I recently prototyped and programmed a system that used some SPI sensors on an Arduino Uno. I wanted to get the size down a bit, so I was thinking I might buy an Arduino Nano and re-wire my system around that. The problem is that I have seen mention of SPI not working on the Nano. From the Nano product page:
These pins support SPI communication, which, although provided by the underlying hardware, is not currently included in the Arduino language.
Yet I have also seen mention of SPI working on this board, or at least people saying that it should. Someone asked a similar question on Stack Overflow and was told that it should work with the same level of support as I2C, even if it isn't built in to the core framework. But that answer does not definitively answer the question of whether SPI does work, and it doesn't explain any caveats that one may come across. In this question, the OP's premise is that their SPI device works on the Nano but not on other boards; this seems to be a strong indication that SPI does work.
I figured it would be worth it to buy a Nano 3 and see if it worked. SPI devices did not work on that board, including the same radio module mentioned in the question linked to above. So, I am inclined to believe the Arduino product page when they say it isn't supported. But that still isn't satisfactory, and it is the opposite conclusion from that of the other questions: The hardware is all there and the software framework is in place, so what does one need to do to make SPI work on the Arduino Nano? Why is it that some sources say it works while others say it doesn't?