Communication with other systems in the vicinity of the target is enabled by a few protocols. Most microcontrollers designed for embedded systems support the most common interfaces that control and discipline the access to serial lines. Some of these protocols are so popular that they have become the standard for wired inter-chip communication among microcontrollers, and for controlling electronic devices, such as sensors, actuators, displays, wireless transceivers, and many other peripherals. This chapter describes how these protocols work, specifically focusing on the implementation of the system software, through examples running on the reference platform. In particular, this chapter contains the following sections:
- Introducing serial communication
- UART-based asynchronous serial bus
- SPI bus
- I2C bus
