Rockwell Automation 1770-HT8 SMART TRANSMITTER - Manual (Page 81)

Communicating with the Smart
Transmitter Interface
Chapter 4
Communicating with the Smart Transmitter
Interface
4-16
The other bits in this byte are used for communication between host
computers residing on the Data Highway Plus and the Smart Transmitter
Interface. This communication requires special software on the host
computer and can only occur with programmable controllers which support
“pass through” functionality.
ATTENTION: You must program the host processor to clear
all bits except for bit six in this byte. Your application may
operate in an unpredictable and unreliable manner if this is not
done.
Smart Transmitter Interface Parameter
The last byte of the header provides an additional parameter required by
the Smart Transmitter Interface commands hexadecimal 10, 20 and 21. If
you are not using any of these commands set this field to 0 as indicated in
Table 4.G.
Smart Transmitter Interface Data
Smart Transmitter Interface commands hexadecimal 2 and 10, require this
extended data field to provide additional information to the Smart
Transmitter Interface. When not required, the Smart Transmitter Interface
ignores any data received in this field.
Figure 4.9 illustrates the format of Smart Transmitter Interface packets
transmitted by the Smart Transmitter Interface to the host processor. These
packets are similar those sent by the host processor.
Smart Transmitter Interface Command
This byte contains the number for the Smart Transmitter Interface
command which the Smart Transmitter Interface is sending to the host
processor.
Smart Transmitter Interface
Packets Sent by the Smart
Transmitter Interface