Epson S1C6S3N2, Technical Manual

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S1C6S3N2 TECHNICAL HARDWARE
EPSON
I-61
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Clock Timer)
Clock Timer
The S1C6S3N2 Series has a built-in clock timer as the
source oscillator for OSC1 (crystal oscillator). The clock
timer is configured of a seven-bit binary counter that serves
as the input clock, a 256 kHz signal output by the prescaler.
Data of the four high-order bits (16 Hz–2 Hz) can be read
out by the software.
Figure 4.8.1 is the block diagram for the clock timer.
4.8
Configuration of
clock timer
128 Hz–32 Hz
Data bus
32 Hz, 8 Hz, 2 Hz
256 Hz
Clock timer reset signal
OSC1
oscillation
circuit
Interrupt request
Interrupt
control
16 Hz–2 Hz
Fig. 4.8.1
Block diagram of clock timer
Ordinarily, this clock timer is used for all types of timing
functions such as clocks.