BIOS is a firmware code that is usually embedded in the personal computer. It is the first thing that is executed when the computer is turned on. It normally enables the computer to function normally and enables the operating system to function properly. In computer terms, BIOS is known as the Basic Input/output System or BIOS, and is also referred to as the System BIOS, ROM BIOS, PM BIOS or Peripheral BIOS. The purpose of having a BIOS is to control input and output devices during computer operation by switching off or starting them depending on the current status.
The BIOS chips are usually embedded in the motherboards or installed on the computers by the manufacturers. The purpose of having a BIOS in the computer is to control the operating system and hardware. The BIOS is usually flash based and needs to be read by the computer BIOS chip during start up. Once the BIOS has been detected, it will switch off the machine, making the operating system to load again. If the system does not have a working BIOS chip, the operating system will refuse to start without it.
Since the purpose of having a BIOS in the computer is to enable the machine to turn on automatically, all the machines must have a working BIOS. Usually, a BIOS is vulnerable to viruses and can get corrupted and reset, causing the BIOS to work in the wrong way. To avoid this, the manufacturers provide a utility called BIOS Repair, which is able to fix most BIOS related issues. If you want to do some tweaking with the BIOS, you should use BIOS-Fix.
The BIOS chip has two components: the BIOS ROM and the PROM. The BIOS ROM is the one responsible for performing basic operations like reading out of the input devices and setting the state of the hardware. In the case of the BIOS-GCMA, the chips in the motherboard have extra instructions that are ignored by the hardware, leading to the program to be executed twice. This may result in two different programs using the same CPU and therefore two different programs running on the same processor. This is not seen with the BIOS-ESS and the EESS.
The BIOS, when supported by the hardware, is used to determine whether to load the boot code from memory or from the hard drive. If your PC has a built-in boot manager, you will not need to use the BIOS. Otherwise, you have to allow the user to select the appropriate mode for the machine. The bootup process requires the entry of a random number, BIOS’s PROM and an interrupt during which the system prepares for the read-write access to the disks.
If your PC uses a PCI bus, you must include AGP controller in your BIOS definition. It is used to load the OS (Operating System) and for turning on/off the PC’s peripheral devices. Without this device, the PC will only boot up from the hard disk and it will not turn on. You can also enable/ Disable the boot process through BIOS by including a boot register. The boot register is a stub that returns a binary value after the operating system has started up.
If you have a non-functional BIOS due to a defective or lost device drivers, you can still retrieve your BIOS data by using the BIOS recovery utility. For some recent PCs, the BIOS can be accessed by accessing BIOS chips found on the motherboard. If your PC refuses to start, you may need to replace the BIOS chip that is missing. Similarly, if you encounter BIOS hang during operation, you should check whether the various software components are properly installed and updated.
Some operating systems such as Windows XP run the BIOS by starting up in Safe Mode but most modern Windows platforms starting with Windows Vista utilize the BIOS to execute the boot process. To test your BIOS’s ability to reset to the default boot mode, you can use a service tool called F POST or force BIOS. If you are having trouble in starting your PC or your device is not responding in the usual way, you should consider contacting your computer’s manufacturer for more information about your BIOS.