Programming Notes - Epson S1C6S3N2 Technical Manual

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Interrupt and HALT)

Programming notes

I-96
(1) When the interrupt mask register (EIK) is set to "0", the
interrupt factor flag (IK) of the input port cannot be set
even though the pin status of the input port has changed.
(2) The interrupt factor flags of the clock timer and stop-
watch counter (TI, SWIT) are set when the timing condi-
tion is established, even if the interrupt mask registers
(ETI, EISWIT) are set to "0".
(3) 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