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Serial Port Operating Modes

To configure the serial port operating modes of the device:

  • DTU
  • General Settings

Navigate to the Protocol Format Select section and choose the operating mode under Type. The device supports three operating modes:

  • NET (Transparent data transmission)
  • MODBUS (MODBUS RTU → MODBUS TCP protocol conversion)
  • HTTPD (HTTP client mode)

The device supports four independent socket connections, labeled from Socket A to Socket D.

Socket A supports the following configurations:

  • TCP Client: The device acts as a client and connects to a TCP server.
  • TCP Server: The device acts as a server and listens for incoming TCP client connections.
  • UDP Client: The device acts as a client and sends UDP packets to a remote UDP server.
  • UDP Server: The device acts as a server and receives UDP packets from remote UDP clients.

Sockets B, C, and D support the following configurations:

  • TCP Client: The device acts as a client and connects to a TCP server.
  • UDP Client: The device acts as a client and sends UDP packets to a remote UDP server.

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NET Mode​

In this mode, users can enable transparent data transmission between the serial device and the network server using simple parameter configurations.

Set the operating mode to NET and click Save & Apply.

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Configure the serial port parameters and click Save & Apply.

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Set the device to TCP Client (TCPC) mode and enter the server address and port number. Click Save & Apply.

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After configuring all parameters, reboot the device for the settings to take effect.

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After rebooting, data transmitted from the serial port will be readable by the server.

Modbus Mode​

In this mode, the device can perform bidirectional protocol conversion between serial MODBUS RTU data and network MODBUS TCP data.

MODBUS mode supports four socket connections, and these connections operate independently.

Socket A supports both TCP client and server modes, while sockets B, C, and D support TCP client mode only.

Set the operating mode to Modbus and click Save & Apply.

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Set the device to TCP Server (TCPS) mode and enter the server port number. Click Save & Apply.

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HTTPD Mode​

In this mode, the serial device can send request data to an HTTP server. The device processes the data received from the server and forwards it to the serial device. By default, HTTP headers from server responses are removed. Users can enable or disable this feature using AT commands.

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