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

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Unit Number Section 3-2
cycle make up the communications cycle, and the time required for the com-
munications cycle is known as the communications cycle time.
Network Parameters The communications cycle time is one of the network parameters. The other
network parameters are the number of polled units, maximum number of
frames, and the maximum node address. These parameters are transmitted
from the polling node to the other nodes in the network. Refer to
3-5 Network
Parameters for details on the network parameters.
Refresh Cycle Time Data is constantly being refreshed in the data link words between the SYS-
MAC LINK Unit and the CPU Unit while the data links are operating. By
refreshing data, the CPU Unit sends local node data to the SYSMAC LINK
Unit, and receives data from other nodes from the SYSMAC LINK Unit. The
interval between data refreshing is called the refresh cycle time. The refresh
cycle time can be monitored using the Support Software.
3-2 Unit Number
Up to four SYSMAC LINK Units can be mounted on a CS-series PLC and
used to connect each Unit to a different SYSMAC LINK Network. Because the
PLC incorporates bridge and gateway functions, these and other networks
can exchange data via the CPU Unit. If more than one SYSMAC LINK Unit or
other CPU Bus Unit is mounted on a single PLC, however, each Unit needs a
unit number for identification.
Setting Use the rotary switches on the front panel to set the unit number.
Setting Value Range A total of 16 SYSMAC LINK Units and/or other CPU Bus Units can be
mounted on a single PLC. Of these, up to four can be SYSMAC LINK Units.
The unit number settings range is from 0 to F Hex.
Note (1) Each Unit connected to the same PLC must have a unique number.
(2) Turn OFF the PLC when setting the rotary switches.
(3) If the unit number of any node has been changed, the I/O table on the
PLC must be generated again and that node must be turned ON after all
other nodes have been turned ON.
3-3 Setting Node Address
In token bus communications used in the SYSMAC LINK Network, the node
addresses make a logical ring around which the token is passed. The logical
ring of node addresses takes the place of the actual physical ring used in
some other networks. Consequently, proper setting of the node addresses is
essential to network operation.
Token cycle Polling cycle
Communications cycle
Token cycle Polling cycle
Communications cycle
Unit No. 6 Unit No. 12 (hexadecimal C)