
R8C/3GM Group
12. ID Code Areas
R01UH0284EJ0100 Rev.1.00
Aug 09, 2011
12.3
Forced Erase Function
This function is used in standard serial I/O mode. When the ID codes sent from the serial programmer or the on-
chip debugging emulator are “ALeRASE” in ASCII code, the content of the user ROM area will be erased at once.
However, if the contents of the ID code addresses are set to other than “ALeRASE” (other than Table 12.1 ID Code Reserved Word) when the ROMCR bit in the OFS register is set to 1 and the ROMCP1 bit is set to 0 (ROM
code protect enabled), forced erasure is not executed and the ID codes are checked with the ID code check function.
Also, when the contents of the ID code addresses are set to “ALeRASE” in ASCII code, if the ID codes sent from
the serial programmer or the on-chip debugging emulator are “ALeRASE”, the content of the user ROM area will
be erased. If the ID codes sent from the serial programmer are other than “ALeRASE”, the ID codes do not match
and no command is acknowledged, thus the user ROM area remains protected.
Note:
12.4
Standard Serial I/O Mode Disabled Function
This function is used in standard serial I/O mode. When the I/D codes in the ID code storage addresses are set to the
communication with the serial programmer or the on-chip debugging emulator is not performed. This does not
allow the flash memory to be read, rewritten, or erased using the serial programmer or the on-chip debugging
emulator.
Also, if the ID codes are also set to the reserved character sequence of the ASCII codes “Protect” when the
ROMCR bit in the OFS register is set to 1 and the ROMCP1 bit is set to 0 (ROM code protect enabled), ROM code
protection cannot be disabled using the serial programmer or the on-chip debugging emulator. This prevents the
flash memory from being read, rewritten, or erased using the serial programmer, the on-chip debugging emulator,
or parallel programmer.
Table 12.2
Conditions and Operations of Forced Erase Function
Condition
Operation
ID code from serial
programmer or the
on-chip debugging
emulator
ID code in
ID code storage
address
Bits ROMCP1 and
ROMCR in OFS register
ALeRASE
–
All erasure of user ROM
area (forced erase function)
Other than ALeRASE
(1) Other than 01b
(ROM code protect disabled)
01b
(ROM code protect enabled)
ID code check
(ID code check function)
Other than ALeRASE
ALeRASE
–
ID code check
(ID code check function.
No ID code match.)
ID code check
(ID code check function)