Android System Architecture

Android System Architecture:

1. Linux kernel

including Linux drivers and memory management, process management, power management and other programs, different Android version of the driver may not be universal.

2. C + + code library

This layer mainly includes code libraries written in C + + (Linux). So file), also includes the DALIVK virtual machine run is (runtime).

3. Android SDK API

This layer is a variety of libraries written in Java, except that these libraries are based on the Dalvik virtual machine format.

4. This layer relies primarily on the Android SDK API in the 3rd tier to accomplish a variety of functions.

The main work of Android system porting:

Android system porting can be divided into two parts: application porting and system porting

Android system porting refers to having the Android operating system run on a particular hardware platform. Android must be able to recognize the various hardware on the platform.

Android porting mainly works with porting the Linux driver, porting the HAL.

Linux kernel version

linux2.4,linux2.6 and linux3.x,

There are two ways to view the kernel version of a Linux system

1 performing uname–a on Linux endpoints

2 performing cat/proc/version on Linux endpoints

Definition rules for Linux kernel version numbers

The Linux version number consists of the main version number, the minor version number, the revision number, the fine-tuning version number, and the special tuning description for the specific Linux system.

Linux divides memory and peripheral devices into 3 categories: Character devices, block devices, and network devices.

Android System Architecture