What Are Data Links?

Section 5-1

5-1 What Are Data Links?

Data links automatically exchange data in the preset areas between nodes (PLCs and/or computers) on one network. Data links can be freely created for CS/CJ-series PLCs, C200HX/HG/HE PLCs, CVM1, CV-series PLCs, CQM1H-series PLCs, 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.

CS/CJ-series Controller Link Unit Functions by Unit Version

Functions

Earlier version

Unit version 1.2

 

(Pre-Ver. 1.2)

 

 

 

 

 

CS1W-CLK21-V1

CS1W-CLK21-V1

 

CJ1W-CLK21-V1

CJ1W-CLK21-V1

 

 

 

Maximum number of data link

12,000 max.

20,000 max.

words (data link area for send-

 

 

ing/receiving that is created

 

 

for a single node in a single

 

 

CPU Unit)

 

 

 

 

 

Data Link Area

The same area cannot be

The same area can be

 

allocated for both Area 1

allocated for both Area 1

 

and Area 2.

and Area 2.

 

 

 

Note Use the CX-Net in CX-Programmer version 5.0 or higher to set a data link area in which the number of send and receive words exceeds 12,000 words, or to set data link tables that allocate the same area for Area 1 and Area 2.

Data link areas can be manually set by inputting data link tables using 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

Example 1: The order of send and receive

Example 2: Some nodes can send data

nodes is free.

 

 

without receiving data.

 

# 1

 

 

 

# 2

 

# 1

 

 

 

 

# 2

Area 1

 

 

 

 

 

 

 

Area 1

 

 

 

 

 

 

 

 

# 1

 

 

 

# 2

 

 

# 1

 

# 1

 

 

# 2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

# 1

 

 

 

Send only

 

# 2

 

 

 

 

 

 

# 1

 

 

 

# 2

 

# 1

 

 

 

 

# 2

Area 2

 

 

 

 

 

 

Area 2

 

 

 

 

 

 

# 2

 

 

 

 

 

# 1

 

 

 

 

 

 

# 1

 

 

 

 

# 1

 

 

 

 

 

# 1

 

 

# 2

 

 

 

 

 

 

 

 

 

 

 

# 2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

106

Page 129
Image 129
Omron C200HW-CLK21, CVM1-CLK21 What Are Data Links?, CS/CJ-series Controller Link Unit Functions by Unit Version