Chip Erase; Sector Erase - Fujitsu F2MC-16LX MB90580 Series Hardware Manual

C.6 Details of Flash Memory Programming/Erasing
C.6.3 Chip Erase
This section will describe how to issue the chip erase command to erase the whole chip.
To erase all data from the flash memory, the chip erase command found in command sequence table
(refer to Section C.4, Automatic Algorithm Initiation Method, Table C.4a) can be used and needs to be
send continuously to the target address in the flash memory.
Chip erase command is executed by six bus write cycles. Chip erase operation will start after 6th bus write
cycle is finished. It is no necessary for the user to program the flash memory before erasing the chip.
During Automatic Erase Algorithm execution, flash Memory will automatically write "0" to all bits before
chip erase is operated.
C.6.4 Sector Erase
This section will describe how to issue the sector erase command to erase any sector in the flash memory.
Single sector or multiple sector can be erased in the same time.
To erase a sector in the flash Memory, the sector erase command found in command sequence table
(refer to Section C.4, Automatic Algorithm Initiation Method, Table C.4a) can be used and needs to be sent
continuously to the target sector in the flash memory.
• Specifying sector
Sector erase command is executed by six bus write cycles. 50 µS of sector erase wait time will be
started after issuing sector erase code (30H) to the accessible even numbered address of the sector in
the 6th bus write cycle. When erasing several sectors in the same time, the erase code (30H) to the
address of sectors to be erased needs to be issued.
• Precautions on Specifying Multiple Sectors
Sector erase operation will be started when the 50 µS of sector erase wait time is completed after the
last sector erase code is issued. When erasing several sectors, it is necessary to input the address and
the erase code of the following sector to erase in the 50 µS of sector erase wait time. However, the
sector erase operation may not be accepted even after this wait time. It is necessary to check the sec-
tor erase timer flag (DQ3) to ensure whether the sector erase code issued was valid. At this time, the
address to read the sector erase timer flag (DQ3) should be specified to the sector to be erased.
• Sector Erase Procedure
By checking hardware sequence flag, the status of Automatic Algorithm in flash memory can be
determined (refer to 1.5 Automatic algorithm execution status). Figure C.6.4a shows the example
procedure of sector erase in the Flash Memory. In this example procedure, the toggle bit flag (DQ6) is
used to check erase completion Take note that the data read for DQ6 is the data in the sector that will
be erased. It is not necessary to check the data polling flag (DQ7) even if the exceeded timing limits
flag (DQ5) is "1". It is because data polling flag (DQ7) will change at the same time the exceed timing
limits flag (DQ5) is changed. Furthermore, it is necessary to re-check the toggle bit flag (DQ6) since it
will stop at the same time exceeded timing limits flag (DQ5) changes to "1".
370 Appendix C: The Flash Memory in the MB90F583 MB90580 Series