R8C/13 Group
17.4 CPU Rewrite Mode
• Block Erase
Write ‘2016’ in the first bus cycle and write ‘D016’ to the given address of a block in the second 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.
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 17.4.5, “Full Status Check.”)
When the FMR02 bit in the FMR0 register is set to “0” (rewrite disabled) or the FMR02 bit is set to “1”
(rewrite enabled) and the FMR15 bit in the FMR1 register is set to “1” (rewrite disabled), the block
erase command on the Block 0 is not accepted. When the FMR16 bit is set to “1” (rewrite disabled),
the block erase command on the Block 1 is not accepted.
Figure 17.10 shows an example of a block erase flowchart when the erase-suspend function is not
used. Figure 17.11 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.
Start
Write the command code ‘2016
’
Write ‘D016’ to the given block
address
NO
FMR00=1?
YES
Full status check
Block erase completed
Figure 17.10 Block Erase Command (When Not Using Erase-suspend Function)
Rev.1.20 Jan 27, 2006 page 177 of 205
REJ09B0111-0120
RENESAS [ RENESAS TECHNOLOGY CORP ]
