Renesas M16C FAMILY Hardware Manual page 170

Under development
Preliminary specification
Specifications in this manual are tentative and subject to change.
R8C/11 Group
• Block Erase
Write '20 ' in the first bus cycle and write 'D0
16
bus cycle, and an auto erase operation (erase and verify) will start.
Check the FMR00 bit in the FMR0 register to see if auto erasing has finished.
The FMR00 bit is "0" during auto erasing and set to "1" when auto erasing is completed.
When using the erase-suspend function in EW0 mode, the FMR46 bit in the FMR4 register should be
checked to see if the flash memory is placed in a erase-suspend. The FMR46 bit is set to "0" when
auto-erase operation is active and set to "0" auto-erase operation is inactive.
Check the FMR07 bit in the FMR0 register after auto erasing has finished, and the result of auto
erasing can be known. (Refer to Section 17.4.6, "Full Status Check.")
When the FMR02 bit in the FMR0 register is set to "0" (rewrite disabled), the Block Erase command
on the Block0 and Block1 is not accepted.
Figure 17.9 shows an example of a block erase flowchart when the erase-suspend function is not
used. Figure 17.10 shows an example of a block erase flowchart when the erase-suspend function is
used.
In EW1 mode, do not execute this command on any address at which the rewrite control program is
located.
In EW0 mode, the microcomputer goes to read status register mode at the same time auto erasing
starts, making it possible to read the status register. The status register bit 7 (SR7) is cleared to "0" at
the same time auto erasing starts, and set back to "1" when auto erasing finishes. In this case, the
microcomputer remains in read status register mode until the Read Array command is written next.
Figure 17.8 Block Erase Command (When Not Using Erase-suspend Function)
Rev.0.91 2003 Sep 08
Write the command code '20
Write 'D0
block address
Full status check
Block erase completed
page 160 of 184
' to the uppermost address of a block in the second
16
Start
'
16
' to the uppermost
16
NO
FMR00=1?
YES
17.4 CPU Rewrite Mode