- baudrate 9600
First can you double check the output signal is RS232 or TTL? The correct input signal should be TTL, which differs from RS232.
You have to find a USB-TTL testing bridge cable or PCB Board to test, for example, CH340, FT232, CP210x.
The board rate looks correct 9600.
The wiring please try:
your device TXD -> “Serial to HID Keyboard Emulator” RXD your device RXD -> “Serial to HID Keyboard Emulator” TXD GND - GND
And last, you need to send by hexadecimal from your device, and receive a text string on the USB HID side. e.g.
0x48 0x65 0x6c 0x6c 0x6f -> Hello (open a text editor to see)
Best regards,