M95040-DF datasheet(28/46 Pages) STMICROELECTRONICS

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Instructions

M950x0-W M950x0-R M950x0-DF

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DocID6512 Rev 13

6.10

Lock Identification Page (available only in M95040-D device)

The Lock Identification Page (LID) command is used to permanently lock the Identification

Page in Read-only mode.

The LID instruction is issued by driving Chip Select (S) low, sending (MSB first) the

instruction code, the address and a data byte on Serial Data input (D), and driving Chip

Select (S) high. In the address sent, A7 must be equal to 1. All other address bits are Don't

Care (it might be easier to define these bits as 0, as shown in Table 5). The data byte sent

must be equal to the binary value xxxx xx1x, where x = Don't Care. The LID instruction is

terminated by driving Chip Select (S) high at a data byte boundary, otherwise, the instruction

is not executed.

Figure 17. Lock ID sequence

Driving Chip Select (S) high at a byte boundary of the input data triggers the self-timed Write

cycle which duration is tW (specified in Section 9: DC and AC parameters). The instruction

sequence is shown in Figure 17.

The instruction is discarded, and is not executed if the Block Protect bits (BP1,BP0) = (1,1)

or one of the conditions defined in Section 4.3: Data protection and protocol control is not

satisfied.

M95040-DF Datasheet(PDF) 28 Page - STMicroelectronics