M16C6S_09 Datasheet, PDF (165/208 Pages) Renesas Technology Corp – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

M16C/6S Group
Flash Memory Version
CPU Rewrite Mode
In CPU rewrite mode, the user ROM area can be rewritten by executing software commands from the CPU.
Therefore, the user ROM area can be rewritten directly while the microcomputer is mounted on-board
without having to use a ROM programmer, etc.
Make sure the Program and the Block Erase commands are executed only on each block in the user ROM
area.
During CPU rewrite mode, the user ROM area be operated on in either Erase Write 0 (EW0) mode or Erase
Write 1 (EW1) mode. Table 1.21.1 lists the differences between Erase Write 0 (EW0) and Erase Write 1
(EW1) modes.
Table 1.21.1. EW0 Mode and EW1 Mode
Item
EW0 mode
EW1 mode
Operation mode
• Single chip mode
Single chip mode
Areas in which a
• User ROM area
User ROM area
rewrite control
program can be located
Areas in which a
Must be transferred to any area other Can be executed directly in the user
rewrite control
than the flash memory (e.g., RAM) ROM area
program can be executed before being executed
Areas which can be
User ROM area
User ROM area
rewritten
However, this does not include the area
in which a rewrite control program
exists
Software command
None
• Program, Block Erase command
limitations
Cannot be executed on any block in
which a rewrite control program exists
• Read Status Register command
Cannot be executed
Modes after Program or Read Status Register mode
Read Array mode
Erase
CPU status during Auto Operating
Hold state (I/O ports retain the state in
Write and Auto Erase
which they were before the command
was executed)^(Note)
Flash memory status • Read the FMR0 register's FMR00, Read the FMR0 register's FMR00,
detection
FMR06, and FMR07 bits in a
FMR06, and FMR07 bits in a program
program
• Execute the Read Status Register
command to read the status
register's SR7, SR5, and SR4 flags.
_______
Note: Make sure no interrupts (except NMI and watchdog timer interrupts) and DMA transfers will occur.
Rev.5.01 Dec 10, 2009 page 165 of 201
REJ03B0014-0501