Renesas 16-bit single-chip microcomputer Manual De Usuario

Rev.1.02    Jul 01, 2005    page 241 of 314
REJ09B0126-0102

M16C/6N Group (M16C/6NL, M16C/6NN)

20. Flash Memory Version

This document is under development and its contents are subject to change.

Flash Memory Control Register 0

 

Symbol

Address After 

Reset

FMR0

01B7h

00000001b

b7

b6

b5

b4

b3

b2

b1

b0

0

RY/BY Status Flag

FMR00

0 : Busy (being written or erased) 

(1)

1 : Ready

CPU Rewrite Mode 
Select Bit 

(2)

0 : Disables CPU rewrite mode
1 : Enables CPU rewrite mode

FMR01

0 : Boot ROM area is accessed
1 : User ROM area is accessed

Lock Bit Disable Select
Bit 

(3)

0: Enables lock bit
1: Disables lock bit

Flash Memory Stop 
Bit 

(4) (5)

0  Enables flash memory operation
1: Stops flash memory operation
    (placed in low power dissipation mode, 

          flash memory initialized)

User ROM Area Select
Bit 

(4)

  

(Effective in only boot mode)

FMR02

FMSTP

FMR05

Set to "0"

Reserved Bit

Program Status Flag 

(6)

FMR06

Erase Status Flag 

(6)

FMR07

0 : Terminated normally
1 : Terminated in error

0 : Terminated normally
1 : Terminated in error

RW

RW

RW

RW

RW

RO

RO

-

(b4)

RW

RO

NOTES:

1.This status includes writing or reading with the lock bit program or read lock bit status command.
2. To set this bit to "1", write "0" and then "1" in succession. Make sure no interrupts or no DMA transfers will occur 

before writing "1" after writing "0".
Write to this bit when the NMI pin is in the high state. Also, while in EW0 mode, write to this bit from a program in 
other than the flash memory.
To set this bit to "0", in a read array mode. 

3. To set this bit to "1", write "0" and then "1" in succession when the FMR01 bit = 1. Make sure no interrupts or no DMA 

transfers will occur before writing "1" after writing "0".

4. Write to this bit from a program in other than the flash memory.
5. Effective when the FMR01 bit = 1 (CPU rewrite mode). If the FMR01 bit = 0, although the FMSTP bit can be set to 

"1" by writing "1" in a program, the flash memory is neither placed in lo power dissipation state nor initialized. 

6. This bit is set to "0" by executing the clear status command.

Bit Symbol

Bit Name

Function

Flash Memory Control Register 1

Symbol

Address

After Reset

FMR1

01B5h

0X00XX0Xb

b7

b6

b5

b4

b3

b2

b1

b0

0

0

0

EW1 Mode Select Bit 

(1)

0 : EW0 mode
1 : EW1 mode

FMR11

Lock Bit Status Flag

FMR16

0 : Lock
1 : Unlock

RW

RO

Set to "0"

Reserved Bit

RW

-

(b7)

Set to "0"

Reserved Bit

RW

-

(b5-b4)

The value in this bit when read is 
indeterminate.

Reserved Bit

RO

-

(b3-b2)

The value in this bit when read is 
indeterminate.

Reserved Bit

-

(b0)

RW

RO

NOTE:

1. To set this bit to "1", write "0" and then "1" in succession when the FMR01 bit in the FMR0 register = 1. Make sure no 

interrupts or no DMA transfers will occur before writing "1" after writing "0".
Write to this bit when the NMI pin is in the high state. 
The FMR01 and FMR11 bits both are set to "0" by setting the FMR01 bit to "0".

Bit Symbol

Bit Name

Function

Figure 20.4 shows FMR0 and FMR1 registers.