification Page (16 bytes) is an additional page which can be written and (later)
permanently locked in Read-only mode. It is written by issuing the Write Identification Page
instruction. This instruction uses the same protocol and format as Page Write (into memory
array), except for the following differences:
• Device type identifier = 1011b
• Most significant address bits A10/A4 are don't care, except for address bit A7 which
must be “0”. Least significant address bits A3/A0 define the byte location inside the
Identification page.
If the Identification page is locked, the data bytes transferred during the Write Identification
Page instruction are not acknowledged (NoAck).
Lock Identification Page
The Lock Identification Page instruction (Lock ID) permanently locks the Identification page
in Read-only mode. The Lock ID instruction is similar to Byte Write (into memory array) with
the following specific conditions:
• Device type identifier = 1011b
• Address bit A7 must be ‘1’; all other address bits are don't care
• The data byte must be equal to the binary value xxxx xx1x, where x is don't care
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