The core of the motherboard is the motherboard chipset , which determines the specifications, performance and general functions of the motherboard. We usually say "865PE motherboard, 865PE refers to the motherboard chipset. If the CPU is the heart of the entire computer system, then the chipset will be the trunk of the entire system. For the motherboard, the chipset almost determines the function of this motherboard. , Which in turn affects the performance of the entire computer system. The chipset is the soul of the motherboard. The performance of the chipset determines the performance and level of the motherboard. This is because the CPU has a wide range of models and types, and different functional characteristics. , If the chipset cannot work well with the CPU, it will seriously affect the overall performance of the computer, or even fail to work normally.
North Bridge and South Bridge
In the traditional chipset structure, the South Bridge chip and the North Bridge chip have been matched, and their specific positions can be found on the motherboard. Generally, we can find a heat sink near the CPU socket on the motherboard, and the north bridge chip is below. The south bridge chip is generally far away from the CPU, often exposed next to the PCI slot, and is relatively large; the north bridge chip is a system control chip, which is mainly responsible for data exchange between the CPU, memory, and graphics card, and is composed of the south bridge chip. The chipset plays a leading role and controls some high-speed devices, such as CPU, Host bus, etc. What CPU the motherboard supports, how many graphics cards it supports for AGP, and what frequency of memory it supports are all determined by the Northbridge chip. The north bridge chip often has a higher operating frequency, so the heat generation is quite high. The south bridge chip mainly determines the functions of the motherboard. The various interfaces on the motherboard, PS/2 mouse control, USB control, PCI bus IDE and other chips on the motherboard ( Such as integrated sound card, integrated RAID card, integrated network card, etc.) are all controlled by the South Bridge chip. With the continuous development of the PC architecture, the functions of the north bridge are now gradually included by the CPU, and its structure is continuously simplified and even no longer exists in the chipset .
BIOS chip
BIOS (Basic Input/ Output System, basic input output system), the full name is ROM-BIOS, is the abbreviation of read-only memory basic input/output system. BIOS is actually a set of programs that are solidified into the computer to provide the computer with the lowest level and most direct hardware control. It is the hub between the software program and the hardware device. In layman's terms, the BIOS is between the hardware and the software program. A "converter" or interface is responsible for solving the immediate requirements of the hardware, and executes it according to the operating requirements of the software on the hardware. From a functional point of view, BIOS mainly includes two parts:
(1) Self-check and initialization
Self-check and initialization are responsible for starting the computer, there are 3 parts specifically :
Power on self test (POST) is used to test the hardware when the computer is just turned on to check whether the computer is in good condition. Usually a complete POST self-test will include testing the CPU, 640K basic memory, 1M or more extended memory, ROM, motherboard, CMOS memory, serial and parallel ports, graphics card, soft and hard disk subsystem, and keyboard. Once problems are found in the self-test , The system will give a prompt message or buzzer warning .
Initialization, including creating interrupt vectors, setting registers, initializing and testing some external devices, etc., a very important part of which is the BIOS settings, mainly some parameters for the hardware settings, when the computer starts, it will read these parameters, and The actual hardware settings are compared. If they do not match, it will affect the startup of the system.
Bootloader, used to boot DOS or other operating systems. BIOS first reads the boot record from the start sector of the floppy disk or hard disk. If it is not found, it will show that there is no boot device. If it finds the boot record, it will transfer the control of the computer to the boot record, and the boot record will transfer the operating system Load the computer, after the computer starts successfully, this part of the BIOS task is completed.
(2) Program service processing and hardware interrupt processing
These two parts are two independent contents, but they are closely related in use. Program service handlers mainly serve applications and operating systems. These services are mainly related to input and output devices , such as reading disks and outputting files to printers. In order to complete these operations, B1OS must directly deal with the computer's I/O devices. It sends commands through ports, transmits data to various external devices and receives data from them, so that the program can be separated from specific hardware operations, and hardware interrupt processing Then the PC hardware requirements are handled separately, so the two parts are software and hardware services respectively, and they are combined to make the computer system run normally.
The service function of BIOS is realized by calling interrupt service program . These services are divided into many groups, and each group has a special interrupt. For example, for video services, the interrupt number is 10H; for screen printing, the interrupt number is 05H; for disk and serial port services, the interrupt number is 14H, etc. Each group is subdivided into different service numbers according to specific functions. What peripherals and operations the application needs to use only need to be explained in the program with the corresponding instructions, without direct control. Because CMOS and BIOS are closely related to the computer system settings, it is easy to confuse the two. Fundamentally speaking, CMOS RAM is the place where system parameters are stored, and the system setup program in BIOS is the means to complete parameter settings. Therefore, the accurate statement should be to set the CMOS parameters through the BIOS setup program.
