Fujitsu MB89202 Computer Hardware User Manual


 
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CHAPTER 17 FLASH MEMORY
17.4.3 Timing Limit Exceeded Flag (DQ5)
The timing limit exceeded flag is used to post that execution of the automatic algorithm
has exceeded the time (internal pulse count) prescribed in the flash memory.
Automatic Write/Erase
Bit5 indicates that execution of the automatic algorithm exceeded the time (internal pulse count) specified
in flash memory. For an excess, bit5 outputs 1. Thus, if this bit outputs 1 while the automatic algorithm is
operating, data writing or data erasing failed.
Bit5 indicates a failure when an attempt is made to write data into a non-blank area without erasing any
data. In the case of such a failure, fixed data cannot be read from bit7 (data polling) and bit6 (toggle bit)
remains unchanged (toggled). If the time limit is exceeded while there is a failure, "1" is set in bit5. In this
case, note that the setting of bit5 to "1" does not indicate a flash memory failure but the incorrect use of
flash memory. If bit5 is set to "1" as described above, execute a reset command.