Rockwell Automation 1756-DHRIO_DHRIOXT ControlLogix Data Highway Plus-Remote I/O Communication Interface Module - Manual (Page 46)

46 Rockwell Automation Publication 1756-UM514C-EN-P - June 2014
Chapter 4 Using Programming Software in DH+ Applications
Use RSLinx to Create a
Routing Table DH+ protocols do not use the Control and Information Protocol (CIP), the
communication protocol used in the ControlLogix architecture. The
1756-DHRIO and 1756-DHRIOXT modules are the transition point from the
DH+ network to ControlLogix. In this capacity, the 1756-DHRIO and
1756-DHRIOXT modules serve as the DH+ message source and require a full
message route, or path, to deliver the message. A routing table, using link IDs and
node addresses, provides the full path.
What Is a Routing Table?
Before you can create a routing table for your 1756-DHRIO and
1756-DHRIOXT modules, you must assign link IDs to all networks (including
ENET and CNET) that route information through the module. Link IDs are
numbers from 1…199.
DH+ module addressing provides the link IDs and node addresses. The routing
table translates link IDs and node address information into path, or routing,
information. Thus, the routing table specifies a 'map' to other links in the system.
Routing tables are configured at each node to build accurate connections.
ControlLogix supports Pyramid Integrator (PI) routing and is backward-
compatible with DH+ products. The architecture also provides newer routing
protocols that are designed to make it easier to maintain a system. The
1756-DHRIO and 1756-DHRIOXT modules, as the transition points between
the ControlLogix architecture and the DH+ network, enable ControlLogix to
use new protocols while maintaining the option of backward-compatibility with
DH+ products.
Pyramid Integrator Emulation
Each Pyramid Integrator chassis has a routing table in it that tells the chassis
where each DH+ link is in relation to that chassis. The routing table uses a
link
ID to identify each link. You must enter a port for each link that is local to that
chassis and a bridge address
for each link that is remote from that chassis.
Each bridge can have a list of link IDs that are accessible through that bridge. A
bridge can be any device that supports the Pyramid Integrator style of routing,
including the following:
• Pyramid Integrator
• ControlLogix chassis
• WinLinx Gateway
• RSLinx workstation hosting DDE topics or applications that accept
unsolicited messages