Destination Device Command - Omron CJ Series Connection Manual

9.2. Destination Device Command

The functions to read or write coils or registers are defined as ''Modbus functions'' in the
Modbus-RTU communication. The Destination Device can be operated (command execution)
by using the Modbus functions to read or write coils or registers defined by Destination
Device.
9.2.1. Function Code List
In the Modbus functions, a function code is allocated for each function. The following function
codes are available for Destination Device in this document.
This program performs Total Power ON Time Monitor by using the function ''Read from
Holding Register (function code: #03)''.
Code Function
(hex)
#01 Read Coil Status
#03 Read from Holding
Register
#05 Write to Coil
#06 Write to Holding
Register
#08 Loop-back Test
#0F Write to Multiple Coils
#10 Write to Multiple
Holding Registers
#17 Read/Write from/to
Multiple Holding
Registers
Additional Information
For details on function codes, refer to 8-5 Explanation of Each Function Code of the
Multi-function Compact Inverter MX2 Series Type V1 User's Manual (Cat. No. I585).
Description
Reads the coil status (ON/OFF).
Reads the contents of consecutive holding registers.
From the specified holding register, the specified number
of holding registers can be read.
Writes the ON/OFF status to a single coil.
Writes data to the specified holding register.
Checks the communications between the master and the
slave. Any value can be used for test data.
Rewrites the ON/OFF status to consecutive multiple
coils.
Writes data to consecutive multiple holding registers.
Reads data from and writes data to consecutive multiple
holding registers in a continuous manner.
9．Program
42