User guide

5/02 Processor Only
Chapter 31
Understanding I/O Interrupts –
31–7
IID I/O Interrupt Disable – When true, this instruction clears the I/O
interrupt enable bits (S:27/1 through S:28/14) corresponding to the slots
parameter of the instruction (slots 1, 2, 7 in the following example).
Interrupt subroutines of the affected slots will not be able to execute when
an interrupt request is made. Instead, the corresponding I/O pending bits
(S:25/1 through S:26/14) will be set. The ISR will not be executed until an
IIE instruction with the same slot parameter is executed, or until the end of
the scan during which you use a programming device to set the
corresponding status file bit.
Use this instruction together with an IIE instruction to create a zone in your
main ladder program file or subroutine file in which I/O interrupts cannot
occur. The IID instruction takes effect immediately upon execution.
Setting/clearing the I/O interrupt enable bits (S:27 and S:28) with a
programming device or standard instruction such as MVM takes effect at
the END of the scan only.
Parameter – Enter a 0 (reset) in a slot position to indicate a disabled I/O
interrupt.
IIE I/O Interrupt Enable – When true, this instruction sets the I/O
interrupt enable bits (S:27/1 through S:28/14) corresponding to the slots
parameter of the instruction (slots 1, 2, 7 in the following example).
Interrupt subroutines of the affected slots will regain the ability to execute
when an interrupt request is made. If an interrupt was pending (S:25/1
through S:26/14) and the pending slot corresponds to the IIE slots
parameter, the ISR associated with that slot will execute immediately.
Use this instruction together with the IID instruction to create a zone in
your main ladder program file or subroutine file in which I/O interrupts
cannot occur. The IIE instruction takes effect immediately upon execution.
Setting/clearing the I/O interrupt enable bits (S:27 and S:28) with a
programming device or standard instruction such as MVM takes effect at
the END of the scan only.
Parameter – Enter a 1 (set) in a slot position to indicate an enabled I/O
interrupt.