M16C62_M Datasheet, PDF (319/615 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/60 SERIES

Protect
Mitsubishi microcomputers
M16C / 62A Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
2.1 Protect Usage
2.1.1 Overview of the protect usage
'Protect' is a function that causes a value held in a register to be unchanged even when a program runs
away. The following is an overview of the protect usage:
(1) Registers affected by the protect function
The registers affected by the protect function are:
(a) System clock control registers 0, 1 (addresses 000616 and 000716)
(b) Processor mode registers 0, 1 (addresses 000416 and 000516)
(c) Port P9 direction register (address 03F316), SI/Oi control register (i=3,4)(addresses 036216 and
036616)
The values in registers (1) through (3) cannot be changed in write-protect state. To change values in
the registers, put the individual registers in write-enabled state.
(2) Protect register
Figure 2.1.1 shows protect register.
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