5-1
Section
What Are Data Links?
64
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 created for C200HX/HG/
HE PCs, CV-series PCs, CS1-series PCs, and IBM PC/AT or compatible com-
puters.
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 the
CLK Data Link Setting Utility in the FinsGateway or the Controller Link Support
Software. Data link tables are created to define the data links. These tables
enable user-specified allocation of data link areas.
•
Data links can be set automatically from a Programming Device. With auto-
matically 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 (first link 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
# 1
# 1
# 1
# 2
Area 1
# 2
# 2
# 2
# 1
# 2
# 2
Area 2
# 1
# 1
# 1
# 1
# 2
# 2
Area 1
# 1
# 2
# 1
# 2
Area 2
# 1
# 1
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
Area 1
# 2
# 2
# 2
# 2
# 1
# 2
Area 2
# 1
# 2
# 2
Area 1
# 1
# 1
# 2
# 1
# 2
Area 2
# 1
# 1
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.
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
CLK Data Link Setting Utility in the FinsGateway or Controller Link Support
Software or CX-Programmer.
•
At PCs, area 1 and area 2 can be selected from 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.
•
Only part of send data can be received and an offset can be used to specify the
beginning of the desired part.
