Omron FQM1-MMA21 7-4Interval Timer Interrupts, 7-4-1, Applicable Models, 7-4-2, Overview, 7-4-3

Interval Timer Interrupts Section 7-4

The following timing chart shows the operation of the program as it is exe- cuted.

CIO 0000.00

Interrupt task 000

CIO 0000.01

Interrupt task 001

10 counts 10 counts 20 counts

(See note 1.) (See note 1.)

CIO 0002.00

(See note 2.)

	Note	(1) Counting continues even while the interrupt task is being executed.
		(2) The input interrupts are masked after this point.
7-4 Interval Timer Interrupts
7-4-1	Applicable Models
		Model number	Functions
		FQM1-CM001	Coordinator Module
		FQM1-MMP21	Motion Control Module for Pulse I/O
		FQM1-MMA21	Motion Control Module for Analog I/O
7-4-2	Overview
		Interval timers can be used to perform high-speed, high-precision timer inter-
		rupt processing. The Motion Control Modules and Coordinator Module are
		equipped with one interval timer each.
7-4-3	Interval Timer Interrupt Modes

There are two modes for interval timer operation.

•One-shot Mode

In one-shot mode, the interrupt is executed just once when the timer times out.

•Scheduled Interrupt Mode

In scheduled interrupt mode, the timer is reset to the SV each time it times out so the interrupt is repeated regularly at a fixed interval.

7-4-4 Using Interval Timer Interrupts

1,2,3... 1. Interrupt Mode

•Determine whether the timer will operate in one-shot mode or scheduled interrupt mode.

2.Ladder Programming

•Use the STIM(980) instruction to set the timer SV and start the timer in one-shot or scheduled interrupt mode.

•Create the interrupt task program.

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