m28w640fcb STMicroelectronics, m28w640fcb Datasheet - Page 71

• Manufacturer Part Number: m28w640fcb
• Description: 64 Mbit 4mb X16, Boot Block 3v Supply Flash Memory
• Manufacturer: STMicroelectronics

M28W640FCT, M28W640FCB
Figure 23. Protection Register Program flowchart and pseudo code
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.
or after 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
Invalid) and b4 (Program Error) can be made after each program operation
protection_register_program_command (addressToProgram, dataToProgram) {:
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*/
Flowcharts and pseudo codes
AI04381
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