In Industrial Internet of Things (IIoT) applications, USR-TCP232-304, as a common serial server device, plays a crucial role in converting serial communication into TCP/IP network communication. Meanwhile, the Industrial 4G Router is a key device for network connection, responsible for forwarding data packets between different networks. Therefore, the communication between USR-TCP232-304 and Industrial 4G Router is a critical step in building a stable and reliable IIoT system.

I. Basic Working Principle of USR-TCP232-304

USR-TCP232-304 serial server primarily converts RS-232/422/485 serial signals into TCP/IP network signals, enabling remote access and control of serial devices. It integrates a network processor that can receive network data from the Industrial 4G Router, convert it into serial data, and output it to the connected device. Conversely, it can also convert data sent by the serial device into network data and send it to a remote client through the Industrial 4G Router.

II. Connection Method between USR-TCP232-304 and Industrial 4G Router

The connection between USR-TCP232-304 and Industrial 4G Router typically employs a direct Ethernet cable connection. First, the Ethernet Port of USR-TCP232-304 needs to be connected to the LAN port of the Industrial 4G Router using an Ethernet cable. This allows USR-TCP232-304 to access the local area network created by the Industrial 4G Router.

III. Network Configuration and Communication Settings

1. IP Address Configuration: To ensure normal communication between USR-TCP232-304 and the Industrial 4G Router, it is necessary to configure an IP address for USR-TCP232-304 that is within the same subnet as the Industrial 4G Router. This can usually be done through the Web configuration interface or serial configuration tool of USR-TCP232-304. Once configured, USR-TCP232-304 can act as a node within the local area network and communicate with other devices.

2. Port Mapping: If remote access to USR-TCP232-304 is required through the internet, port mapping settings need to be configured on the Industrial 4G Router. Port mapping allows external networks to access specific ports of devices within the Industrial 4G Router. When configuring port mapping on the Industrial 4G Router, the IP address of USR-TCP232-304 and the port number to be mapped (usually the TCP listening port of USR-TCP232-304) need to be specified. This allows external networks to indirectly access the USR-TCP232-304 device by accessing the public IP address and mapped port of the Industrial 4G Router.

3. Firewall Settings: In some cases, the firewall of the Industrial 4G Router may block communication with USR-TCP232-304. Therefore, it is necessary to ensure that the firewall rules of the Industrial 4G Router allow the necessary network communication for USR-TCP232-304. This typically includes allowing TCP/IP protocol packets and opening the ports used by USR-TCP232-304.

IV. Communication Testing and Troubleshooting

After completing the above configurations, network testing tools (such as ping commands, telnet tools, etc.) can be used to test the communication between USR-TCP232-304 and the Industrial 4G Router. If communication failures are detected, troubleshooting can be conducted from the following aspects:

1. Check Network Connection: Ensure that the Ethernet cable connection between USR-TCP232-304 and the Industrial 4G Router is secure and not loose or damaged.

2. Verify IP Address Configuration: Confirm that the IP address of USR-TCP232-304 is within the same subnet as the Industrial 4G Router and does not conflict with other devices.

3. Review Port Mapping: If remote access is required, ensure that the port mapping settings on the Industrial 4G Router are correct and not blocked by other rules.

4. Examine Log Information: Utilize the logging functionality of USR-TCP232-304 or the Industrial 4G Router to check for any relevant error messages