Programming Notes - Epson S1C6S3N2 Technical Manual

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Stopwatch Counter)

Programming notes

I-72
(1) If counter data is read out in the RUN status, the counter
must be made into the STOP status, and after data is
read out the RUN status can be restored. If data is read
out when a carry occurs, the data cannot be read cor-
rectly.
Also, the processing above must be performed within the
STOP interval of 976 µs (256 Hz 1/4 cycle).
(2) 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.
EPSON
S1C6S3N2 TECHNICAL HARDWARE