M95512-R datasheet(28/50 Pages) STMICROELECTRONICS

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Instructions

M95512-W M95512-R M95512-DR M95512-DF

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DocID11124 Rev 21

6.9

Read Lock Status (available only in M95512-D devices)

The Read Lock Status instruction (see Table 4) is used to check whether the Identification

Page is locked or not in Read-only mode. The Read Lock Status sequence is defined with

the Chip Select (S) 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 1, all other address bits are

Don't Care. The Lock bit is the LSB (least significant bit) of the byte read on Serial Data

Output (Q). It is at “1” when the lock is active and at “0” when the lock is not active. If Chip

Select (S) continues to be driven low, the same data byte is shifted out. The read cycle is

terminated by driving Chip Select (S) high.

The instruction sequence is shown in figure below.

Figure 17. Read Lock Status sequence

Ai15966

9 10

20 21 22 23 24 25 26 27

14 13

28 29 30

76543

High impedance

Data Out 1

Instruction

16-bit address

MSB

Data Out 2

M95512-R Datasheet(PDF) 28 Page - STMicroelectronics