Rockwell Automation 1771-KA2 Communication Adapter Module - Manual (Page 37)

Chapter
4
4-1
Commands
The primary function of a KA2 module is to transfer data to and from its
station processor. The module is instructed to transfer specific units of
data by user-programmed commands. The communication adapter module
transmits and receives the following set of non-privileged commands:
Protected write
Protected bit write
Unprotected write
Unprotected bit write
Read
These commands are of three general types: write, bit write, and read.
(Refer to Figure 4.1). The write and read commands transfer word data
between the data table of the local station processor and the data table of a
remote station processor. The bit write command controls ON/OFF status
of one or more memory bits at a remote station processor.
Figure 4.1
Module Command Summary
16-Bit Words
16-Bit Words
Data Table at
Local Station Processor Data Table at
Remote Station Processor
Individual Bit
Write
Bit Write
Read
Communication
Adapter Module
General