Manual

122 Publication 1757-UM007D-EN-P - December 2008
Chapter 9 Accessing HART Data
Example: HART Command 36
In this example, we are sending command 36, Set primary variable
upper range value, to a Rosemount 3044C module. The manufacturer
ID is 26 hex, the device type is 0d hex, and the device ID is 1b1ae
hex. The device is attached to channel 1 of a 1770-HT8 module.
The command file for command 36 contains:
Cmd 36 Set Upper Range Value
Rsp
There are no command parameters or response data, so the length to
send and expected reply length are both 7. The source file therefore
contains:
The reply contains:
There are 7 words of data, including 2 bytes of response data (the
HART response codes). The first response byte is 0, indicating the
command executed without error. The second response byte is 40
hex, indicating that the configuration changed.
Example Source File Contains
Word High byte, hex Low byte, hex Word data, hex
0 07 07 0707
1 00 10 0010
2 00 00 0000
3 26 82 2682
4 01 0D 010D
5AE B1 AEB1
6 00 24 0024
7 00 00 0000
Example Source File Reply
Word High byte, hex Low byte, hex Word data, hex
0 00 10 0010
1 80 00 8000
2 26 86 2686
3 01 0D 010D
4AE B1 AEB1
5 02 24 0224
6 40 00 4000