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.

A Raspberry Pi Zero Shield that will connect a Zero or Zero W module to a 3.3V or 5V compatible Arduino board, is available from US-based Burgessworld Custom Electronics. The two boards are connected ...

The Rapid Radio is a 2.4GHz ISM band devices and is both Raspberry Pi And Arduino compatible and is supplied with full rapidradio source code is available at GitHub, that is free to use and modify ...

The Raspberry Pi itself is not open source hardware, because it relies on a Broadcom ARM processor (the BCM2835) for its computing, graphics processing, and memory. But Broadcom did recently ...