Allen-Bradley 1779-KFMR User Manual page 158

Chapter 10
command initiator of your host computer match each command with the
corresponding reply.
LINK — This one-byte field specifies the destination Data Highway II
link (000 — 377 octal) within the network for this RC control message
packet. With only one Data Highway II link in the network, enter the
LINK-field value 000 octal.
NODE — This one-byte field specifies the destination node
(001 — 376 octal) within the destination link for this RC control message
packet. The value of this field corresponds to the octal value you select
with the LINK-ADDRESS thumbwheel switches at each node interface.
When sending a message to initiate a remote command, you can send a
node field value of 377 as a special code to broadcast the initiate
command to all nodes of the link.
USER — This one-byte field specifies the destination channel within the
destination node for this RC control message packet. Since a destination
node for an RC control message packet has only one possible channel,
enter a USER-field value of 1.
In a command packet, these LINK, NODE and USER fields combine to
fully specify the network address of the remote station that is to receive
the packet and store its remote command. In a reply packet, these fields
specify the network address of the remote station sending the reply.
RC Control Message Fields (Application Layer)
Figure 10.1 shows the format of the RC control message packet including
the RC control message fields at the application layer. The RC control
message fields are the fields defined at the application layer that tell the
remote station what to do with the remote command. Here we describe
these RC control message fields:
CMD (Command) — This one-byte field specifies the type of action to
be performed by the command executor at the station which stores the
remote command. This field is only in each RC control command