Fujitsu 8FX User Manual

MB95630H Series
MN702-00009-2v0-E FUJITSU SEMICONDUCTOR LIMITED 543
CHAPTER 26 DUAL OPERATION FLASH MEMORY
26.4 Checking Automatic Algorithm
Execution Status
26.4.1 Data Polling Flag (DQ7)
The data polling flag (DQ7) is a hardware sequence flag indicating that the
automatic algorithm is being executing or has been completed using the data
polling function.
■ Data Polling Flag (DQ7)
Table 26.4-3 and Table 26.4-4 show the state transition of the data polling flag during normal
operation and the one during abnormal operation respectively.
● At programming
When read access takes place during execution of the automatic write algorithm, the Flash
memory outputs the inverted value of bit7 in the last data written to DQ7.
If read access takes place on completion of the automatic write algorithm, the Flash memory
outputs bit7 of the value read from the read-accessed address to DQ7.
● At chip/sector erase
When read access is made to the sector currently being erased during execution of the chip/
sector erase algorithm, bit7 of Flash memory outputs "0". Bit7 of Flash memory outputs "1"
upon completion of chip/sector erase.
● At sector erase suspension
• When read access takes place with a sector erase operation suspended, the Flash memory
outputs "0" to DQ7 if the read address is the sector being erased. If not, the Flash memory
outputs bit7 (DATA:7) of the value read from the read address to DQ7.
• Referring the data polling flag (DQ7) together with the toggle bit flag (DQ6) permits a
decision on whether Flash memory is in the sector erase suspended state or which sector is
being erased.
Table 26.4-3 State Transition of Data Polling Flag (During Normal Operation)
Operating
state
Programming →
Programming
completed
Chip/sector
erase →
Erasing
completed
Sector erase
wait →
Erasing started
Sector erase →
Sector erase
suspended
(Sector being
erased)
Sector erase
suspended →
Erasing resumed
(Sector being
erased)
Sector erase
being suspended
(Sector not being
erased)
DQ7 DQ7
→ DATA: 7 0 → 1 0 0 0 DATA: 7
Table 26.4-4 State Transition of Data Polling Flag (During Abnormal Operation)
Operating state Programming Chip/sector erase
DQ7 DQ7
0

Fujitsu 8FX Specifications

General

Brand	Fujitsu
Model	8FX
Category	Computer Hardware
Language	English