Chapter 10 Data Links; What Are Data Links; Overview - Omron CX-PROGRAMMER V9 - REV 12-2009 Operation Manual

OMRON
CHAPTER 10
Data Links

What Are Data Links?

Overview

Data links automatically exchange data in preset areas between nodes (PLCs and/or computers) on a network.
Settings can be made either manually or automatically.
CX-Net operations can be used for all operations from setting up the PLC network to controlling data exchange.
Manual Settings
Manual settings enable more flexible allocations, including the send size for each node, the sequence of nodes for
sending and receiving, and the setting of nodes for sending only or receiving only. Use manual settings to create
flexible data links to meet the requirements of the individual system (e.g., efficient utilization of memory,
restrictions on allocated addresses, etc.).
Data link tables (i.e., tables that define data link area allocations) are generated by CX-Net or network support
software (such as Controller Link Support Software), and sent to all nodes for use.
Reception offset (reception
from start address + specified
Communications cycle time
Controller Link
Controller Link
Unit
PLC
PC
Note: The following table provides a general comparison of manual setup between Controller
Link and SYSMAC LINK.
Item
Node sequence
Send size
Receive-only nodes
Send-only nodes
Memory area
Receive size
number of words)
PLC
PC PC
Only part of area
Only part of area
Controller Link
Can be specified.
Supported
Supported
Can be specified.
Can be specified.
Can be specified.
Cannot be set.
PART 2: CX-Server PLC Tools
CHAPTER 10 – Data Links
PLC
SYSMAC LINK
Free
Supported
(Reception only is enabled by
setting the send area size at the
local node to 0.)
Cannot be specified. Fixed as
follows:
CS/CJ/CV Series: Area 1: CIO;
Area 2: DM
C Series: Area 1: LR; Area 2: DM
All or none
No (From start address only)
Can be set.
CX-Server PLC Tools_Page 89