R01UH0092EJ0110 Rev.1.10
Page 111 of 807
Jul 31, 2012
M16C/64C Group
9. Power Control
9.2.1
Flash Memory Control Register 0 (FMR0)
FMR01 (CPU rewrite mode select bit) (b1)
Commands can be accepted by setting the FMR01 bit to 1 (CPU rewrite mode enabled).
To set the FMR01 bit to 1, write 0 and then 1 in succession. Do not generate any interrupts or DMA
transfers between setting 0 and 1.
Change the FMR01 bit when the PM24 bit in the PM2 register is 0 (
NMI
interrupt disabled) or high is
input to the
NMI
pin.
While in EW0 mode, write to this bit from a program in an area other than flash memory.
Enter read array mode, and then set this bit to 0.
FMSTP (Flash memory stop bit) (b3)
The FMSTP bit resets the flash memory control circuits and minimizes current consumption in the flash
memory. Access to the internal flash memory is disabled when the FMSTP bit is set to 1 (flash memory
operation stopped). Set the FMSTP bit by a program located in an area other than the flash memory.
Set the FMSTP bit to 1 under the following condition:
•
A flash memory access error occurs while erasing or programming in EW0 mode (the FMR00 bit
does not revert to 1 (ready)).
b7
0
b6 b5 b4
b1
b2
b3
Symbol
FMR0
Address
0220h
Reset Value
0000 0001b (other than user boot mode)
0010 0001b (user boot mode)
b0
Function
Bit Symbol
Bit Name
RW
Flash Memory Control Register 0
RW
—
(b5)
Reserved bit
Set to 0 in other than user boot mode
Set to 1 in user boot mode
RW
—
(b4)
Reserved bit
Set to 0
RW
FMR01
CPU rewrite mode select
bit
0 : CPU rewrite mode disabled
1 : CPU rewrite mode enabled
RO
FMR00
RY/BY status flag
0 : Busy (being written or erased)
1 : Ready
Flash memory stop bit
RW
FMSTP
0 : Flash memory operation enabled
1 : Flash memory operation stopped
(low power-mode, flash memory initialized)
RW
FMR02
Lock bit disable select bit
0 : Lock bit enabled
1 : Lock bit disabled
RO
FMR07
Erase status flag
0 : Completed as expected
1 : Completed in error
RO
FMR06
Program status flag
0 : Completed as expected
1 : Completed in error
Summary of Contents for M16C Series
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