Omega Engineering IOP-241 - Manual (Page 29)

5.7 Interrupt Acknowledge Register (Write Only) (Base + 7)
Writing a '1' to any bit in the Interrupt Acknowledge Register will acknowledge the interrupt
generating condition which was represented in the corresponding bit of the Interrupt Status
Register. If a '1' is written to a bit in the Interrupt Acknowledge Register and the
corresponding interrupt generating condition is not present, then the appropriate bit in the
Interrupt Status Register will be reset (set to '0').
Written to acknowledge INT 7- INT0
(Bit 7 = INT7, Bit 6 = INT6,etc...) ChanCIntAck 7:0
Description Name Bit
Table 5-8. Interrupt Status Register (Write Only)
5.8 Summary of Interrupt Source Options
Two interrupt source options are provided in the IOP-241 and are summarized below:
(1) Port C Interrupt Sources
(a) The following must be programmed:
(i) Channel set for input via Data Port C Control Register.
(ii) Interrupt source enabled via Port C Interrupt Enable Register.
(iii) Mode selected via Interrupt Mode Control Register.
(b) Interrupt generated unless Interrupt Status Register is 00h:
(i) Unacknowledged interrupts are represented by a '1' in the
Interrupt Status Register.
(ii) Interrupt is generated after write of Interrupt Acknowledge Register
if any interrupts remain unacknowledged.
(c) '1' in Interrupt Status Register is reset to '0' if the following two requirements are
satisfied:
(i) Interrupt acknowledged by writing appropriate bit in Interrupt
Acknowledge Register with '1'.
(ii) Condition which caused interrupt is no longer present.
IOP-241 Users Manual 29