Omron CPM1 Programming Manual

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CQM1 Cycle Time and I/O Response Time Section 7-1
One cycle of CPU Unit operation is called a cycle. The time required for one
cycle is called the cycle time.
I/O Refresh Methods CQM1 I/O refresh operations are broadly divided into two categories. The first
of these, input refresh, involves reading the ON/OFF status of input points to
the input bits. The second, output refresh, involves writing the ON/OFF status
after program execution to the output points. The CQM1 I/O refresh methods
are as shown in the following table.
The initial status of the CQM1 I/O refresh is as follows:
Input: Only cyclic refresh executed.
Output: Only cyclic refresh executed.
Cyclic refresh must be executed for both inputs and outputs. If input refresh is
to be executed at the time of interrupts, then set the input refresh range in the
PC Setup (DM 6630 to DM 6638). Stopping direct refresh can be set in DM
6639 of the PC Setup.
In addition to the methods described above, it is also possible to execute I/O
refreshes in the program by means of IORF(97).
7-1-2 CQM1 Cycle Time
The processes involved in a single CQM1 cycle are shown in the following
table, and their respective processing times are explained.
Note The percentages can be changed in the PC Setup (DM 6616, DM 6617).
Input/Output I/O refresh method Function
Input Cyclic refresh Input refresh is executed at a set time once per cycle.
Interrupt input refresh Input refresh is executed before execution of the interrupt processing rou-
tine whenever an input interrupt, interval timer interrupt, or high-speed
counter interrupt occurs. (The cyclic refresh is also executed.)
Output Cyclic refresh Output refresh is executed at a set time once per cycle.
Direct refresh When there is an output from the user’s program, that output point is imme-
diately refreshed. (The cyclic refresh is also executed.)
Process Content Time requirements
Overseeing Setting cycle watchdog timer, I/O bus check, UM
check, refreshing clock, refreshing bits allocated to
new functions, etc.
0.8 ms (0.9 ms when a Memory Cassette
equipped with a clock is mounted)
Add an additional 0.1 ms for the CQM1-
CPU4@-EV1 CPU Units.
Program execution User program is executed. Total time for executing instructions.
(Varies according to content of user’s
program.)
Cycle time calculation Standby until set time, when minimum cycle time is
set in DM 6619 of PC Setup.
Calculation of cycle time.
Almost instantaneous, except for
standby processing.
I/O refresh Input Unit’s input information is read to input bits.
Output information (results of executing program)
is written to Output Unit’s output bits.
Number of input words × 0.01 ms
RS-232C port servicing Devices connected to RS-232C port serviced. 5% or less of cycle time (see note)
Peripheral port servicing Devices connected to peripheral port serviced. 5% or less of cycle time (see note)

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)