Toggle Bit Flag (Dq6) - Fujitsu 8FX Hardware Manual

MB95630H Series
26.4.2

Toggle Bit Flag (DQ6)

The toggle bit flag (DQ6) is a hardware sequence flag using the toggle bit
function to indicate whether the automatic algorithm is being executed or has
terminated.
■ Toggle Bit Flag (DQ6)
Table 26.4-5 and Table 26.4-6 show the state transition of the toggle bit flag during normal
operation and the one during abnormal operation respectively.
Table 26.4-5 State Transition of Toggle Bit Flag (During Normal Operation)
Programming
Operating
Programming
state
completed
Toggle
DQ6
DATA: 6
Table 26.4-6 State Transition of Toggle Bit Flag (During Abnormal Operation)
Operating state
DQ6
● At programming and chip/sector erase
• When read accesses are made continuously while the automatic write algorithm or the
automatic chip/sector erase algorithm is being executed, the Flash memory toggles the
output between "1" and "0" at each read access.
• When read accesses are made continuously after the automatic write algorithm or the chip/
sector erase algorithm terminates, the Flash memory outputs bit6 (DATA:6) of the value
read from the read address at each read access.
● At sector erase suspension
When a read access is made with a sector erase operation suspended, the Flash memory outputs
"0" if the read address is the sector being erased. Otherwise, the Flash memory outputs bit6
(DATA: 6) of the value read from the read address.
Note:
When using dual-operation Flash memory (Flash memory write control program is
executed on the Flash memory), the toggle bit flag (DQ6) cannot be used to check the
operating state of programming/erasing. See the notes in "26.9 Notes on Using Dual
Operation Flash Memory" when writing a program.
The note above does not apply if the Flash memory write control program is executed on
the RAM.
MN702-00009-2v0-E
CHAPTER 26 DUAL OPERATION FLASH MEMORY
Chip/sector
Sector erase
erase
wait
Erasing
Erasing started
completed
Toggle 1 Toggle
Programming
Toggle
FUJITSU SEMICONDUCTOR LIMITED
26.4 Checking Automatic Algorithm
Sector erase Sector erase
Sector erase suspended
suspended Erasing resumed
(Sector being (Sector being
erased) erased)
Toggle 0 0 Toggle
Chip/sector erase
Toggle
Execution Status
Sector erase
being suspended
(Sector not being
erased)
DATA: 6
545