Manual

120 Publication 1757-UM007D-EN-P - December 2008
Chapter 9 Accessing HART Data
Word 6
The low byte contains the HART command. For example, to
send Read Primary Variable, enter 01 hex.
The high byte contains the number of bytes of parameters from
the command file.
Words 7…
If there are any parameters to the HART command, the following
words contain those parameters.
Word N
The last word contains 0. Both the upper and lower byte (check byte)
should be 0.
Reply Data
When the MSG command executes, the reply to the command will be
stored in the Destination tag.
The following table shows the contents of the reply.
Reply Contents
Word High Byte Low Byte
0 Channel - 1 Interface command, usually 10
hex
1 Interface status Interface error
2 HART address Manufacturer ID HART delimiter = 86 hex for ACK
with long frame address
3 Device ID, most significant byte Manufacturer device type, from
HartCfg.exe
4 Device ID, least significant byte Device ID, middle byte
5 Byte count, number of following bytes
of response data until the check byte
HART command
6 HART response code, second byte, 0
for no error
HART response code, first byte,
0 for no error
… data data
data