Specifications

S1C6S2N7 TECHNICAL HARDWARE EPSON I-49
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Stopwatch Timer)
Stopwatch Timer
The S1C6S2N7 Series incorporates a 1/100 sec and 1/10
sec stopwatch timer. The stopwatch timer is configured as a
two-stage, four-bit BCD timer serving as the clock source for
an approximately 100 Hz signal (obtained by approximately
dividing the 256 Hz source clock from the oscillation circuit).
Data can be read out four bits at a time by the software.
When CR oscillator (typ. 65 kHz) is used as the OSC
oscillation circuit, each timer frequency becomes "CR
oscillation frequency/32,768".
In the S1C6S2A7, the stopwatch timer cannot be used.
Figure 4.8.1 is the block diagram of the stopwatch timer.
Configuration of
stopwatch timer
4.8
The stopwatch timer can be used separately from the clock
timer. In particular, digital stopwatch functions can be
easily realized by software.
SWL timer
Data bus
10 Hz, 1 Hz
256 Hz
Stopwatch timer reset signal
Stopwatch timer RUN/STOP signal
Interrupt
request
Interrupt
control
10 Hz
SWH timer
OSC
(oscillation circuit)
Fig. 4.8.1
Block diagram of
stopwatch timer