M28W320ECT Datasheet, PDF (48/53 Pages) STMicroelectronics – 32 Mbit (2Mb x16, Boot Block) 3V Supply Flash Memory

M28W320ECT, M28W320ECB
Figure 23. Locking Operations Flowchart and Pseudo Code
Start
Write 60h
Write
01h, D0h or 2Fh
Write 90h
Read Block
Lock States
Locking
NO
change
confirmed?
YES
Write FFh
End
locking_operation_command (address, lock_operation) {
writeToFlash (any_address, 0x60) ; /*configuration setup*/
if (lock_operation==LOCK) /*to protect the block*/
writeToFlash (address, 0x01) ;
else if (lock_operation==UNLOCK) /*to unprotect the block*/
writeToFlash (address, 0xD0) ;
else if (lock_operation==LOCK-DOWN) /*to lock the block*/
writeToFlash (address, 0x2F) ;
writeToFlash (any_address, 0x90) ;
if (readFlash (address) ! = locking_state_expected)
error_handler () ;
/*Check the locking state (see Read Block Signature table )*/
writeToFlash (any_address, 0xFF) ; /*Reset to Read Array mode*/
}
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