Omron CS1W-CRM21 - Effects of Master Units on CPU Unit Cycle Time

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Remote I/O Communications Performance Section 5-3
• TCrmInMin: Minimum input processing time at Master Unit
Note Communications Mode 8
P = (Number of Word Input Slave Units
× 0.25 µs) + [{(Number of Bit Input
Slave Units
× 7) ÷ 8} × 0.375 µs] + [(Number of Word Output Slave Units or
Word Input Slave Units, whichever is greater) + (Number of Bit Output Slave
Units and Bit Input Slave Units, whichever is greater)
× 0.5 µs]
P Calculation Example
Conditions
P= (64 × 0.25 µs) + (16 × 0.375 µs) + ((64 + 128) × 0.5 µs) = 0.118 ms
■ Reference Example
The following table shows the calculation results for the maximum I/O
response time for a Bit Slave Unit with the minimum number of nodes and a
CPU Unit cycle time of 1 ms.
5-3-2 Effects of Master Units on CPU Unit Cycle Time
CPU Unit cycle time is affected by the number of Master Units mounted and
the communications mode that is used (e.g., the number of words allocated
for Slave Units in the I/O Memory Area when communications mode 8 is
used).
The following tables show the additional time per Master Unit on CPU Unit
cycle time for each communications mode.
CS Series
Communica-
tions mode 3
Communica-
tions mode 8
0.093 ms 0.46 ms + P
(See note.)
Baud rate Word outputs Word inputs Bit outputs Bit inputs
--- 63 nodes 64 nodes 128 nodes 127 nodes
Communications
mode
Number of nodes con-
nected
Word Slave Unit max. I/O response time (ms)
4.0 Mbit/s 3.0 Mbit/s 1.5 Mbit/s 93.75 kbit/s
Communications
mode 3
32 word nodes (16 input, 16
output)
128 bit nodes (64 bit input,
64 bit output)
4.95.05.516.2
Communications
mode 8
128 word nodes (64 input,
64 output)
256 bit nodes (128 bit input,
128 bit output)
5.75.96.626.3
Communications
mode
CPU Unit model
Communica-
tions mode 0
Communica-
tions mode 1
Communica-
tions mode 2
Communica-
tions mode 3
Communications mode 8
CS1G CPU Unit 0.244 ms 0.278 ms 0.344 ms 0.367 ms 0.180 + (0.0024 x number
of words allocated) ms
CS1G-H CPU Unit 0.189 ms 0.211 ms 0.233 ms 0.289 ms 0.135 + (0.0014 x number
of words allocated) ms
CS1H CPU Unit 0.200 ms 0.233 ms 0.300 ms 0.311 ms 0.150 + (0.0022 x number
of words allocated) ms
CS1H-H CPU Unit 0.156 ms 0.167 ms 0.200 ms 0.244 ms 0.105 + (0.0012 x number
of words allocated) ms