M28R400CT, M28R400CB
Figure 18. Block Erase Flowchart and Pseudo Code
Start
erase_command ( blockToErase ) {
writeToFlash (any_address, 0x20) ;
Write 20h
writeToFlash (blockToErase, 0xD0) ;
/* only A12-A20 are significannt */
/* Memory enters read status state after
the Erase Command */
Write Block
Address & D0h
do {
Read Status
Register
status_register=readFlash (any_address) ;
/* E or G must be toggled*/
NO
b7 = 1
YES
} while (status_register.b7== 0) ;
NO
YES
NO
NO
V
Invalid
if (status_register.b3==1) /*VPP invalid error */
error_handler ( ) ;
PP
Error (1)
b3 = 0
YES
if ( (status_register.b4==1) && (status_register.b5==1) )
/* command sequence error */
Command
Sequence Error (1)
b4, b5 = 1
NO
error_handler ( ) ;
if ( (status_register.b5==1) )
/* erase error */
b5 = 0
YES
Erase Error (1)
error_handler ( ) ;
Erase to Protected
Block Error (1)
if (status_register.b1==1) /*program to protect block error */
error_handler ( ) ;
b1 = 0
YES
End
}
AI03541b
Note: If an error is found, the Status Register must be cleared before further Program/Erase operations.
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NUMONYX [ NUMONYX B.V ]
