Instructions
M95640-W M95640-R M95640-DF
6.7
Read Identification Page (available only in M95640-D
devices)
The Identification Page (32 bytes) is an additional page which can be written and (later)
permanently locked in Read-only mode.
Reading this page is achieved with the Read Identification Page instruction (see Table 4).
The Chip Select signal (S) is first driven low, the bits of the instruction byte and address
bytes are then shifted in, on Serial Data Input (D). Address bit A10 must be 0, upper
address bits are Don't Care, and the data byte pointed to by the lower address bits [A4:A0]
is shifted out on Serial Data Output (Q). If Chip Select (S) continues to be driven low, the
internal address register is automatically incremented, and the byte of data at the new
address is shifted out.
The number of bytes to read in the ID page must not exceed the page boundary, otherwise
unexpected data is read (e.g.: when reading the ID page from location 10d, the number of
bytes should be less than or equal to 22d, as the ID page boundary is 32 bytes).
The read cycle is terminated by driving Chip Select (S) high. The rising edge of the Chip
Select (S) signal can occur at any time during the cycle. The first byte addressed can be any
byte within any page.
The instruction is not accepted, and is not executed, if a write cycle is currently in progress.
Figure 14. Read Identification Page sequence
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Doc ID 16877 Rev 16
STMICROELECTRONICS [ ST ]
