R28 datasheet(377/473 Pages) RENESAS

377 / 473 page

R8C/28 Group, R8C/29 Group

19. Flash Memory

Rev.2.10

Sep 26, 2008

Page 358 of 441

REJ09B0279-0210

19.4.3.5

Block Erase

When 20h is written in the first bus cycle and D0h is written to a given address of a block in the second bus

cycle, an auto-erase operation (erase and verify) of the specified block starts.

The FMR00 bit in the FMR0 register can be used to determine whether auto-erasure has completed.

The FMR00 bit is set to 0 during auto-erasure and set to 1 when auto-erasure completes.

The FMR07 bit in the FMR0 register can be used to determine the result of auto-erasure after auto-erasure has

completed (refer to 19.4.5 Full Status Check).

When the FMR02 bit in the FMR0 register is set to 0 (rewriting disabled) or the FMR02 bit is set to 1 (rewriting

enabled) and the FMR15 bit in the FMR1 register is set to 1 (rewriting disabled), the block erase commands

targeting block 0 are not acknowledged. When the FMR16 bit is set to 1 (rewriting disabled), the block erase

commands targeting block 1 are not acknowledged.

Do not use the block erase command during program-suspend.

Figure 19.14 shows the Block Erase Command (When Erase-Suspend Function Disabled). Figure 19.15 shows

the Block Erase Command (When Erase-Suspend Function Enabled).

In EW1 mode, do not execute this command for any address to which a rewrite control program is allocated.

In EW0 mode, the MCU enters read status register mode at the same time auto-erasure starts and the status

1 when auto-erasure completes. In this case, the MCU remains in read status register mode until the next read

array command is written.

Figure 19.14

Block Erase Command (When Erase-Suspend Function Disabled)

Start

Write the command code 20h

Write D0h to a given block

address

FMR00 = 1?

Full status check

Block erase completed

Yes

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