While the Raspberry Pi has very good support for an I2C bus, a lot of very cool chips – including the in system programmer for just about every ATtiny and ATmega microcontroller – use an SPI bus.

Of course, I went straight to the good folks at the Swiss Pi-Shop.ch and ordered one, which I received the next day. So, the first thing on my to-do list is to congratulate and thank both the Pi ...