r5f21368sdfp Renesas Electronics Corporation., r5f21368sdfp Datasheet - Page 664

• Manufacturer Part Number: r5f21368sdfp
• Description: Renesas Mcu R8c Family / R8c/3xt-a Series
• Manufacturer: Renesas Electronics Corporation.

Under development
R8C/36T-A Group
R01UH0240EJ0001 Rev.0.01
Apr 28, 2011
26.4
26.4.1
26.4.2
Standard serial I/O mode has an ID code check function, and parallel I/O mode has a ROM code protect function to
prevent the flash memory from being read or rewritten easily.
The ID code check function is used in standard serial I/O mode. Unless 3 bytes (addresses 0FFFCh to 0FFFEh)
of the reset vector are set to FFFFFFh, the ID codes sent from the serial programmer or the on-chip debugging
emulator and the 7-byte ID codes written in the flash memory are checked to see if they match. If the ID codes
do not match, the commands sent from the serial programmer or the on-chip debugging emulator are not
accepted. Refer to 5.3 ID Code Area for details on the ID code check function.
The ROM protect function prevents the contents of the flash memory from being read, rewritten, or erased
using the OFS register in parallel I/O mode.
Refer to 5.5 Option Function Select Area for details on the option function select area.
The ROM code protect function is enabled by writing 1 to the ROMCR bit and writing 0 to the ROMCP1 bit.
This prevents the contents of the on-chip flash memory from being read or rewritten.
Once ROM code protection is enabled, the contents of the internal flash memory cannot be rewritten in parallel
I/O mode. To disable ROM code protection, erase the block including the OFS register using CPU rewrite mode
or standard serial I/O mode.
Functions to Prevent Flash Memory from being Rewritten
ID Code Check Function
ROM Code Protect Function
Preliminary document
Specifications in this document are tentative and subject to change.
26. Flash Memory
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