CHAPTER 5Accessing Hardware
To be truly useful, an embedded device must be able to interface with hardware components. This chapter describes how you can access general purpose input/output (GPIO) ports, transfer data with the RS232 serial port, and interface with devices on the inter-integrated circuit (I2C) and serial peripheral interface (SPI) busses. Further, you will learn how to obtain information about the charging state, processor speed, and system identification.
What Are GPIO Ports?
General purpose input/output (GPIO) ports are probably the most frequently used way for a microcontroller to contact its environment. A GPIO port can be initialized and used either as an input or output line. A typical example of an output line is one to ...