M58WR064HT datasheet(23/111 Pages) NUMONYX

23 / 111 page

M58WR064HT, M58WR064HB

Command interface - Standard commands

23/111

5.13

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.

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

command. Table 15 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:

Locking Operations Flowchart and Pseudo Code, for a flowchart for using the Unlock

command.

5.14

Block Lock-Down Command

A locked or unlocked block can be locked-down by issuing the Block Lock-Down command.

A locked-down block cannot be programmed or erased, or have its protection status

changed when WP is low, VIL. When WP is high, VIH, the Lock-Down function is disabled

and the locked blocks can be individually unlocked by the Block Unlock command.

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

●

The first bus cycle sets up the Block Lock command.

●

The second Bus Write cycle latches the block address.

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

command. Locked-Down blocks revert to the locked (and not locked-down) state when the

device is reset on power-down. Table 15 shows the Lock Status after issuing a Block Lock-

Down command. Refer to the section, Block Locking, for a detailed explanation and

Appendix C, Figure 25: Locking Operations Flowchart and Pseudo Code, for a flowchart for

using the Lock-Down command.

M58WR064HT bảng dữ liệu(PDF) 23 Page - Numonyx B.V