You only really need two data wires to transfer a ton of data. Standards like UART, USB2, I2C, SPI, PS/2, CAN, RS232, SWD (an interface to program MCUs), RS485, DMX, and many others, all are a ...
I2C is a two wire, clock synchronized protocol with a bi directional data line and a uni directional clock line. Its simplicity lies in its use of only two lines for communication and its complexity ...
Several of the Mid-Range Enhanced Core PIC16 microcontroller devices have a Master Synchronous Serial Port (MSSP). The MSSP module can be used to implement either I2CTM or SPI communications protocol.