Android system porting and Driver development overview

Through this chapter of learning, I learned some basic knowledge, as well as the use of program control LED light process.

1,android System Architecture

The Android system is divided into 4 tiers, namely the Linux kernel, c/S code base, Android SDK API, application. The Linux kernel is responsible for the most basic functions, such as memory management, security, process management, network protocol stacks, and drive models. The code library for C + + is responsible for the encapsulation of some common functions in the Android system, such as decoding, and the Java Virtual machine is also in this layer. The Android SDK API provides third-party applications for third-party application developers with APIs that third-party application developers can use to facilitate the development of third-party applications, and this layer also provides a range of services and systems. The application layer is a layer of direct user contact, the top level, and most applications are implemented by invoking the Android SDK API.

2. Classification of equipment

Devices are divided into character devices, block devices, network devices.

A character device is a device that must be accessed sequentially in serial order, such as a touchscreen, mouse, or keyboard. Block devices are a class of I/O devices that store information in a fixed-size block, each with its own address, more efficient, more convenient, and more complex than a character device. Almost all of the devices belong to these three categories, but there are special architectures for special devices.

Android system porting and Driver development overview