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CHAPTER 20 CLOCK MONITOR
User’s Manual U16315EJ3V1UD
372
Figure 20-3. Timing of Clock Monitor (3/4)
(5) Clock monitor status after STOP mode is released
(CLME = 1 is set when CPU clock operates on internal oscillation clock and before entering STOP mode)
Clock monitor status
Monitoring
stopped
Monitoring stopped
Monitoring
CLME
Internal oscillation clock
(CPU clock)
X1 input clock
CPU operation
Normal
operation
17 clocks
Clock supply
stopped
Normal operation
Oscillation
stopped
Oscillation stabilization time
(time set by OSTS register)
STOP
When bit 0 (CLME) of the clock monitor mode register (CLM) is set to 1 before entering STOP mode, monitoring
automatically starts at the end of the X1 input clock oscillation stabilization time. Monitoring is stopped in STOP mode
and during the oscillation stabilization time.
(6) Clock monitor status after X1 input clock oscillation is stopped by software
Clock monitor status
CLME
MSTOP or
MCCNote
Internal oscillation clock
X1 input clock
Oscillation stabilization time
(time set by OSTS register)
Normal operation (internal oscillation clock or subsystem clockNote)
Monitoring
stopped
Monitoring
CPU operation
Monitoring stopped
Oscillation
stopped
When bit 0 (CLME) of the clock monitor mode register (CLM) is set to 1 before or while oscillation of the X1 input
clock is stopped, monitoring automatically starts at the end of the X1 input clock oscillation stabilization time.
Monitoring is stopped when oscillation of the X1 input clock is stopped and during the oscillation stabilization time.
Note The register that controls oscillation of the X1 input clock differs depending on the type of the clock supplied
to the CPU.
When CPU operates on internal oscillation clock: Controlled by bit 7 (MSTOP) of the main OSC control
register (MOC)
When CPU operates on subsystem clock:
Controlled by bit 7 (MCC) of the processor clock
control register (PCC)