1. What computer system?
We can see the intuitive computer system is a computer. Includes a host, a display, keyboard, mouse, and then displayed on a display screen different, with a mouse click, keyboard input will be a corresponding operation interface.
2, a little deeper, how they work?
The computer system is composed of hardware and system software components that work together to execute the application.
3, a little deeper, what hardware is the? System software is what? What applications are?
Hardware is a fundamental component of a computer system, is familiar to everyone, CPU, memory, hard drives, motherboards and other.
System software is executed on the hardware layer of the control software. That is, we often hear of Windows XP, WIN7, Linux, platform, their purpose is to manage the various hardware, shielding the differences in hardware, application software provides a unified work.
Applications are executed on the system software layer software. They were management system software, the same time also enjoy a variety of resources and functions provided by the software interface system is often QQ we often use Thunder and so on.
4, entered, when the principles of computer work, doing what it has been in the process work?
When the computer work has been dealing with data, the data inside the computer can handle only two forms. 0 and 1, which is composed of the electrical characteristics of a semiconductor computer hardware. How to make 0 and 1 can represent a variety of information over the real world? Then they need to be combined and encoded.
CPU instruction set of components is made 0 and encoded.
Various characters and character we see on the display is encoded by a combination of 1 and 0 is made, and finally through a certain way and the simulated shape of the character is displayed on the text display.
Different meanings of the same 0 and 1 data composed in different places represented, how different this data?
The computer system of all information, data - contains the disk file, the program memory, the user data and a data transmission on the network, it is represented by a series of bits, i.e. bits 0 and 1. The only way to distinguish between different data objects is the context in which we read these data objects. For example, in a different context, the same byte sequence might represent an integer, string or machine instructions.
5, the program at different stages of representation - low-level instructions by a high-level language understandable to the human machine understandable
High-level language ( for example C language written) source code can be read person. But the computer did not understand, in order to allow the computer to know how to perform the procedure, you need to program each C language statements into a series of low-level machine language instructions, then these instructions, according to one executable object program and packaging format in the form of files stored on the hard disk.
6, execution of the program - is stored in the memory of the machine can understand low-level instructions being read, interpreted, executed
Will be the first program on the hard disk when executed by the operating system in accordance with certain rules and formats read and loaded into memory, and then performs the scheduling and handled by the CPU, a program execution process is complicated, it needs hardware systems different functions , coordination with the software.Anyway data stream input follows the whole process - "input-out principle, the processing of each device and then transfer.
7, roaming end
The computer system is composed of hardware and system software components that work together to execute the application.Information within the computer is represented as a set of components 0 and 1 bits. They interpreted differently depending on the context.
Other programs are compiled into various forms, at the beginning of the source code text, then the compiler and linker translated into binary executable.
The processor reads and interprets stored in main memory where the binary instructions. Since the computer takes a lot of time to copy data between the memory, I / O device and the CPU register, a storage device system was hierarchically arranged, at the top of the CPU registers. Followed by flash multilayer hardware cache memory, DRAM main memory, DRAM main memory and disk storage. Located at a higher level in the hierarchy of storage devices models faster than low-level storage devices, storage units but the price is higher.
The operating system kernel is the intermediary between the application and the hardware. It provides three main abstraction, an abstraction of file I / O devices. Virtual memory is a hard disk and main memory abstraction of the process is a processor abstraction main memory and I / O devices.
Finally, the network provides a means of communication between the computer system, a system from the point of view. It is a kind of network I / O device.