Reference Oscillator - Sanyo AVM-2550S Training Manual

REFERENCE OSCILLATOR

The CPU requires a stable oscillator to serve as the clock signal. This clock
signal will be used to control the timing of all CPU functions and control
pulses. X801 connected between pins 19 and 20 of the CPU, provides a
stable, crystal controlled oscillator frequency of 8 MHz that is used for the
clock signal.
C809
X801
C808
8 MHz Reference Oscillator
REFERENCE OSCILLATOR
IC801
CPU
19
20
TIME DISPLAY FEATURE
The C-003 CPU provides a time display feature. The time of day clock is
timed by counting the reference oscillator frequency of 8 MHz served to the
CPU. The oscillator frequency is maintained accurate within ± 0.003 percent,
which provides a convenient and accurate timing signal for the clock. The
Clock and the Sleep Timer cannot be set if this timing signal is missing,
because of no signal to control the timing of all CPU functions and control
pulses.
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