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CHAPTER 5 CLOCK GENERATOR
User’s Manual U19780EJ2V0UD
135
(3) Internal
oscillation mode register (RCM)
This register sets the operation mode of internal oscillator.
RCM can be set by a 1-bit or 8-bit memory manipulation instruction.
Reset signal generation sets this register to 80H
Note 1
.
Figure 5-5. Format of Internal Oscillation Mode Register (RCM)
Address: FFA0H After reset: 80H
Note 1
R/W
Note 2
Symbol
<7>
6 5 4 3 2
<1>
<0>
RCM
RSTS
0 0 0 0 0
LSRSTOP
RSTOP
RSTS
Status of internal high-speed oscillator
0
Waiting for accuracy stabilization of internal high-speed oscillator
1
Stability operating of internal high-speed oscillator
LSRSTOP
Internal low-speed oscillator oscillating/stopped
0
Internal low-speed oscillator oscillating
1
Internal
low-speed oscillator stopped
RSTOP
Internal high-speed oscillator oscillating/stopped
0
Internal
high-speed oscillator oscillating
1
Internal high-speed oscillator stopped
Notes 1.
The value of this register is 00H immediately after a reset release but automatically
changes to 80H after internal high-speed oscillator has been stabilized.
2.
Bit 7 is read-only.
Caution When setting RSTOP to 1, be sure to confirm that the CPU operates with a clock
other than the internal high-speed oscillation clock. Specifically, set under either of
the following conditions.
<1>
78K0/KB2-A
•
When MCS = 1 (when CPU operates with the high-speed system clock)
<2>
78K0/KC2-A
•
When MCS = 1 (when CPU operates with the high-speed system clock)
•
When CLS = 1 (when CPU operates with the subsystem clock)
In addition, stop peripheral hardware that is operating on the internal high-speed
oscillation clock before setting RSTOP to 1.