Vaisala HMP110REF

Appendix A _________________________________________________________ Modbus Reference
VAISALA ________________________________________________________________________ 75
APPENDIX A
MODBUS REFERENCE
This appendix describes the Modbus protocol implementation of the
HMP60/HMP110 series probes. For information on Modbus
communication and instructions on accessing Modbus mode and
configuring the communication settings, see Modbus Communication on
page 37.
- Supported Modbus functions are described in Table 17 below.
- Supported measurement and configuration registers are described in
Table 18 on page 76.
- Device identification objects are described in Table 19 on page 78.
- Communication test registers are described in Table 20 on page 78.
Supported Modbus Functions
Table 17 below lists the function codes supported in the
HMP60/HMP110 series Modbus RTU implementation.
Table 17 Supported Function Codes
Function
Code
(decimal)
Function Code
(hexadecimal)
Function Name
(as defined by the specification)
Notes
3
03
Read Holding Registers
See Table 18 on page 76
for available registers.
16
10
Write Multiple Registers
See Table 18 on page 76
for available registers.
43 14
2B 0E
Read Device Identification
See Table 19 on page 78
for available device
identification objects.
NOTE
After power
-up, wait for two seconds before sending Modbus requests.