UART hardware flow control

[andrew_aus]

Hi,

I plan on using the AT command firmware in an ESP32-WROOM-32D.

It appears to have hardware flow control (RTS/CTS) enabled by default.

I'm not using flow control and have left pins GPIO14 & 15 unconnected.

My question is what is the default state of the CTS pin (GPIO15) and what is the sense of CTS?

In other words I want to make sure that transmission out of the esp32 won't be blocked by default.

[Helen L]

RTS CTS seems to be optional. Mine only connects TX, RX, GND and it works fine. No need to connect CTS and RTS. Maybe you can have a try.

[andrew_aus]

Thanks Helen, that's all I needed to know.
I couldn't try it because our custom board is yet to be manufactured and was checking if we should add any pull resistors on cts, but obviously not required.
Cheers.