Rockwell Automation 1779-KP3R DATA HIGHWAY II - Manual (Page 36)

Chapter
3
3Ć1
Programming
This chapter contains information on programming your PLC–3 to
communicate on the Data Highway II network. We will discuss the
information you place in a PLC–3 message send instruction. The PLC–3
Message Send instruction itself is covered in greater detail in the PLC–3
Programmable Controller Programming Manual (publication 1775–6.4.1).
This chapter covers the following topics:
transferring data
the TO and FROM qualifiers
the format for addressing Data Highway II nodes
the format for addressing the memory in Allen–Bradley PLC
Programmable Controllers
The terms onlink and offlink are used extensively throughout this chapter
and we assume that you are familiar with them. For an overview of these
concepts, refer to Chapter 1.
This section covers the commands and qualifiers you can use to transfer
data using the KP3 module.
The commands you can use are listed in the table below:
Command
:
Use to:
MOVE tell the KP3 to move a bit, a word, or a contiguous block of words. This is usually
used to move data to or from a remote node on Data Highway II, but you can
also use it to move data to and from a node on Data Highway Plus or within the
PLC-3.
TMOVE tell the KP3 to move a bit, a word, or a contiguous block of words. This can be
used to transfer data to and from an onlink Data Highway II node. It is usually
used to transfer small amounts of time-critical data in a small amount of time.
A qualifier is a word used to specify the details of the data transfer. The
qualifiers you can use with the commands above are listed in the
following table.
Chapter Objectives
Transferring Data