M28W640 STMicroelectronics, M28W640 Datasheet - Page 51

• Manufacturer Part Number: M28W640
• Description: 64 Mbit 4Mb x16/ Boot Block 3V Supply Flash Memory
• Manufacturer: STMicroelectronics

Figure 24. Protection Register Program Flowchart and Pseudo Code
Note: 1. Status check of b1 (Protected Block), b3 (V
2. If an error is found, the Status Register must be cleared before further Program/Erase Controller operations.
a sequence.
Write Address
Read Status
Write C0h
Register
& Data
b7 = 1
b3 = 0
b4 = 0
b1 = 0
Start
End
YES
YES
YES
YES
NO
NO
NO
NO
Program to Protected
Block Error (1, 2)
V PP Invalid
Error (1, 2)
Error (1, 2)
Program
PP
protection_register_program_command (addressToProgram, dataToProgram) {:
Invalid) and b4 (Program Error) can be made after each program operation or after
if (status_register.b3==1) /*VPP invalid error */
if (status_register.b4==1) /*program error */
if (status_register.b1==1) /*program to protect block error */
}
do {
error_handler ( ) ;
error_handler ( ) ;
error_handler ( ) ;
writeToFlash (addressToProgram, dataToProgram) ;
/*Memory enters read status state after
the Program Command*/
} while (status_register.b7== 0) ;
writeToFlash (any_address, 0xC0) ;
status_register=readFlash (any_address) ;
/* E or G must be toggled*/
M28W640CT, M28W640CB
AI04381
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