Modbus RTU Slave
To configure a serial port as a Modbus RTU slave, click Serial on the menu, and then select Modbus RTU Slave
from the Port Type drop-down list (see Figure 36). Configure the parameters described below.
Figure 36 Serial Configuration - Modbus RTU Slave
Port Type
Select Modbus RTU Slave from the drop down list.
Data Rate
Select the serial data rate to match that of the serial device that is connected and
communicating via the port. Baud rates available from 110 to 230400 baud.
Data Format
Defines the number of data bits, parity and start/stop bits used to communicate with
the serial device.
Flow Control
Flow control is used by some serial devices to regulate the flow of data by turning on/
off flags that are used to tell the connected serial devices to start or stop transmitting
data. The RS-232 supports CTC/RTS hardware flow control.
Modbus Slave
Device ID
Address of the onboard Modbus RTU slave/TCP server. This is the address that will
be polled by an external Modbus master/TCP client. Default address is 255 and can
be set here or on the Modbus TCP page.
Save Changes and
Activate
Save changes to non-volatile memory and activate the process.
Serial Gateway
To configure the port to allow point-to-point or point-to-multipoint transparent serial data transfers, click Serial
on the menu, and then select Serial Gateway from the Port Type drop-down list on the Serial Configuration page.
Configure the parameters described below. Note that different fields are presented depending on whether you
select the gateway mode as
“Server” (Figure 36), or “Client” (Figure 38).
