RTS & CTS support for ATSAMD based boards (Arduino zero)

[vss]

Hi,

1. Does ATSAMD21G support RTS and CTS (Full UART ) ?

2. If yes, how do I add/enable these pins in a SERCOM of the microcontroller core files (probably variant.cpp)?
   Any pointers with reference to Arduino Zero core would be very helpful.

[ron_sutherland]

1. Yes

2. I am somewhat lost in these ARM core files but they are at

GitHub - arduino/ArduinoCore-samd: Arduino Core for SAMD21 CPU

After looking a little I see "#define NO_RTS_PIN 255" and "#define NO_CTS_PIN 255". They seem to be used by the first object initializer, but the next initializer lets the user define the RTS and CTS pins.

arduino/ArduinoCore-samd/blob/a7c33fea4b06f4032272d18c12487d128b5e3eb8/cores/arduino/Uart.cpp#L32

Next problem is figuring out which pins can be used as RTS/CTS for the SERCOM you want to use.