Omron CVM1-CLK21, Operation Manual

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What Are Data Links? Section 5-1
5-1 What Are Data Links?
Data links automatically exchange data in the preset areas between nodes
(PCs and/or computers) on one network. Data links can be freely created for
CS/CJ-series PCs, C200HX/HG/HE PCs, CVM1, CV-series PCs, CQM1H-
series PCs, and IBM PC/AT or compatible computers.
Two data link areas, area 1 and area 2, can be set for each node. Data links
can be set in either of the following ways.
• Data link areas can be manually set by inputting data link tables through
Controller Link Support Software. Data link tables are created to define
the data links. These tables enable free allocation of data link areas.
• Data links can be set automatically from a Programming Device. With
automatically set data links, all link areas are the same size.
Both automatic setting and manual setting cannot be used together in the
same network. The following rules apply to these two methods of setting data
links.
• Data links are enabled concurrently for area 1 and area 2.
• Separate settings (data link start words and send area size) are made in
area 1 and area 2. The sequences of send and receive words are the
same in area 1 and area 2.
• Not all nodes must participate in the data links.
Manually Setting Data Links
Manually set data links are used to create flexible data links that meet the
needs of the individual system.
• Data links are set in the Controller Link Unit or Board of each node using
the Controller Link Support Software.
• Area 1 and area 2 can be selected from PC memory areas, including the
DM Area and EM Area.
• A send area and its size can be allocated freely for each node.
• The sequence of receive nodes can be changed.
• Nodes can be set that only send or only receive data.
# 1
# 1
# 1
# 2
# 2
# 2
# 2
# 1
# 2
# 2
# 1
# 1
# 1
# 1
# 2
# 2
# 1
# 2
# 1 # 2
# 1 # 1
Area 1
Area 2
Area 1
Area 2
Send only
Example 1: The order of send and receive
nodes is free. Example 2: Some nodes can send data
without receiving data.
# 1
# 2
# 2
# 1
# 1
# 2
# 1 # 2
# 1 # 1
# 1 # 2
# 2 # 2
# 2 # 2
# 1 # 2
Area 1
Area 2
Area 1
Area 2
Receive only
Receive only
Several
words from
the begin-
ning of
area
Example 3: Some nodes can receive
data without sending data. Example 4: A node can receive only a
specified number of words from
the beginning of an area.