Sector Deletion Timer Flag (Dq3) - Fujitsu MB90460 Series Hardware Manual

23.5.4

Sector Deletion Timer Flag (DQ3)

After starting the sector deletion command, the sector deletion timer flag indicates
whether it is "during the sector deletion waiting period". Table 23.5-6 shows the sector
deletion timer flag status transition.
■ When the Sector Deletion Operation is Executed.
When the read/access is executed after starting the sector deletion command, the flash memory outputs "0"
if this flag indicates "during the sector deletion waiting period" irrespective of the address specified by the
address signal from the sector having issued the command. However, the flash memory outputs "1" if this
flag exceeds the defined sector deletion waiting period.
When the deletion algorithm is being executed by the data polling function or toggle bit function, the
internally-controlled deletion operation is started if this flag is "1". The succeeding sector deletion code to
be written and other commands except the sector deletion temporary stop command are ignored until
deletion is terminated.
If this flag is "0", the flash memory accepts the additional sector deletion code to be written. To verify this
event, it is recommended that this flag status be checked before writing the succeeding sector deletion code.
If this flag is "1" when the second time the status is checked, the additional sector deletion code may not be
accepted.
■ When the Sector Deletion Operation is Executed.
When the read/access is executed while executing the sector deletion temporary stop, the flash memory
outputs "1" if the specified address belongs to the sector being deleted. However, unless the specified
address belongs to the sector being deleted, the flash memory outputs the data of bit3 (DATA:3) of the
specified read address.
Sector Deletion Timer Flag Status Transition
Table 23.5-6 Sector Deletion Timer Flag Status Transition
- Status transition during normal operation
Operating
Write operation
status
--> Completion
DQ3 0-->DATA:3
- Status transition during abnormal operation
Operating status Write operation Chip/sector deletion operation
DQ3
Chip/sector
Sector deletion
deletion
wait-->Start
-->Completion
1
0-->1
0
1
CHAPTER 23 512K / 1024K BIT FLASH MEMORY
Sector deletion Sector deletion
-->Deletion temporary stop
temporary stop -->Restart
(Sector being (Sector being
deleted) deleted)
0-->1
1-->0
During the sector
deletion temporary
stop (Sector not
being deleted)
DATA:3
599