ESP8266 Community Forum

- Mon Nov 03, 2014 3:41 am #2173 I couldn't seem to find this info elsewhere but from what I have been reading it sounds like there is a second UART. I found a reference to GPIO2 being able to be used as U1TXD but does anyone know if there's a corresponding U1RXD and how I would configure this for use?
Cheers,
Ben

- Mon Nov 03, 2014 3:57 pm #2207 In example 2nd uart use only for tx(for debug)

- Wed Nov 05, 2014 9:48 am #2265 I got a response from Espressif about this and I quote:

uart1 RX is multi-used for spi-flash , so there is only TX for uart1. uart0 TX RX are both available.

So, unfortunately only one full UART available if you're using the SPI Flash.

- Sat Dec 19, 2015 2:42 pm #36799 The problem with UART0 is that RX0 is unavailable if you're using I2S, b/c its the Data pin.

Finding out that UART1 is TX only, I'm going to have to use I2C to communicate with my Diag board.

That's so silly. But thanks for the info guys.