Suspending Sector Erasure For The Flash Memory - Fujitsu MB90480 Series Hardware Manual

23.6.5 Suspending Sector Erasure for the Flash Memory

This section describes the procedure for issuing the sector erase suspend command
to suspend a sector erase operation for the flash memory. During erase suspension,
data can be read from any sector that is not subject to erasure.
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Suspending sector erasure for the flash memory
To suspend sector erasure for the flash memory, send the sector erase suspend command in
the command sequence table (see Table 23.4-1) from CPU to the internal flash memory.
The sector erase suspend command is used to suspend the erasure during a sector erase
operation, allowing data from a sector that is not being erased to be read. In this state, only
reading is allowed; writing is prohibited. This command is enabled only in sector erase mode,
including within the erase wait time, and ignored in chip erase mode or during write operations.
This operation is executed by writing the erase suspend code (B0
arbitrary address in flash memory. During the erase suspend state, repeatedly issued erase
suspend commands are ignored.
If a sector erase suspend command is entered during the sector erase wait time, sector erase
wait ends immediately, the erase operation is interrupted, and the operational state changes to
erase stop.
If a erase suspend command is entered during a sector erase operation after the sector erase
wait time, the system enters the erase suspend mode after 20 μs have elapsed or earlier.
Please execute the sector erase stop command after sector erase command or sector erase
resume command issuing and 20 μs or more.
CHAPTER 23 2M/3M BIT FLASH MEMORY
). To do so, specify an
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