Omron CS1W-SLK11-21 - 06-2004, Manual

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Data Link Characteristics Section 4-11
Adding a Node to a Data Link
The number of send words for node 4 is set as 20 words in the common link
parameters, but the number of send words is set as 10 words in the common
link parameters for other nodes that are already operating. Consequently,
node 4 will not participate in the data link network.
4-11 Data Link Characteristics
4-11-1 Data Link Communications Cycle Time
Data link servicing is given priority in SYSMAC LINK Systems. The communi-
cations time for a data link can thus be maintained as a constant, regardless
of whether or not SEND(90), RECV(98), and CMND(490) are used. Fixing the
data link communications time at a constant value fixes the data link I/O
response time as well.
The communications cycle time can be set either automatically (the default) or
controlled externally.
Automatic Generation
When data link tables have been generated automatically, the communica-
tions time will be as follows for systems using coaxial cable:
The communications time will be as follows for systems using optical fiber
cable:
Node 1 Node 2 Node 3 Node 4
CIO Area
CIO Area CIO Area
CIO Area
1000
1010
1020
1030
1039
1
2
3
4
1000
1010
1020
1030
1039
1
2
3
4
1000
1010
1020
1030
1039
Startup node
Participating nodes
1000
1010
1020
1030
1049
1
2
3
4
1
2
3
4
No. of nodes Data link areas
CIO and DM Areas CIO Area only DM Area only
2 19 ms 17 ms 18 ms
4 19 ms 17 ms 18 ms
8 19 ms 18 ms 18 ms
16 19 ms 18 ms 19 ms
No. of nodes Data link areas
CIO and DM Areas CIO Area only DM Area only
2 21 ms 20 ms 21 ms
4 22 ms 20 ms 21 ms
8 22 ms 21 ms 21 ms
16 22 ms 21 ms 22 ms