Omron SRM1 - PROGRAMING 02-2001, Руководство по программированию

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8-2 Section CPM2A/CPM2C Cycle Time and I/O Response Time
523
Code OFF execution time (
µ
s) Conditions (Top: min.; bottom: max.) ON execution
time (
µ
s)
Mnemonic
97 IORF 40.0 Refreshing IR 000 6.0
142.6 Refreshing one input word
135.4 Refreshing one output word
99 MCRO
74.0 With word-set I/O operands
5.6
116.4 With DM-set I/O operands
8-2 CPM2A/CPM2C Cycle Time and I/O Response Time
8-2-1 CPM2A/CPM2C Cycle Time
The processes involved in a single CPM2A/CPM2C cycle are shown in the fol-
lowing table, and their respective processing times are explained. Refer to the
CPM2C-S Operation Manual (W377) for information on the cyclic operation of
the CPM2C-S.
Process Content Time requirements
Overseeing Setting cycle watchdog timer, I/O bus check, UM
check, clock refreshing, refreshing bits allocated to
new functions. 0.3 ms
Program
execution User program is executed. Total time for executing instructions. (Varies
according to content of user’s program.)
Cycle time
calculation Automatic delay until minimum cycle time when a
minimum cycle time is set in DM 6619 of PC Setup.
Calculation of cycle time.
Negligible except for the delay itself when re-
quired.
I/O refreshing Output information (results of executing program) is
written to output bits.
Input information is read to input bits.
CPM2C CPU Unit: 0.06 ms
20-point CPM2A CPU Unit: 0.06 ms
30-point CPM2A CPU Unit: 0.3 ms
40-point CPM2A CPU Unit: 0.3 ms
60-point CPM2A CPU Unit: 0.54 ms
Expansion I/O Unit:
0.3 ms
RS-232C port
servicing Communications processing when a Programming
Device or Communications Adapter is connected to
the RS-232C port. 0.55 ms min., 5% or less of cycle time up to
131 ms
(The percentage of cycle time allocated to
RS-232C servicing can be set in DM 6616.)
Peripheral port
servicing Devices connected to peripheral port serviced. 0.55 ms min., 5% or less of cycle time up to
131 ms
(The percentage of cycle time allocated to pe-
ripheral port servicing can be set in DM 6617.)
Cycle Time and Operations The effects of the cycle time on CPM2A/CPM2C operations are as shown below.
When a long cycle time is affecting operation, either reduce the cycle time or im-
prove responsiveness with interrupt programs.
Cycle time Operation conditions
1 ms or longer TMHH(––) may be inaccurate when TC 000 through TC 003 or TC 008 through TC 255 are used
(operation will be normal for TC 004 through TC 007).
10 ms or longer TIMH(15) may be inaccurate when TC 004 through TC 255 are used (operation will be normal for
TC 000 through TC 003).
20 ms or longer Programming using the 0.02-second Clock Bit (SR 25401) may be inaccurate.
100 ms or longer TIM may be inaccurate. Programming using the 0.1-second Clock Bit (SR 25500) may be inaccu-
rate. A CYCLE TIME OVER error is generated (SR 25309 will turn ON).
120 ms or longer The FALS 9F monitoring time SV is exceeded. A system error (FALS 9F) is generated, and opera-
tion stops.
200 ms or longer Programming using the 0.2-second Clock Bit (SR 25501) may be inaccurate.