BIOS (Basic Input/Output System) is a program recorded on a chip on the motherboard, in particular, EEPROM (Electrically Erasable Programmable Read-Only Memory) type.
What is BIOS in Computer Technologies?
BIOS is an application that finds, recognizes, and configures all the devices on a Motherboard (MB) needed to load the Operating System into RAM. It provides low-level communication, booting, and system hardware configuration, at least operating the keyboard and providing primary output (standard beeps from the computer speaker) during startup.
BIOS is usually written in Assembly Language. The term first appeared in the CP/M operating system and describes the part of CP/M that is executed during startup and directly connected to the hardware. Most versions of MS-DOS have a file called IBMBIO.COM or IO.SYS, which is similar to the CP/M BIOS.
It is a basic input/output system that is typically unnoticed by computer end users. It is responsible for finding and loading the operating system into RAM. It has hardware and software components. The latter provides a general text interface (SETUP) that allows you to configure various hardware options, such as the clock installed on the PC or which storage devices the operating system will start from.
It manages at least the computer keyboard. It even provides a fundamental output in the form of sounds from the internal speaker on the motherboard when there is an error, such as a device that has failed or needs to be connected.
Technicians use these error messages to find solutions when assembling or repairing equipment. This is located in the EEPROM memory. It is a type of firmware program.
It is a critical piece of hardware that is partially configurable and controls the flow of information between the computer data bus, the operating system, and other peripherals. It also includes the configuration of fundamental aspects of the machine.
The BIOS system of a standard computer actually performs four independent functions:
- Hardware Inventory and Test Program (Power On Self Test).
- The initial software loading process.
- Initialization of hardware devices that require it; loading of some essential software; and starting the operating system.
- Support for specific system hardware devices.
Access
To access the BIOS configuration program, usually called Setup, you need to press one or more keys during the computer startup.
In general, it is usually the Delete key. However, this varies depending on the type of board and laptop. Other keys used are F1, Esc, F2, or a combination of keys. To understand it exactly, it will be enough to consult your motherboard manual or pay attention to the first boot screen. Usually, a message appears at the bottom. For example, press DEL to enter Setup.
The BIOS program is usually in perfect English. And some terms are not really simple. If you do not know what you are doing, consult the manual or an expert. Otherwise, you will encounter problems. Although they have different names, some sections are common to all types of BIOS. A classification can be:
- Basic parameter configuration – Standard CMOS Setup.
- BIOS Options – BIOS Features, Advanced Setup.
- Advanced configuration and chipset – Chipset features.
- Password, peripherals, hard drives.
BIOS Types
Usually, this software is recorded in a read-only memory chip ROM located on the motherboard, called memory ROM BIOS. This guarantees that it will not be lost when the system is turned off and that its performance will not depend on the presence or proper operation of any disk, so it will always be available.
The latter is essential because it allows the initial startup of the equipment without requiring any external resources. From the early days of computer life, ROM-BIOS caused problems with existing hardware because technical developments were constant. It was they who had to increase the capabilities of the disk and the devices connected to the equipment.
This required new BIOSes, which were necessary to replace the motherboard or at least to replace the integrated one that contained the ROM BIOS in later models. To solve the problem, rewritable memories such as EPROM (Erasable programmable read-only memory) and EEPROM (Electrically erasable programmable read-only memory) were introduced.
Currently, a type of non-volatile flash memory (Flash BIOS) is used. It can be rewritten without using any special erasing or recording device, allowing it to be updated very conveniently.
Usually, it is only necessary to download the appropriate version from the Internet (usually from the motherboard manufacturer’s website) and follow the instructions in the program.
BIOS is constantly used in normal PC operations and accesses RAM faster than ROM. Many manufacturers require that the contents of the BIOS ROM be copied to RAM as part of the boot process. First, this is known as shadowing, which speeds up system performance. The BIOS version loaded into RAM is called shadow BIOS.
Naturally, this requires the realignment of the interrupt vectors. So, they point to new locations in RAM. The most modern BIOS is called PnP BIOS or PnP-compatible BIOS. This means that they aim to address Microsoft’s “Plug and Play” PnP standard.
IRQ is a technology that allows any connected hardware device to identify it and sign the necessary resources without conflicting with the rest. Before this technology, adding new devices was a real headache, given the resource shortages that PC designers expected—for example, known IRQs and port address conflicts.
Firmware on Adapter Cards
A system BIOS may contain several chips that contain the BIOS firmware. In addition to the boot, BIOS is found on the hard drive and motherboard.
Manufacturer Market
The vast majority of PC motherboard vendors outsource the production of the BIOS and a suite of tools to third parties.
These are known as independent vendors or IBVs. Motherboard manufacturers then customize this BIOS to their hardware. Therefore, updates are usually obtained directly from the motherboard manufacturer.
The manufacturer may release firmware updates through their website, but poor compatibility with the hardware can cause a bug to spread throughout the motherboard, rendering it completely useless. The major vendors are American Megatrends (AMI), General Software, Insyde Software, and Phoenix Technologies (which acquired Award Software International in 1998).
TolgaBagci
Hi, I'm Tolga, a computer expert with 20 years of experience. I help fix computer issues with things like hardware, systems, networks, virtualization, servers, and operating systems. Check out my website for helpful info, and feel free to ask me anything. Keep yourself in the loop about the newest technologies!
