ESP32 Forum

Hi,

Is anybody here to tell me how to use the UART1 (GPIO9 & GPIO10)?
By default, only UART0 and UART2 can be used. To use UART1, we have
to redefine the pins because default pins of UART1 such as GPIO9 and GPIO10
are internally connected to the SPI flash memory.

What is the meaning of "redefine"?

Thanks,
Bernd

Depending on what SDK you use, there should be a way (usually when you initialize the UART) to indicate what GPIOs you want RxD, TxD etc routed to. You can use mostly any (not otherwise occupied, and keeping in mind that some GPIOs are input-only) GPIO there.