When this problem occurs, you can refer to the following solutions:
1. First make sure you have an RS232 to usb data cable, and then connect the data cable to the computer
2. Now connect the USB to the computer, and then double-click on the serial port software, you can test
3. After opening the serial port software, click to select your serial port and confirm that the serial port driver is installed
4. Now you can open the serial port, click \"Open serial port\"
5. Now send, enter the data you want to send in the send window, just enter it directly
6. Now click to select the timing send better viewing effect
7. Short connect the pin 2,3 of your serial port or use the circuit board of the serial port to connect the serial port line, and now you can receive data, indicating that the serial port conversion is successful
LED display rs232 interface is connected to the computer serial port communication, if you want to USB interface, only need to use a USB to 232 interface device to convert the USB signal into rs232 signal can be.