Modbus/Tcp & Modbus Rtu Function Codes; Function Code Definitions; Table 8-1 Modbus/Tcp And Modbus Rtu Function Codes Definitions - Honeywell UDA2182 User Manual

8. Modbus/TCP & Modbus RTU Function Codes

8.1 Function code definitions

The UDA Modbus protocol uses a subset of the standard Modbus function codes to provide access to
process-related information. These standard function codes provide basic support for IEEE 32-bit floating
point numbers, 32-bit unsigned/signed integer and 16-bit integer register representation of instrument's
process data.
Repolling of data is not supported by this instrument.

Table 8-1 Modbus/TCP and Modbus RTU Function Codes Definitions

Function Name
Code
03 Read Holding
Registers
04 Read Input
Registers
16 (10h) Preset
Multiple
Registers
17 (11h) Report Device
ID
January 09
Read data in 16-bit Register Format (high/low). Used to read
integer or floating point process data. Registers are
consecutive and are imaged from the instrument to the host.
Provides Read access to any Analog Input Channel
positioned in any Rack or Slot.
Write Data in 16-bit Format (high/low). Used to write integer
and floating point data. Registers are consecutive and are
imaged from the host to the instrument.
Read instrument ID and connection information, ROM
version, etc.
UDA2182 Communications User Guide
Modbus/TCP & Modbus RTU Function Codes
Usage Max. Number of
registers per transaction
120
120
120
n/a
21