Table of Contents
Advertisement
M30245 Group
2.1 Protect
2.1.1 Overview
'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 function:
(1) Registers affected by the protect function
The registers affected by the protect function are:
(a) System clock control registers 0, 1 (addresses 0006
(b) Processor mode registers 0, 1 (addresses 0004
(c) Frequency synthesizer-related registers (address 03DB
The values in registers (a) through (c) 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.
Protect register
b7 b6 b5 b4 b3 b2 b1 b0
0
Figure 2.1.1. Protect register
Rev.2.00 Oct 16, 2006
REJ09B0340-0200
Symbol
PRCR
Bit symbol
Enables writing to system clock
PRC0
control registers 0 and 1 (addresses
0006
synthesizer registers (addresses
03DB
PRC1
Enables writing to processor mode
registers 0 and 1 (addresses 0004
and 0005
Reserved
Nothing is assigned.
When write, set "0". When read, their contents are indeterminate.
page 4 of 354
and 0007
16
and 0005
16
16
Address
When reset
000A
XXXXX000
16
Bit name
and 0007
) and frequency
16
16
to 03DF
)
16
16
)
16
)
16
)
16
to 03DF
)
16
2
Function
0 : Write-inhibited
1 : Write-enabled
0 : Write-inhibited
1 : Write-enabled
16
Must always be set to "0"
2. Protect
R
W
Advertisement
Table of Contents
