M28W800CB datasheet(45/49 Pages) STMICROELECTRONICS

Part #	M28W800CB

Description	8 Mbit 512Kb x16, Boot Block 3V Supply Flash Memory

PDF	49 Pages

Scroll/Zoom	100%

Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

Logo

45 / 49 page

45/49

M28W800CT, M28W800CB

Figure 22. Locking Operations Flowchart and Pseudo Code

Write

01h, D0h or 2Fh

AI04364

Read Block

Lock States

YES

Locking

change

confirmed?

Start

Write 60h

locking_operation_command (address, lock_operation) {

writeToFlash (any_address, 0x60) ; /*configuration setup*/

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*/

}

Write FFh

Write 90h

End

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) ;

M28W800CB Datasheet(PDF) 45 Page - STMicroelectronics