Handling Skills for Common Problems of Computer Hardware
I. BIOS Functions
Functionally, BIOS is divided into three parts:
1. Self-inspection and initialization procedures;
2. Hardware interrupt handling;
3. Program service request.
Let's have a detailed understanding of the functions of its various parts:
(a) self-inspection and initialization
This part is responsible for starting the computer. It has three parts. The first part is used to detect the hardware part when the computer is just powered on. It is also called power-on self-test (POST). Its function is to check whether the computer is in good condition, such as whether there is any fault in the memory, etc. The second part is initialization, which includes creating interrupt vectors, setting registers, initializing and detecting some external devices, etc. The most important part is BIOS setting, which mainly refers to some parameters of hardware setting. When the computer starts up, these parameters will be read and compared with the actual hardware setting. If they do not conform, the startup of the system will be affected.
The last part is the boot program, whose function is to boot DOS or other operating systems. BIOS first reads the boot record from the starting sector of the floppy disk or hard disk. If it is not found, it will show that there is no boot device on the display. If it is found, it will transfer the control of the computer to the boot record. The boot record will load the operating system into the computer. After the computer starts successfully, this part of BIOS tasks will be 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 application programs 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, BIOS must deal directly with the I/O devices of the computer. It issues commands through the ports, transmits data to various external devices and receives data from them, so that the program can be separated from specific hardware operations, while hardware interrupt processing processes the hardware requirements of the PC respectively. Therefore, these two parts serve software and hardware respectively, and are combined together 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, each group has a special interrupt. For example, video service, the interrupt number is 10H；; Screen printing, interrupt number is 05H；; Disk and serial port service, interrupt 14H, etc. Each group is subdivided into different service numbers according to specific functions. What peripherals and operations the application program needs to use only need to be explained with corresponding instructions in the program, without direct control.
<18px><18px>II. Types of BIOS18px>
Because BIOS directly deals with system hardware resources, it is always aimed at a certain type of hardware system, and each hardware system is different, so there are different kinds of BIOS. With the development of hardware technology, different versions of the same BIOS have appeared successively. The new version of BIOS is more powerful than the old version.
At present, BIOS is divided into three types: AWARD, AMI and PHOENIX. The manufacturer's mark can be seen on the chip. Among them, PHOENIX and AWARD have merged (AWARD has acquired PHOENIX). AWARD BIOS is generally used on motherboards, although it is labeled PHOENIX-AWARD. The BIOS of a brand name machine is generally PHOENIX's BIOS. However, for INTEL's original motherboard, its BIOS is specially customized by PHOENIX. The general notebook is the original phoenix style, while the desktop is the award style (to brush BIOS, it is better to confirm your motherboard brand and model first)
Let's move on to the topic you want to know most.
1 Short: The system starts normally.
2 short: general error (enter CMOS Setup and reset incorrect options)
1 long and 1 short: RAM or motherboard goes wrong (try to replace it with another memory; if it still fails, the motherboard will have to be replaced)
1 long and 2 short: display or display card error.
1 long and 3 short: keyboard controller error (check motherboard)
1 Long 9 Short: Main Board Flash RAM or EPROM Error, BIOS Damage (Try Replacing Flash RAM)
Constantly ringing (long sound): the memory module is not tightly inserted or damaged (if the memory module is not valid after re-insertion, only the memory module can be replaced)
Keep ringing: the power supply and monitor are not connected to the video card (check all plugs)
Repeated short ring: there is a problem with the power supply.
No sound, no display: there is a problem with the power supply.
Phoenix BIOS :
1 Short: The system starts normally.
1 short, 1 short, 1 short: initialization of system power-on self-test failed.
1 short 1 short 2 short: motherboard error.
1 Short 1 Short 3 Short: CMOS or Battery Error.
1 short 1 short 4 short: ROM BIOS verification failed.
1 short 2 short 1 short: system clock error.
1 short 2 short 2 short: DMA initialization failed.
1 Short 2 Short 3 Short: DMA Page Register Error.
1 short 3 short 1 short: RAM refresh error.
1 Short 3 Short 2 Short: Basic Memory Error.
1 Short 3 Short 3 Short: Basic Memory Error.
1 short 4 short 1 short: basic memory address line error.
1 short 4 short 2 short: basic memory check error.
1 short 4 short 3 short: EISA sequencer error.
1 short 4 short 4 short: EASA NMI port error.
2 short, 1 short, 2 short to 2 short, 4 short, 4 short (i.e. a combination of all sounds starting with 2 short): basic memory error.
3 Short 1 Short 1 Short: Error from DMA Register.
3 Short 1 Short 2 Short: Main DMA Register Error.
3 short 1 short 3 short: main interrupt processing register error.
3 Short 1 Short 4 Short: Error from Interrupt Processing Register.
3 short 2 short 4 short: keyboard controller error.
3 Short 3 Short 4 Short: Memory Error of Display Card.
3 short 4 short 2 short: display error.
3 Short, 4 Short, 3 Short: No Display Read Only Memory Found.
4 Short 2 Short 1 Short: Clock Error.
4 Short 2 Short 2 Short: Shutdown Error.
4 short 2 short 3 short: A20 gate error.
4 Short 2 Short 4 Short: Protection Mode Interrupt Error.
4 Short 3 Short 1 Short: Memory Error.
4 short 3 short 3 short: clock 2 wrong.
4 Short 3 Short 4 Short: Real Time Clock Error.
4 short 4 short 1 short: serial port error.
4 Short 4 Short 2 Short: Parallel Port Error.
4 short 4 short 3 short: digital coprocessor error.
1 Short: Memory refresh failed. (Replace Memory Module)
2 short: memory ECC check error is commonly referred to as memory parity error (can enter CMOS setting,
Turn off the memory parity parity check option and set it to Disabled. But generally speaking,
Memory chips have parity check and parity check is turned on in CMOS setting, which is stable for microcomputer system
Qualitative analysis is beneficial. )
3 short: system basic memory (64KB first) check failed (replace memory)
4 short: system clock error. (Repair or Replace Motherboard)
5 short: CpU error, but it is not necessarily all the fault of CpU itself, it may also be CPU socket or somewhere else
Problem, if this CpU is normal on other motherboards, the error is definitely the motherboard.<16px>6 short: keyboard controller error (if the keyboard is not plugged in, then easy to do, just plug in; If the keyboard is connected16px>
If you receive a normal but error message, you may as well try a good keyboard. Otherwise, it is keyboard control.
7 short: system real mode error, cannot switch to protection mode (also belongs to motherboard fault)
8 Short: Display Memory Read/Write Error The memory chip on the video card may be damaged (if the memory chip is pluggable
, as long as find out the bad piece and replace it, otherwise the video card needs repair or replacement).
9 Short: ROM bIOS Check Error (Try to change a good bIOS of the same type. If it proves that there is something wrong with the BIOS,
11 Short Cache Error.
1 Long 3 Short: Memory Error.
1 long and 8 short: display test error.
1 Short: The system is normal.
2 Short: The system power-on self-test (POST) failed.
1 long: power supply error, if there is no display, it is a display card error.
1 long 1 short: motherboard error.
1 long 2 short: graphics card error.
1 short 1 short 1 short: power supply error.
3 long and 1 short: keyboard error.