Fujitsu MB96300 series Hardware Manual page 872

CHAPTER 33 FLASH MEMORY
33.6.2 Toggle Bit Flag (DQ6)
Like the data polling flag, the toggle bit flag (DQ6) uses the toggle bit function to post
that the automatic algorithm is being executed or has terminated.
■ Toggle bit flag (DQ6)
Table 33.6-5 Toggle bit flag state transitions (state change for normal operation) and Table 33.6-6 Toggle
bit flag state transitions (state change for abnormal operation) list the state transitions of the toggle bit flag.
Table 33.6-5 Toggle bit flag state transitions (state change for normal operation)
Operating Write -->
state Completed
Toggle -->
DQ6
DATA:6
Table 33.6-6 Toggle bit flag state transitions (state change for abnormal operation)
Operating state
DQ6
●
Write/chip sector erase
Successive read-access during execution of the automatic write algorithm and chip/sector erase algorithm
causes the flash memory to toggle the DQ6 flag for every read cycle, regardless of the value at the address
specified by the address signal. Continuous read-access at the end of the automatic write algorithm and
chip/sector erase algorithm causes the flash memory to stop toggling bit 6 and output bit 6 (DATA: 6) of
the read value of the address specified by the address signal.
●
Sector erase suspend
Read-access during a sector erase suspend causes the flash memory to output DQ6 = 1 if the address
specified by the address signal belongs to the sector being erased. The flash memory outputs bit 6 (DATA:
6) of the read value at the address specified by the address signal if the address specified by the address
signal does not belong to the sector being erased.
Note:
For a write, if the sector where data is to be written is rewrite-protected, the toggle bit terminates the
toggle operation after approximately 2µs without any data being rewritten. For an erase, if all of the
selected sectors are write-protected, the toggle bit performs toggling for approximately 100µs and then
returns to the read/reset state without any data being rewritten.
864
Chip/sector Sector erase
erase --> wait
Completed --> Started
Toggle -->
Toggle
Stop
Write
Toggle
Sector erase
--> Erase
suspend (sector
being erased)
Toggle --> 1
Chip/sector
erase
Toggle
Sector erase Sector erase
suspend --> suspended
Restarted (sector (sector not being
being erased) erased)
1 --> Toggle DATA:6