Thinking about the SPI library ...?

[awneil]

Late update:

@awneil

After all, it's just another microcontroller - it could be programmed to do anything one wishes ...

For example, people have done this to give USB HID on a UNO R3:

Arduino UNO as HID

I am trying to build a keyboard and a mouse which is connected to PC by USB and with a few buttons/Joystick as inputs the Arduino UNO reads those inputs and presses the specified keys. Basically Arduino UNO used as a HID. If anyone has a tutorial related to my topic, it would be I thankful of you.