M58PR256J datasheet(30/114 Pages) STMICROELECTRONICS

30 / 114 page

Command interface

M58PR256J, M58PR512J

30/114

4.16

Set Configuration Register command

The Set Configuration Register command is used to write a new value to the Configuration

Two Bus Write cycles are required to issue the Set Configuration Register command.

●

The first cycle sets up the Set Configuration Register command and the address

corresponding to the Configuration Register content.

●

The second cycle writes the Configuration Register data and the confirm command.

The Configuration Register data must be written as an address during the bus write cycles,

that is A0 = CR0, A1 = CR1, …, A15 = CR15. Addresses A16-Amax are ignored.

Read operations output the array content after the Set Configuration Register command is

issued.

The Read Electronic Signature command is required to read the updated contents of the

Configuration Register.

4.17

Block Lock command

The Block Lock command is used to lock a Block and prevent program or erase operations

from changing the data in it. All Blocks are locked after power-up or reset.

Two Bus Write cycles are required to issue the Block Lock command.

●

The first bus cycle sets up the Block Lock command.

●

The second Bus Write cycle latches the Block address and locks the Block.

The lock status can be monitored for each Block using the Read Electronic Signature

command. Table 21 shows the Lock Status after issuing a Block Lock command.

Once set, the Block Lock bits remain set even after a hardware reset or power-down/power-

up. They are cleared by a Block Unlock command.

Refer to the section, Block Locking, for a detailed explanation. See Appendix C, Figure 25:

Main Array and EFA locking operations flowchart and pseudo code, for a flowchart for using

the Lock command.

4.18

Block Unlock command

The Block Unlock command is used to unlock a Block, allowing the Block to be programmed

or erased.

Two Bus Write cycles are required to issue the Block Unlock command.

●

The first bus cycle sets up the Block Unlock command.

●

The second Bus Write cycle latches the Block address and unlocks the Block.

The lock status can be monitored for each Block using the Read Electronic Signature

command. Table 21 shows the protection status after issuing a Block Unlock command.

Refer to the section, Block Locking, for a detailed explanation and Appendix C, Figure 25:

Main Array and EFA locking operations flowchart and pseudo code, for a flowchart for using

the Block Unlock command.

M58PR256J Datasheet(PDF) 30 Page - STMicroelectronics

M58PR256J Datasheet(HTML) 30 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL