B&B Electronics ADAM-6066 - Manual - Manual (Page 128)

ADAM-6000 Series User Manual 118
6.3.2 Modbus Function Code Introductions
To fullfill the programming requirement, there is a series of function code
standard for users reference¦
Code (Hex) Name Usage
01 Read Coil Status Read Discrete Output Bit
02 Read Input Status Read Discrete Input Bit
03 Read Holding Registers
04 Read Input Registers Read 16-bit register.
Used to read integer or floating
point process data.
05 Force Single Coil Write data to force coil On/Off
06 Preset Single Register Write data in 16-bit format
08 Loopback Diagnosis Diagnostic testing of the
communication port
15 Force Multiple Coils Write multiple data to force coil
On/Off
16 Preset Multiple Registers Write data in 16-bit format
Function Code 01
The function code 01 is used to read the discrete outputs ON/OFF status
of ADAM-6000 modules in a binary data format.
Request message format for function code 01:
Example: Read coil number 1 to 8 (address number 00017 to 00024) from
ADAM-6000 Modules
01 01 00 17 00 08
Command Body
Station
Address
Function
Code
Start
Address
High Byte
Start
Address
Low Byte
Requested
Number of Coil
High Byte
Requested
Number of
Coil Low Byte