Rockwell Automation 1779-KP5_KP5R ORD.1779-5.3 - Manual (Page 34)

Addressing from Data Highway II
Chapter 4
4Ć4
Addressing Data Highway Plus from a PLCĆ2
To send a message from a PLC-2 (1779-KP2) on Data Highway II to a
Data Highway Plus node, you use the following address format in the
communication zone of your ladder-logic program (NNN = Node,
UUU = User):
NNN UUU
=
The 1779-KP2 does not support the network layer. The LINK value is
automatically 00 (local link).
The NODE value is the node address of the 1779-KP5 that connects you
to the destination Data Highway Plus link (the link that contains the node
you want to communicate with).
The PLC-2 USER value is determined differently than for other nodes on
Data Highway II. Since a PLC-2 cannot send to Addresses 00 to 07 octal
(these addresses are defined by the PLC-2 for processor work area), a
PLC-2’s access to other node addresses would be extremely limited (only
Stations 10 through 20 octal). To solve this problem, the PLC-2 uses a
formula to convert the node addresses. This allows the PLC-2 to access
all allowable addresses (02 through 20 octal) on Data Highway Plus.
To determine the PLC-2 USER value of a Data Highway Plus node, add
10 (octal) to the Data Highway Plus address. For example, Data Highway
Plus Node 12 (octal) has a PLC-2 USER value of 22:
12 + 10 = 22 (octal)
For more information on addressing a PLC-2 on Data Highway II, refer to
the PLC-2 Family Interface (1779-KP2, -KP2R) User’s Manual
(Publication 1779-6.5.3).