Data Polling Flag (Dq7) - Fujitsu MB90390 Series Hardware Manual

28.6.1

Data Polling Flag (DQ7)

The data polling flag (DQ7) uses the data polling function to post that the automatic
algorithm is being executed or has terminated
■ Data Polling Flag (DQ7)
Table 28.6-3 lists the data polling flag state transitions (state change for normal operation) and Table 28.6-4
lists the data polling flag state transitions (state change for abnormal operation).
Table 28.6-3 Data Polling Flag State Transitions (State Change for Normal Operation)
Write →
Operating
state Completed
DQ7 →
DQ7
DATA:7
Table 28.6-4 Data Polling Flag State Transitions (State Change for Abnormal Operation)
Operating state
●
Write
Read-access during execution of the automatic write algorithm causes the flash memory to output the
opposite data of bit7 last written, regardless of the value at the address specified by the address signal.
Read-access at the end of the automatic write algorithm causes the flash memory to output bit7 of the read
value of the address specified by the address signal.
●
Chip/sector erase
For a sector erase, read-access during execution of the chip erase/sector erase algorithm causes the flash
memory to output 0 from the sector currently being erased. For a chip erase, read-access causes the flash
memory to output 0 regardless of the value at the address specified by the address signal. Read-access at
the end of the automatic write algorithm causes the flash memory to output 1 in the same way.
Chip/sector Sector
erase →
erase wait
→ Started
Completed
0 → 1
Write
DQ7 DQ7
CHAPTER 28 3M-BIT FLASH MEMORY
Sector erase
→ Erase
suspend
(sector being
erased)
0 → 1
0
Chip/sector erase
0
Sector erase
Sector erase
suspend →
suspended
Restarted
(sector not
(sector being
being erased)
erased)
1 → 0
DATA:7
567