Modbus Software Definition; Supported Modbus Rtu Functions - LMI Excel XR Series Manual

4.0 Modbus Software Definition

Start Hex Quantity
Address
0x0001 14
0x0001 76
0x0001 27
0x0065 11
0x0001 43

4.1 Supported Modbus RTU Functions

Code Hex Name
01 0x01 Read Coil Status
02 0x02 Read Discrete Inputs
03 0x03 Read Holding Registers
04 0x04 Read Input Register
05 0x05 Write Single Coil
06 0x06 Write Single Holding Register
07 0x07 Read Exception Status
15 0x0F Write Multiple Coils
16 0x10 Write Multiple Registers
17 0x11 Report Server ID
MODBUS SOFTWARE DEFINITION
Type Description
Coils Coils are used to execute basic commands such as
toggling on/off status, setting operating mode, or setting
units.
Holding Registers Holding Registers are 2 bytes each and used to
read/write data such as flow rate, time, and setting
values.
Discrete Inputs Discrete Inputs are read-only bits used to determine the
status of items such as on/off status, current operation
mode, digital I/O status, or homescreen display.
Discrete Inputs Discrete Inputs are read-only bits and this range is used
to determine the status of alarms. Each alarm has its
own discrete input bit that can be monitored.
Input Registers Input Registers are read-only and are used for general
information such as current flow rate, analog I/O values,
totalizer information, and firmware revisions.
Description
Read the status of contiguous coils.
Read the status of contiguous discrete inputs.
Read the contents from a contiguous block of
holding registers.
Read the contents from a contiguous block of input
registers.
Write the status of a single coil.
Write the contents a single holding register.
Read the exception status for the following
Exception Codes:
01: ILLEGAL FUNCTION
02: ILLEGAL DATA ADDRESS
03: ILLEGAL DATA VALUE
Write the status of contiguous coils.
Write the contents of contiguous holding registers.
Read the device slave ID.