Fujitsu MB96300 series Hardware Manual page 873

33.6.3 Timing Limit Exceeded Flag (DQ5)
The timing limit exceeded flag (DQ5) is used to post that execution of the automatic
algorithm has exceeded the time (internal pulse count) prescribed in the flash memory.
■ Timing limit exceeded flag (DQ5)
Table 33.6-7 Timing limit exceeded flag state transitions (state change for normal operation) and Table
33.6-8 Timing limit exceeded bit flag state transitions (state change for abnormal operation) list the state
transitions of the timing limit exceeded flag.
Table 33.6-7 Timing limit exceeded flag state transitions (state change for normal operation)
Operating Write -->
state Completed
DQ5 0 -->
DATA:5
Table 33.6-8 Timing limit exceeded bit flag state transitions (state change for abnormal
operation)
Operating state
DQ5
●
Write/chip sector erase
Read-access after write or chip/sector erase automatic algorithm activation causes the flash memory to
output 0 if the time is within the prescribed time (time required for write/erase) or to output 1 if the
prescribed time has been exceeded. Because this is done regardless of whether the automatic algorithm is
being executed or has terminated, it is possible to determine whether write/erase was successful or
unsuccessful. That is, when this flag outputs 1, writing can be determined to have been unsuccessful if the
automatic algorithm is still being executed by the data polling function or toggle bit function.
For example, writing 1 to a flash memory address where 0 has been written will cause the fail state to
occur. In this case, the flash memory will lock and execution of the automatic algorithm will not terminate.
As a result, valid data will not be output from the data polling flag (DQ7). In addition, the toggle bit flag
(DQ6) will exceed the time limit without stopping the toggle operation and the timing limit exceeded flag
(DQ5) will output 1. Note that this state does not indicate that the flash memory is faulty, but has been used
incorrectly. When this state occurs, execute the Reset command.
Chip/sector Sector erase
erase --> wait
Completed --> Started
0 --> 1 0
Write
1
Sector erase
--> Erase
suspend (sector
being erased)
0
Chip/sector
erase
1
CHAPTER 33 FLASH MEMORY
Sector erase Sector erase
suspend --> suspended
Restarted (sector (sector not being
being erased) erased)
0 DATA:5
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