Omron 3G8F7-CRM21 User Manual page 169

Remote I/O Communications Performance
C-1-3 Descriptions of Parameters
Precautions for Correct Use
T (Input Slave Unit
IN
Input Delay Time)
T (Output Slave
OUT
Unit Output Delay
Time)
T
NetCyc
(Communications
Cycle Time)
T Input Slave Unit input delay time
IN
T Output Slave Unit output delay time
OUT
T Communications cycle time
NetCyc
T Time allotted for IN frames in communications cycle time
NetIn
T Time allotted for OUT frame in communications cycle time
NetOut
T Input processing time at the Master Board
CrmIn
T Output processing time at the Master Board
CrmOut
T Processing time to release an access right
RelAcc
T Time for a PC to process the application
PC
When you calculate the parameters, do not use the actual numbers of Units
for values such as the number of Word Output Slave Units connected. Rather,
use the number of occupied nodes that is specified when the communications
cycle is started.
For details on input/output delay times for individual Slave Units, refer to
the input specifications for individual Slave Units in the CompoNet
Slave Unit Operation Manual (Cat. No. W457).
Data rate 4.0 Mbit/s
Communications 0.74 ms + G +
cycle time S1 + S2
(0.57ms + G +
S1 + S2)
The figures in parentheses are when message communications are not used.
G = (Number of Word Output Slave Units connected × additional time per
Word Output Slave Unit)
+ (Number of Word Input Slave Units × additional time per Word Input Slave Unit)
+ (Number of Bit Output Slave Units × additional time per Bit Output Slave Unit)
+ (Number of Bit Input Slave Units × additional time per Bit Input Slave Unit)
Additional Time per Unit by Slave Unit Type
Data rate
Slave Unit Type
4.06 µs
Word Output Unit
11.81 µs
Word Input Unit
0.57 µs
Bit Output Unit
10.25 µs
Bit Input Unit
G Calculation Example
3.0 Mbit/s
0.78 ms + G + 1.80 ms + G +
S1 + S2 S1 + S2
(0.57ms + G + (1.40ms + G +
S1 + S2) S1 + S2)
4.0 Mbit/s 3.0 Mbit/s
5.37 µs
22.56 µs
0.74 µs
20.64 µs
Section C-1
1.5 Mbit/s 93.75 kbit/s
23.82 ms+ G
+ S1 + S2
(16.11ms + G
+ S1 + S2)
1.5 Mbit/s 93.75 kbit/s
10.88 µs 170.93 µs
51.53 µs 657.50 µs
1.42 µs 21.25 µs
44.37 µs 531.09 µs
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