Erasing Any Data In Flash Memory (Sector Erasing) - Fujitsu F2MC-16LX Hardware Manual

CHAPTER 25 3M-BIT FLASH MEMORY
25.6.4

Erasing Any Data in Flash Memory (Sector Erasing)

The procedure to issue the sector erase command and erase any data in the flash
memory is described. Sector-by-sector erasing is enabled and multiple sectors can be
specified at a time.
Erasing Any Data in Flash Memory (Sector Erasing)
To erase any data in the flash memory, you may send the sector erase command sequentially in the
command sequence table (See Table 25.4-1) to the target sector in the flash memory.
How to specify sector
The sector erase command is executed in six bus operations. In the sixth cycle, the 50 µs sector erase wait
is started by writing the sector erase code (30
erase multiple sectors, write the erase code (30
following the above procedure.
Notes on specifying multiple sectors
Sector erasing is started after a 50 µs period waiting for sector erasing is completed after the last sector
erase code has been programmed. In other words, when multiple sectors are erased at the same time, the
next erase sector address and the erase code (in the command sequence sixth cycle) need to be entered
within 50 µs, after which they may not be accepted. You may check if writing the subsequent sector erase
code is enabled or not by the sector erase timer (hardware sequence flag: DQ3). In this case, make sure that
the address to read the sector erase timer indicates the sector to be erased.
Procedure of Sector Deletion
You may determine the state of the automatic algorithm in the flash memory by using the hardware
sequence flag (See "25.5 Check the Execution State of Automatic Algorithm"). Figure 25.6-2 shows an
example of the sector erase procedure of the flash memory. In this example, the toggle bit flag (DQ6) is
used to check that erase ends.
Please note that data to be read for flag check is read from the sector to be erased.
The toggle bit flag (DQ6) terminates the toggle operation at the moment at which the timing limit excess
flag (DQ5) changes into "1", you need to recheck the toggle bit flag (DQ6) even if the timing limit excess
flag (DQ5) is "1".
Likewise, the data polling flag (DQ7) changes at the moment at which the timing limit excess flag (DQ5)
changes into "1", you need to recheck the data polling flag (DQ7).
582
) into any even one address accessible in the target sector. To
H
) into the address in the target sector to be erased,
H