nickgammon:
Near the bottom of this page is example code for the Arduino for using the USART in SPI master mode:Gammon Forum : Electronics : Microprocessors : SPI - Serial Peripheral Interface - for Arduino
I know this post is old but can you explain how/which serial port is selected to run in SPI master mode? For example I wish to make Serial1, not Serial0 SPI master mode on my 2650. That way I can continue to print out data/debugging on Serial0 while the sketch is running, and my SPI devices are running on the normal SPI port and the Serial1.