How much volt is TXD RXD GND ?Yes Baud Rate is a speed. If your USB to UART cable doesn’t work after the first connection, it did not mean that UART is locked. It actually meant that you did not connect UART pinout correctly, and that incorrect connection broke your USB to UART cable, for example, you might connect 3.3V pin to GND pin. The only solution now is to get a new USB to UART cable and double check RX TX and GND pin.
Do you know the command to get k1_unique after successfully connected the set-top-box to the computer? What software do you use to communicate with the set-top-box?possibly that is BBS port the conector
TX is 115200.
first find TX in board (may be in a resistance)
use the RX from you computer
Nope because I don’t know which software to use.