M16C26A Datasheet, PDF (257/352 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/Tiny SERIES

M16C/26A Group (M16C/26A, M16C/26B, M16C/26T)
17. Flash Memory Version
17.5.2 Flash memory control register 1 (FMR1)
•FMR11 Bit
EW1 mode is entered by setting the FMR11 bit to “1” (EW1 mode). This bit is enabled only when the
FMR01 bit is “1”.
•FMR16 Bit
The combined setting of the FMR02 bit and the FMR16 bit enables to program and erase in the user
ROM area. To set this bit to “1”, it is necessary to set to “1” after first setting to “0”. Set this bit to “0” by
only writing “0”. This bit is enabled only when the FMR01 bit is “1”.
•FMR17 Bit
If FMR17 bit is “1” (with wait state), regardless of the content of the PM17 bit, 1 wait is inserted at the
access to block A and block B. Regardless of the content of the FMR17 bit, access to other block and
the internal RAM is determined by PM17 bit setting.
Set this bit to “1” (with wait state) when rewriting more than 100 times (U7 and U9).
Table 17.5.2.1. Protection using FMR16 and FMR02
FMR16
FMR02 Block A, Block B Block 0, Block 1
0
0
write enabled
write disabled
0
1
write enabled
write disabled
1
0
write enabled
write disabled
1
1
write enabled
write enabled
other user block
write disabled
write disabled
write enabled
write enabled
17.5.3 Flash memory control register 4 (FMR4)
•FMR40 Bit
The erase-suspend function is enabled by setting the FMR40 bit is set to “1” (enabled).
•FMR41 Bit
When setting the FMR41 bit to “1” in a program during auto-erasing in EW0 mode the flash module
enters erase suspend mode. In EW1 mode, the FMR41 bit is automatically set to “1” (suspend re-
quest) when an interrupt request of an enabled interrupt is generated, the FMR41 bit is automatically
set to “1” (suspend request) and when an auto-erasing operation is restarted, set the FMR41 bit to “0”
(erase restart).
•FMR46 Bit
The FMR46 bit is set to “0” during auto-erasing execution and set to “1” during erase-suspend mode.
Do not access to flash memory while this bit is “0”.
Rev. 2.00 Feb.15, 2007 page 240 of 329
REJ09B0202-0200