Omron CS1W-SLK11-21 - 06-2004, Руководство пользователя

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Network Parameters Section 3-5
Communications Cycle Time
This parameter sets a timer that fixes the length of the communications cycle
to the specified time. The timer operates only when the data link is in opera-
tion. Set the communications cycle time when setting the data link table’s
common link parameters.
When the timer is in operation, the communications cycle time is fixed at the
specified value, independent of the number of events that occur. Refer to
4-11
Data Link Characteristics for the formula needed to calculate the communica-
tions cycle time when the data link is set for automatic generation.
Maximum Node Address
This parameter sets the maximum node address that a node can have and
still be a part of the network. Nodes with node addresses greater than the
maximum node address will not be polled, and therefore will not participate in
network communications. This eliminates unnecessary polling of units with
node addresses above the maximum, and thus reduces the time required for
communications.
Note Set the maximum node address above the highest node address set on the
SYSMAC LINK Units currently connected unless you specifically want to
exclude one or more nodes from system operation.
Number of Polled Nodes
This parameter determines how many nodes will be polled by the polling node
during a polling cycle. Setting a high number of Units increases the communi-
cations cycle time, but reduces the time required to recognize that nodes have
been removed from or added to the network.
Maximum Number of Frames
This parameter determines how many event transmissions can take place
during a token cycle when data links are operating. With the default value of
10 frames, up to 4 event transmissions can be issued.
Event transmissions include instructions such as SEND(90), RECV(98), or
CMND(490), as well as processes such as remote monitoring and remote
programming from the Support Software.
Setting a high number of frames increases the communications cycle time,
while setting a low number will cause errors because of restrictions on event
transmissions when the data link is operating. Increase the number of frames
by three for each additional event transmission if data links are operating.
Setting Network
Parameters Network parameters are set from the Support Software. Refer to the Support
Software manual for details. Network parameters are enabled immediately
after being set.
Note (1) Do not set network parameters while data links are operating.
(2) Set the maximum node address to a value greater than the maximum
node address used in the SYSMAC LINK Units connected to the network.
Number of polled units per com-
munications cycle 4 1 to 62
Maximum number of frames per
communications cycle 10 5 to 255
Network parameter Default value Setting range