ESP8266 Community Forum

- Mon Apr 16, 2018 12:06 pm #75416

You can wire it that way, but I only use rx,tx, and ground on my setup.

I do the same. RX, TX, and Ground. I have about ten development setups wired like this. GPIO0 and reset are handled manually on the boards.

- Mon Apr 16, 2018 3:08 pm #75420 One more doubt. To boot into UART mode, pin config of esp, i.e 15-0-2 should be 0-0-1. While pin15 is connected to ground with pulldown resistor in between, and pin0 either connected to a manual switch or serial DTR with pullup resistor to 3.3 V source, why pin2 is left floating? How it will be high when esp is reset??

- Mon Apr 16, 2018 5:58 pm #75427 Modules normally have a blue led and series resistor connected to GPIO2 and to VCC. That produces the required high.

On my own PCB designs I always include a pull up resistor on GPIO2.

- Tue Apr 17, 2018 6:52 am #75432 Thanks. Now its clear