Erasing All Data From Flash Memory (Chip Erase) - Fujitsu 8FX Hardware Manual

MB95630H Series
26.5.3

Erasing All Data from Flash Memory (Chip Erase)

This section explains the procedure for issuing the chip erase command to
erase all data in the Flash memory.
■ Erasing Data from Flash Memory (Chip Erase)
• To erase all data from the Flash memory, send the chip erase command mentioned in the
command sequence table continuously from the CPU to the Flash memory.
• The chip erase command is executed in six bus operations. Chip erasing starts at the point
when the sixth cycle of programming commands is complete.
• In chip erase, the user does not need to program data to the Flash memory before starting
erasing data. While the automatic erase algorithm is running, it automatically writes "0" to
all cells in the Flash memory before erasing data.
■ Note on Chip Erase
• The chip erase command is accepted only when programming data to all sectors has been
enabled. The chip erase command is ignored even if only one bit for a sector in the flash
memory sector write control register 0 (SWRE0) has been set to "0" (to disable
programming data to that sector).
• During chip erase, if a hardware reset occurs, the integrity of data in the Flash memory is
not guaranteed.
MN702-00009-2v0-E
CHAPTER 26 DUAL OPERATION FLASH MEMORY
FUJITSU SEMICONDUCTOR LIMITED
26.5 Programming/Erasing Flash Memory
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