The Pico Cray is a cluster of 8 Picos and a controller Pico. All Picos are connected in parallel by an I2C bus. The controller is designated by one GPIO being held low, the processor Pico’s addresses are allocated automatically. The Controller Pico has a 320x240px display connected by SPI and a couple of buttons. As all of the Picos run the same software updating the cluster is easy.
Currently the cluster is programmed to run a Mandelbrot program. With each processor Pico calculating 120 points before returning them to the Controller.