Omron CPM1 Programming Manual

45
CQM1 Interrupt Functions Section 1-5
1-5-4 Interval Timer Interrupts
High-speed, high-precision timer interrupt processing can be executed using
interval timers. The CQM1 provides three interval timers, numbered from 0 to
2.
Note 1. Interval timer 0 cannot be used when pulses are being output to Output
Units by means of the SPED(64) instruction.
2. Interval timer 2 cannot be used at the same time as the high-speed
counter.
Processing There are two modes for interval timer operation, the One-shot Mode, in
which only one interrupt will be executed when time expires, and the Sched-
uled Interrupt Mode in which the interrupt is repeated at a fixed interval.
PC Setup When using interval timer interrupts, make the following settings in the PC
Setup in PROGRAM mode before executing the program.
Input Refresh Word Settings (DM 6636 to DM 6638)
Make these settings when it is necessary to refresh inputs.
High-speed Counter Settings (DM 6642)
When using interval timer 2, check before beginning operation to be sure that
the high-speed counter (PC Setup: DM 6642) is set to the default setting
(0000: High-speed counter not used).
Operation Use the following instruction to activate and control the interval timer.
Starting Up in One-Shot Mode
Use the STIM(69) instruction to start the interval timer in the one-shot mode.
C
2
: Decrementing counter set value (4 digits BCD): 0000 to 9999
C
2
+ 1: Decrementing time interval (4 digits BCD; unit: 0.1 ms): 0005 to 0320
(0.5 ms to 32 ms)
Each time that the interval specified in word C
2
+ 1 elapses, the decrementing
counter will decrement the present value by one. When the PV reaches 0, the
designated subroutine will be called just once and the timer will stop.
The time from when the STIM(69) instruction is executed until time elapses is
calculated as follows:
(Contents of word C
2
) x (Contents of word C
2
+ 1) x 0.1 ms = (0.5 to
319,968 ms)
If a constant is set for C
2
, then the set value of the decrementing counter will
take that value and the decrementing time interval will be 10 (1 ms). (The set
value is expressed in ms.)
15 0
DM6636 to DM 6638
Bit
Number of words (2 digits BCD) 00 to 12
Beginning word no. (2 digits BCD) 00 to 11
Default: No input refresh
DM 6636: Timer 0
DM 6637: Timer 1
DM 6638: Timer 2
(@)STIM(69)
C
1
C
2
C
3
C
1
: Interval timer no.
Interval timer 0: 000
Interval timer 1: 001
Interval timer 2: 002
C
2
: Timer set value (first word address)
C
3
: Subroutine no. (4 digits BCD): 0000 to 0255

Omron CPM1 Specifications

General

Model	CPM1
Manufacturer	Omron
Instruction Set	Basic and advanced instructions
Power Supply	100 to 240 VAC or 24 VDC
Communication	RS-232C
I/O Points	10, 20, 30, or 40 points depending on the model
Timers	Yes, multiple timers available
Counters	Yes, multiple counters available
Input Voltage	24V DC
Output Type	Relay or transistor
Number of I/O Points	10, 20, 30, 40
Communication Ports	RS-232C (optional)
Operating Temperature	0°C to 55°C
Storage Temperature	-20°C
Humidity	10% to 90% (non-condensing)
Dimensions	Varies depending on the model
Weight	Varies depending on the model
Program Memory	2048 steps (2K steps)