M16C65 Datasheet, PDF (750/829 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M16C/60

Under development
M16C/65 Group
Preliminary Specification
This is a preliminary specification and is subject to change.
30. Flash Memory
30.8.4.5 Block Erase Command
By writing xx20h in the first bus cycle and xxD0h to the highest-order even address of a block in the
second bus cycle, an auto-erase operation (erase and verify) is started on the specified block.
The FMR00 bit in the FMR0 register indicates whether the auto-erase operation has been completed.
The FMR00 bit is set to 0 (busy) during the auto-erase operation and to 1 (ready) when the auto-
erase operation is completed.
After the auto erase operation is completed, the FMR07 bit in the FMR0 register indicates whether or
not the auto erase operation has been completed as expected. (Refer to 30.8.5.4 “Full Status
Check”).
Figure 30.4 shows a Flow Chart of the Block Erase Command Programming (Suspend Function
Disabled).
The lock bit protects individual blocks from being erased inadvertently. (Refer to 30.8.2 “Data Protect
Function”.)
In EW1 mode, do not execute this command on the block to which the rewrite control program is
allocated.
In EW0 mode, the flash memory enters read status register mode as soon as the auto-erase
operation starts. The status register can be read. The SR7 bit in the status register is set to 0 at the
same time an auto erase operation starts. It is set to 1 when the auto-erase operation is completed.
The flash memory remains in read status register mode until the read array command or read lock bit
status command is written.
If an erase error occurs, execute the clear status register command and then block erase command
at least three times until the erase error is not generated.
Start
Write the command code
xx20h ⁽¹⁾
Write xxD0h to the highest-
order block address
NO
FMR00 _Y=E1S?
YES
Full status check
Block erase operation
is completed
Notes:
1. Write the command code and data to even addresses.
Figure 30.4 Block Erase Command (Suspend Function Disabled)
REJ09B0484-0030 Rev.0.30 Sep 09, 2008
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