Fujitsu 8FX User Manual

MB95630H Series
MN702-00009-2v0-E FUJITSU SEMICONDUCTOR LIMITED 547
CHAPTER 26 DUAL OPERATION FLASH MEMORY
26.4 Checking Automatic Algorithm
Execution Status
26.4.4 Sector Erase Timer Flag (DQ3)
The sector erase timer flag (DQ3) is a hardware sequence flag indicating
whether the Flash memory is waiting for sector erase after the sector erase
command has started.
■ Sector Erase Timer Flag (DQ3)
Table 26.4-9 and Table 26.4-10 show the state transition of the sector erase timer flag during
normal operation and the one during abnormal operation respectively.
● At sector erase
• When a read access is made after the sector erase command has started, the sector erase
timer flag (DQ3) outputs "0" within the sector erase wait period. The flag outputs "1" if the
sector erase wait period has elapsed.
• When the data polling function or the toggle bit function indicates that the erase algorithm
is being executed (DQ7 = 0, DQ6: toggle output), the Flash memory executes sector erase.
If the command subsequently set is not a sector erase suspend command, it is ignored until
sector erase is terminated.
• If the sector erase timer flag (DQ3) is "0", the Flash memory can accept the sector erase
command. Before writing the sector erase command to the Flash memory, make sure that
the sector erase timer flag (DQ3) is "0". If the flag is "1", the Flash memory may not accept
suspending the sector erase command.
● At sector erase suspension
When a read access is made with the sector erase operation suspended, the Flash memory
outputs "1" if the read address of that read access is the address of a sector being erased. If the
read address is not the address of a sector being erased, the Flash memory outputs bit3
(DATA: 3) of the value read from the read address.
Table 26.4-9 State Transition of Sector Erase Timer 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)
DQ3 0 → DATA: 3 1 0 → 1 1 1 DATA: 3
Table 26.4-10 State Transition of Sector Erase Timer Flag (During Abnormal Operation)
Operating state Programming Chip/sector erase
DQ3 0 1

Fujitsu 8FX Specifications

General

Brand	Fujitsu
Model	8FX
Category	Computer Hardware
Language	English