Specifications

I-54 EPSON S1C62N82 TECHNICAL HARDWARE
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Clock Timer)
The clock timer can interrupt on the falling edge of the 32
Hz, 8 Hz, and 2 Hz signals. The software can mask any of
these interrupt signals.
Figure 4.7.2 is the timing chart of the clock timer.
Interrupt function
As shown in Figure 4.7.2, an interrupt is generated on the
falling edge of the 32 Hz, 8 Hz, and 2 Hz frequencies. When
this happens, the corresponding interrupt event flag (IT32,
IT8, IT2) is set to 1. Masking the separate interrupts can be
done with the interrupt mask register (EIT32, EIT8, EIT2).
However, regardless of the interrupt mask register setting,
the interrupt event flags will be set to 1 on the falling edge of
their corresponding signal (e.g. the falling edge of the 2 Hz
signal sets the 2 Hz interrupt factor flag to 1).
Reading of interrupt factor flags is available at EI, but be careful in
the following cases.
If the interrupt mask register value corresponding to the interrupt
factor flags to be read is set to 1, an interrupt request will be
generated by the interrupt factor flags set timing, or an interrupt
request will not be generated.
Be very careful when interrupt factor flags are in the same address.
Clock timer timing chart Frequency
Register
bits
Address
0E4H
D0 16 Hz
D1
D2
D3
8 Hz
4 Hz
2 Hz
Occurrence of
32 Hz interrupt request
Occurrence of
8 Hz interrupt request
Occurrence of
2 Hz interrupt request
Fig. 4.7.2 Timing chart of the clock timer
Note