Renesas M16C/29 Series Hardware Manual page 438

M16C/29 Group
1.4 Precautions for Protect
Set the PRC2 bit to "1" (write enabled) and then write to any address, and the PRC2 bit will be cleared to "0"
(write protected). The registers protected by the PRC2 bit should be changed in the next instruction after
setting the PRC2 bit to "1". Make sure no interrupts or DMA transfers will occur between the instruction in
which the PRC2 bit is set to "1" and the next instruction.
Rev.1.00 Nov 01,2004
REJXXXXXXX-0100Z
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