r5f21346mnfp Renesas Electronics Corporation., r5f21346mnfp Datasheet - Page 206

• Manufacturer Part Number: r5f21346mnfp
• Description: Single-chip Mcus Incorporates The R8c Cpu Core
• Manufacturer: Renesas Electronics Corporation.

R8C/34M Group
R01UH0131EJ0100 Rev.1.00
Jun 21, 2011
12.3
12.4
Table 12.2
Note:
ALeRASE
Other than ALeRASE ALeRASE
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.
Table 12.2 lists the Conditions and Operations of Forced Erase 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.
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
reserved character sequence of the ASCII codes “Protect” (refer to Table 12.1 ID Code Reserved Word),
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.
ID code from serial
programmer or the
on-chip debugging
1. For “Protect”, refer to 12.4 Standard Serial I/O Mode Disabled Function .
emulator
Forced Erase Function
Standard Serial I/O Mode Disabled Function
Conditions and Operations of Forced Erase Function
ALeRASE
Other than ALeRASE
Other than ALeRASE
ID code storage
ID code in
address
Condition
(1)
(1)
–
Other than 01b
(ROM code protect disabled)
01b
(ROM code protect enabled)
–
–
ROMCR in OFS register
Bits ROMCP1 and
All erasure of user ROM
area (forced erase function)
ID code check
(ID code check function)
ID code check
(ID code check function.
No ID code match.)
ID code check
(ID code check function)
Operation
12. ID Code Areas
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