Toggle Bit Flag (Dq6) - Fujitsu MB90460 Series Hardware Manual

23.5.2

Toggle Bit Flag (DQ6)

The toggle bit flag specifies whether the automatic algorithm is being executed or has
been terminated, using the toggle bit function, the same as the data polling flag. Table
23.5-4 shows the toggle bit flag status transition.
■ When the Write Operation or Chip/Sector Deletion Operation is Executed.
When the continuous read/access is executed during the automatic write algorithm or chip/sector deletion
algorithm execution, the flash memory outputs the toggle status, in which "1" and "0" are alternately output
for each read operation, irrespective of the specified address. If the continuous read/access is executed at
the end of the automatic write algorithm or chip/sector deletion algorithm, the flash memory stops the
toggle operation in bit6 and outputs the data of bit6 (DATA:6) in the specified read address.
■ When the Sector Deletion Temporary Stop 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. The flash memory outputs the data
of bit6 (DATA:6) in the specified read address unless the specified address belongs to the sector being
deleted.
Reference:
When executing the write operation, the toggle bit executes the toggle operation for about 2 ms, then
terminates it without rewriting the data, if the sector to be written is write-protected.
When executing the deletion operation, the toggle bit executes the toggle operation for about 100
ms, then returns to the read/reset status without rewriting the data, if all the selected sectors are
protected from rewriting.
Toggle Bit Flag Status Transition
Table 23.5-4 Toggle Bit Flag Status Transition
- Status transition during normal operation
Operating Write operation
status --> Completion
Toggle
DQ6
-->DATA:6
- Status transition during abnormal operation
Operating status Write operation
DQ6 Toggle
Chip/sector
Sector deletion
deletion
wait-->Start
-->Completion
Toggle-->Stop
Toggle
Chip/sector deletion operation
Toggle
CHAPTER 23 512K / 1024K BIT FLASH MEMORY
Sector deletion
Sector deletion
-->Deletion
temporary stop
temporary stop -->Restart
(Sector being (Sector being
deleted) deleted)
1-->Toggle
Toggle-->1
During the sector
deletion temporary
stop (Sector not
being deleted)
DATA:6
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