Renesas M16C/64A Series User Manual page 784

M16C/64A Group
32.3 Notes on Protection
After setting the PRC2 bit to 1 (write enabled), by writing to a given SFR, the PRC2 bit becomes 0 (write
disabled). Change the registers protected by the PRC2 bit in the next instruction after setting the PRC2 bit
to 1. Make sure there are no interrupts or DMA transfers between the instruction that sets the PRC2 bit to
1 and the next instruction.
R01UH0136EJ0210 Rev.2.10
Jul 31, 2012
32. Usage Notes
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