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[bit3] SETIMR: Sector erase timer
Sector erase operation status
After executing the first sector erase command sequence, the operation enters sector erase wait period.
bit3 outputs "0" during this period and outputs "1" if the operation exceeds the sector erase wait period.
Data polling and toggle bits become valid after the first sector erase command sequence is executed.
When this flag is "1" while the data polling or toggle bit function is indicating that the erase algorithm is
being executed, an internally controlled erase operation has started. Any subsequent written commands
are ignored (except for the temporary erase stop code input) until the data polling or toggle bit indicates
that the erasing is completed. When this flag is "0", flash memory accepts additional sector erase code
entry. In this case, it is recommended to check the status of this flag by software before writing the
succeeding sector erase code. If this flag is "1" at the second time of status check, the additional sector
erase code may have not been accepted. When a read operation is performed during a temporary sector
erase stop operation, flash memory outputs "1" if the address indicated by the address signal belongs to
the sector that is subject to the erase operation. If not, flash memory outputs the bit3 of the read value
at the address indicated by the address signal.
[bit2] TOGGL2: Toggle bit 2
Sector erase operation status
Together with toggle bit6, this toggle bit is used to report whether flash memory is under automatic
erase operation or in temporary erase stop status. bit2 toggles when reading continuously from a sector
in erase status during automatic erase operation. When reading continuously from a sector in temporary
erase stop read mode while flash memory is in temporary erase stop status mode, bit2 toggles.
When reading addresses continuously from a sector not subject to a temporary erase stop operation
while flash memory is in temporary erase stop write mode, bit2 becomes "1". Unlike bit2, bit6 only
toggles in normal write and erase operations, or in temporary erase stop status write operation.
For example, bit2 and bit6 are used together to detect a temporary erase stop read mode (bit2 toggles
but bit6 does not). bit2 is also used to detect sectors that are subject to erase operations. When the flash
memory is in the erase operation and if data is read from a sector that is subject to an erase operation,
bit2 toggles.
CHAPTER 17 FLASH MEMORY
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