ESP8266 Community Forum

- Thu Feb 18, 2016 10:28 pm #41412 Hi,

I have a NodeMCU v1 board with a built in USB to UART and a USB port. I'd like to hook up a second USB to UART on the UART1 (GPIO2/D4?) pin of the ESP so I can have a tty constantly running without having to close the tty, flash the firmware and reopen it.

I have tried to connect the RX pin of my USB to UART thingy to the D4 pin of the ESP but I'm not seeing anything on the tty. If I use the tty with the built-in USB to UART, I'm getting the console output.

What am I missing? Do I have the correct pin?

- Fri Feb 19, 2016 4:11 am #41429 Did you also connect the ground of the second USB Uart?

- Fri Feb 19, 2016 5:52 pm #41484 I didn't, just the Rx pin to the Tx pin. Any GND pin on the ESP will do?

- Fri Feb 19, 2016 9:34 pm #41490 I cant get it to work. I have my second USB to UART's Rx pin connected to the ESP's Rx pin on D4 (which is GPIO2 on a NodeMCU from what I found) and the USB to UART's GND connected to one of the GND pins on the NodeMCU.

And yet when I connect to the second tty, I'm getting no output but if I use the built-in tty (the one used to flash the chip), I am getting the debug output I programmed.

I'm stumped.