TU RS485/ETH serie
CD Automation srl
20
Read Holding Read the Holding Registers from a Modbus slave device
Reads the values of
N
holding
Register
s (Modbus function 0x03, Registers 4xxxx ) from a Modbus slave
device and writes the values in the selected Internal Registers. In case of missing response or wrong
response by the slave device, the Registers of destination are not updated and the value of the System
Register “COM Errors” is increased.
Variables:
Address
Modbus address of the slave device (1÷247)
Register
Address of the first Register to read (the mapping Registers starts from 0)
Num
Numbers of Registers to read (1÷16)
Dest
Address of the first Internal Register wherein the read values are written to.
Delay
Delay time between the reception of the response and the execution of the next instruction
Write
Write the Holding Registers of a Modbus slave device
Writes the values of
N
Internal
Register
s in
N
Holding
Register
s of a Modbus slave device (Modbus function
0x16, Registers 4xxxx ). In case of missing response or wrong response by the slave device, the Registers of
destination are not updated and the value of the System Register “COM Errors” is increased.
Variables:
Address
Modbus address of the slave device (1÷247)
Register
Address of the first Register to write (the mapping Registers starts from 0)
Num
Numbers of Registers to write (1÷16)
Source
Address of the first Internal Register from which the values to write are withdraw from.
Delay
Delay time between the reception of the response and the execution of the next instruction.
Read3000
Read the I/O Registers from a Modbus slave TU-E3000 series device
Reads the I/O values from a Modbus slave TU-E3000 series device and writes the values in the Internal
Registers. The function will generate the proper Modbus command and will process the response.
In case of missing response or wrong response by the slave device, the Registers of destination are not
updated and the value of the System Register “COM Errors” is increased.
Refer to the technical documentation of the TU-E3000 series device for the complete description of the I/O
Registers.
Variables:
Device
Selection of the TU-E3000 series slave device.
Address
Modbus address of the slave device (1÷247).
Resource
Type of data to read (analog inputs, digital inputs , etc...)
From
First Resource to read.
To
Last Resource to read.
Dest
Address of the first Internal Register wherein the read values are written to.
Delay
Delay time between the reception of the response and the execution of the next instruction.
Read Input
Read the Input Registers from a Modbus slave device
Reads the values of
N
input
Register
s (Modbus function 0x04, Registers 3xxxx ) from a Modbus slave device
and writes the values in the Internal Registers. In case of missing response or wrong response by the slave
device, the Registers of destination are not updated and the value of the System Register “COM Errors” is
increased.
Variables:
Address
Modbus address of the slave device (1÷247)
Register
Address of the first Register to read (the mapping Registers starts from 0)
Num
Numbers of Registers to read (1÷16)
Dest
Address of the first Internal Register wherein the read values are written to.
Delay
Delay time between the reception of the response and the execution of the next instruction.