Meadow has support for the following digital communication protocols:

Protocol Speed Multiple Peripheral Support # of Wires Common use cases  
I2C (Inter Integrated Circuit) Slow to Medium (100Khz up to 5MHz) Yes Two   Short distance. Sensors, LCD displays, low-speed peripherals.
SPI (Serial Peripheral Interface) Fast (1MHz+) Yes Minimum of 3, Typically 4. High-speed, data-heavy peripherals such as cameras and displays.  
UART (Serial) Slow No 2 Used for communication between boards or with computers.  
CAN (Controller Area Network)          
I2S (Integrated Inter-IC Sound Bus)          

These docs are open source. If you find an issue, please file a bug, or send us a pull request. And if you want to contribute, we'd love that too!