M16C6N4 Datasheet, PDF (274/406 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/60 SERIES

Under development
This document is under development and its contents are subject to change.
M16C/6N Group (M16C/6N4)
21. Flash Memory Version
21.3.1 EW0 Mode
The microcomputer enters CPU rewrite mode by setting the FMR01 bit in the FMR0 register to “1” (CPU
rewrite mode enabled) and is ready to accept commands. EW0 mode is selected by setting the FMR11 bit
in the FMR1 register to “0”. To set the FMR01 bit to “1”, set to “1” after first writing “0”.
The software commands control programming and erasing. The FMR0 register or the status register
indicates whether a program or erase operation is completed as expected or not.
21.3.2 EW1 Mode
EW1 mode is selected by setting FMR11 bit to “1” (by writing “0” and then “1” in succession) after setting
the FMR01 bit to “1” (by writing “0” and then “1” in succession). (Both bits must be set to “0” first before
setting to “1”.)
The FMR0 register indicates whether or not a program or erase operation has been completed as
expected. The status register cannot be read in EW1 mode.
When an erase/program operation is initiated the CPU halts all program execution until the operation is
completed or erase-suspend is requested.
Rev.2.30 Oct 24, 2005 page 256 of 376
REJ09B0009-0230