Omron CP1H CPU UNITS - PROGRAMMING 05-2007, Operation Manual

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101
Computing the Cycle Time
Section 2-7
(2) When using input interrupt or pulse output 2/3 and analog input/output
(XA type only), pay attention to the possibility that timer interrupt cannot
be executed within short time interval.
External Interrupt Tasks The interrupt response time for external interrupt tasks depends on the Unit or
Board (CJ-series Special I/O Unit or CJ-series CPU Bus Unit) that is request-
ing the external interrupt task of the CPU Unit and the type of service
requested by the interrupt. For details, refer to the operation manual for the
Unit or Board being used.
2-7-9 Serial PLC Link Response Performance
The response times for CPU Units connected via a Serial PLC Link (master to
slave or slave to master) can be calculated as shown below. If a PT is in the
Serial PLC Link, however, the amount of communications data will not be
fixed and the values will change.
• Maximum I/O response time (not including hardware delay) =
Master cycle time + Communications cycle time + Slave cycle time + 4 ms
• Minimum I/O response time (not including hardware delay) =
Slave communications time + 1.2 ms
Here,
2-7-10 Pulse Output Start Time
The pulse output start time is the time required from executing a pulse output
instruction until pulses are output externally. This time depends on the pulse
output instruction that is used and operation that is performed.
Software interrupt response time
Internal timer
Scheduled interrupt task
Scheduled interrupt time
Number of partici-
pating slave nodes The number of slaves to which links have been established
within the maximum unit number set in the master.
Number of non-par-
ticipating slave
nodes The number of slaves not participating in the links within the
maximum unit number set in the master
Communications
cycle time (ms) Slave communications time
×
Number of participating slave
nodes + 10
×
Number of non-participating slave nodes
Slave communica-
tions time (ms) • Communications time set to Standard
24.6 + 0.494
×
((No. of 1)
×
No. of link words
×
2 +
12)
• Communications time set to Fast
25.7 + 0.242
×
((No. of 1)
×
No. of link words
×
2 +
12)
Start time
Instruction execution
Pulse output