![background image](http://html1.mh-extra.com/html/omron/cvm1-clk21/cvm1-clk21_operation-manual_742531217.webp)
201
Data Link I/O Response Time
Section 8-3
The equation for maximum data link I/O response time is as follows:
Note If the total number of data link words is greater than the maximum number of
words that can be exchanged per data exchange, the maximum data link I/O
response time will be cycle time of PC at node #7
×
4.
In case of the CQM1H, however, the cycle time will be incremented by the
value obtained from dividing the total number of data link words by the maxi-
mum number of words (1,200 words) per time.
For example, if the total number of data link words is 5,000, the result will be
as shown below.
5,000/1,200 = 2.5 (approx. 3)
Cycle time of PC at node #7
×
(3+3)
Noise may increase I/O delays.
Case 2
The following diagram illustrates the data flow that will produce the maximum
data link I/O response time when the cycle time of the PC at node #1
≥
the
communications cycle time and the cycle time of the PC at node #7 < the
communications cycle time.
There are three points shown in the diagram above where processing is
delayed, increasing the data link I/O response time.
Input ON delay
1.5 ms
Cycle time of PC at node #1
×
2
15 ms
×
2
Communications cycle time
×
3
9.9 ms
×
3
PC cycle time at node #7
×
3 (see note)
20 ms
×
3 (see note)
Output ON delay
15 ms
Total (data link I/O response time)
136.2 ms
Input device
Program
Program
Input
Input ON delay
1 cycle
Output
Output device
Output ON
delay
1 cycle
Communications
cycle time
Data link transmission
Controller Link Unit
transmission processing
PC at node #7
(1)
I/O refresh
Data exchange
Controller Link Unit
transmission processing
PC at node #1
Data link I/O response time
X
X
(2)
(3)
X
Содержание CVM1-CLK21
Страница 2: ......
Страница 3: ......
Страница 4: ...iv...
Страница 6: ...vi...
Страница 33: ...17 Application Precautions Section 1 5 2 9 8 2 2 8 5 2...
Страница 34: ......
Страница 42: ......
Страница 66: ......
Страница 103: ...87 Setting Data Links Section 5 2 Device Information Setting Data Link Tables...
Страница 124: ......
Страница 192: ......
Страница 280: ......
Страница 284: ......
Страница 300: ......
Страница 304: ......