Rockwell Automation 1770-KF2 Data Highway or Highway Plus Interface Module User Manual - Manual (Page 17)

Communication Concepts
Chapter 2
2-5
Stations
A station consists of a computer, or PC processor, and the module or
modules that interface it with the PCL. Within a station that contains a
KF2 module, an asynchronous link is required as an auxiliary link to the
network. PCL networks currently use PLC-5 processors, which interface
directly to the PCL; and no station interface module is required. You can,
however, connect other PCs, as shown in Figure 2.2.
Figure 2.2
PCL Network Connected to Various PC Processors
PLC-4
Loop
PLC-3
Processor
PLC-2/30
Processor
1773-KA
Module
1775-KA
Module
1771-KG
Module
KF2
Module
KF2
Module
KF2
Module
11300A
PCL
Other PCL stations can be computers that interface with the KF2 module
either directly or through a modem link, or a PCL-to-Data Highway
communication adapter (1785-KA), which you can use to connect a PCL
to the Data Highway.
PC Programming
All Allen-Bradley PC processors can receive command messages and
reply to them, and some can transmit commands. For an explanation of
how to program PCs to send and receive messages, refer to the user’s
manual for that particular station interface module or, in the case of a
PLC-5, the processor itself.