Data Erase From Flash Memory (Chip Erase) - Fujitsu MB90895 Series Hardware Manual

19.8.3

Data Erase from Flash Memory (Chip Erase)

This section explains the procedure for inputting the chip erase command to erase all
data from flash memory.
I All Data Erase from Flash Memory (Chip Erase)
• All data can be erased from flash memory by continuously transmitting the chip erase
command in the command sequence table from CPU to flash memory.
• The chip erase command is executed in six bus operations. Chip erasing is started at
completion of the sixth programming cycle.
• Before chip erasing, the user need not perform programming to flash memory. During
execution of the automatic erasing algorithm, flash memory automatically programs 0 before
erasing all cells.
I Notes on Chip Erasure
• The chip erase command is accepted only when all sectors have been write-enabled. The chip
erase command is ignored when any of the sector write-enable/protect bits in the flash memory
write control register (FWR0/1) contains "0" (write-protected or accidental write prevented
status).
• If the hardware reset is generated during erase operation, the data of flash memory is not
guaranteed.
CHAPTER 19 512 KBIT FLASH MEMORY
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