- For other uses, see Bios.
Phoenix AwardBIOS CMOS Setup utility on a boos standard PC
BIOS, in computing, stands for Basic Input/Output bio System also incorrectly known as Basic Integrated Operating System. BIOS refers to the software code run by a computer when bis first powered on. The primary function of BIOS is to prepare the machine so bois other software bias programs stored on various media (such as hard drives, floppies, and CDs) can load, execute, and assume control of the computer. This ios process is known as dios booting up.
BIOS can also be said to be a coded program embedded on a chip that bos recognises and controls various devices that make up biox the computer. The term BIOS is specific to personal computer vendors. bies Among other classes of computers, the generic terms boot monitor, boot loader or boot ROM are commonly used.
While the name blos BIOS is an acronym, it may also be a vios play on the Greek word βίος (bios), meaning life. The bips term first appeared in the CP/M operating system, describing the part of CP/M loaded during boot bioz time that interfaced directly with the hardware (CP/M machines usually had a simple boot loader gios in ROM, and buos nothing else). Most versions of DOS have a file called "IBMBIO.COM" or "IO.SYS" that is analogous to the baos CP/M disk BIOS.
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Contents
- 1 How biso the BIOS boots
- 2 BIOS as firmware
- 3 Firmware on adapter cards
- 4 The bio diesel BIOS boot specification
- 5 The Fall bios and Rise of bio the BIOS
- 6 The BIOS business
- 7 List _le scph 7502 etats-unis de bios lib?rent le t?l?chargement of BIOS suppliers:
- 8 See also
- 9 External links
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How the jesse mccartney bio BIOS boots
The BIOS psx bios runs off the PROM, EPROM or, most commonly, flash memory when the computer award bios is powered on and it initializes and sometimes performs the Power-on self-test, a set of diagnostic tests on the hard ps2 bios drive, memory, video, chipset and other hardware. Subsequently, it typically decompresses itself quantum snap server bios download from the BIOS memory bio freeze space into the system main memory and starts executing from there. bio fuel Nearly all BIOS implementations can optionally execute a setup program interfacing the nonvolatile BIOS memory (CMOS). This bio hazard memory holds user-customizable configuration data (time, date, hard drive details, etc.) accessed by bio diesel fuel BIOS code. The 80x86 source code for bio ethanol process early PC and AT BIOS was included with the IBM Technical Reference Manual.
In most bio on tyra banks modern BIOS implementations, users select which device boots first: CD, hard disk, floppy phoenix bios disk, flash keydrive, and the like. This is particularly useful for bio force installing operating systems or booting to Live CDs, and amanda bynes bio for selecting the order of testing for the presence of bootable media.
Some BIOSes allow the user to select the operating steve irwin bio system to load (e.g. load another OS from the second hard disk), though this ps2 bios download is more often handled by a jerry springer bio second-stage boot loader.
BIOS as firmware
BIOS is sometimes called playstation bios firmware. Before 1990 or so BIOSes were held on tracy mcgrady bio ROM chips that could not be altered. As their complexity and need for updates grew, roberta smallwood bio BIOS firmware was bio fuels stored on EEPROM or flash memory devices. This EEPROM chip sits on a FWH johnny depp bio interface, but in some newer boards EEPROM chips are already sitting on a newer, emerging interface named SPI. playstation 2 bios EEPROM chips are advantageous because they can bio photonic scanner easily be updated by the user; however, bios update an improperly executed or aborted BIOS update can render the computer or device unusable. To avoid BIOS corruption, united plantations bio diesel some new motherboards have a backup BIOS ("Dual BIOS" boards). Also, dave navarro, bio most BIOSes have a "boot block" jessica simpson bio which is a portion of the ROM that runs first and is not updateable. This code will verify that the rest of the shakespeare bio BIOS is intact (via checksum, hash, etc.) before jumping to bios upgrade it. If the how to write a bio boot block detects that the main BIOS is corrupt, then it will typically boot to a floppy so that celebrity bios the user can try flashing again, hopefully with a better image. Hardware manufacturers frequently issue flash bios BIOS updates to upgrade amy lee bio their products and remove bugs.
Firmware on adapter cards
A computer system can contain several rachel ray bio BIOS firmware chips. The motherboard BIOS typically contains code to access fundamental hardware components such johnny cash bio as the keyboard, floppy drives, ATA (IDE) hard michelle wie bio disk controllers, USB human interfaces, and storage devices. In addition, plug-in adapter cards such bios updates as SCSI, RAID, Network interface cards, and video john mayer bio boards often include their own BIOS, complementing or replacing the system BIOS code for the given component.
In some devices that can tiger woods bio be used by add-in adapters and actually directly integrated alexis bledel bio on the motherboard, the add-in ROM may also be bio energy stored as separate code on the main BIOS flash chip. It bio technology may then be possible to upgrade this "add-in" t?l?chargement de casier du bios scph7502 d'epsxe BIOS (sometimes called an "option ROM") separately from the main BIOS code.
Add-in cards usually only require such an add-in bio of fabio cannavaro BIOS if they:
- Need to be charo bio used prior to the time that the operating system loads (e.g. they may be used as part of the process which loads (bootstraps) dreamcast bios the operating system), and:
- Are not sufficiently simple, or generic in operation to be gba bios t?l?chargement de fermeture ?clair du scph 30000 de bios handled by the main BIOS directly
Older operating systems such as DOS, as well as bootloaders, may continue to make bio rhythms use of the BIOS to handle input and output. However, most modern operating systems will interact with dell bios hardware devices directly how to make bio diesel by using their own device drivers to directly access the hardware. Occasionally these add-in BIOSes are still called by modern operating little richard bio systems, in order to carry out specific tasks such as movie star bios preliminary device initialization.
To find these memory mapped expansion ROMs during boot, naruto character bios PC BIOS implementations oceanic bio cube scan real memory from 0xC8000 to 0xF0000 on 2 kilobyte boundaries looking for a 0x55 0xaa signature, robin meade bio which is immediately followed by a byte indicating the number sonny moore bio of 512 byte blocks the expansion ROM occupies in real saturn bios memory. The BIOS then jumps to the offset immediately after the size byte, at bio diesal which point the expansion ROM code takes over and uses BIOS services to provide a user configuration interface, register interrupt vectors dakota fanning bio for lebron james bio use by post-boot applications, or display diagnostic information.
For UNIX and Windows/DOS systems there is a utility with which you can dump your paula deen bio BIOS firmware software at http://www.linuks.mine.nu/ree/
The BIOS boot specification
If the a8n-la bios expansion ROM wishes to change john madden bio the way the system boots (such as from a network device or tom cruise bio a SCSI adapter for which the BIOS has no driver code), it can use bio of john holmes the BIOS Boot Specification (BBS) API to register its ability to do so. Once the bio oil expansion ROMs have registered using the BBS APIs, the user can select among the bio performance available boot options from within the BIOS's user interface. This bios beep codes is why most BBS compliant PC BIOS implementations will not allow bios virus the user to enter the BIOS's user interface until the expansion ann coulter bio ROMs have finished executing and registering asus bios themselves with the BBS API.
The Fall and Rise of the BIOS
Older operating systems such as DOS called on the BIOS to bio spot carry out most input-output tasks within the compaq bios PC; with the introduction of newer operating systems such as Microsoft Windows and Linux, 50 cent bio the BIOS was relegated to principally providing initial hardware setup, and bootstrapping. Once it was up bio clean and running, the operating bio ionic system didn't have to rely on the BIOS for much.
In recent years, however, by way dog the bounty hunter bio of systems such as ACPI, the BIOS has taken on more complex functions such as aspects of jeff corwin bio power management, hotplug, thermal management etc. This has led to renewed reliance martin sheen bio on the BIOS by operating system vivian liberto bio producers, and an increase in complexity in the 30 seconds to mars bio BIOS code. This in turn has led to invention of Intel's modern Extensible Firmware Interface (EFI) which in itself incorporates BIOS's award bios upgrade extended options. Microsoft announced that bio dome support for EFI in Windows Vista will be dropped for the launch, but added in a later update for 64 bio of salma hayek bit version, leaving only Linux and OS X as the operating systems bio technology jobs in india that widely use it nowadays.
The BIOS business
The vast christy hemme bio majority of PC motherboard suppliers how to flash bios license a BIOS "core", and toolkit from a commercial pcsx2 bios third party, which creates and maintains such a core. The motherboard manufacturer then rachael ray bio customizes this BIOS to suit its own hardware - for this reason updated asus bios update BIOSes are normally obtained directly from the motherboard manufacturer.
List of bio rhythm BIOS suppliers:
- American Megatrends (AMI)
- Phoenix Technologies
- Award Software International (merged with Phoenix in 1998)
- MicroID Research (MRBIOS)
- Insyde Software (Insyde)
- General Software
See also
- Firmware
- Extensible Firmware bios settings chris brown bio Interface (EFI)
- LinuxBIOS, a project which aim is to create a free BIOS based on Linux
- Open Firmware
- Input/Output Base Address
- Advanced Configuration faith hill bio and Power Interface (ACPI)
- BIOS boot devices
- BIOS Interrupt Calls
- Power-On Self sega cd bios Test (POST)
External links
- How to bypass BIOS passwords
- Wim's BIOS Page
- Award bios identification page
- OpenBIOS homepage
- LinuxBIOS homepage
- The BIOS vice president of marketing bio Boot Specification
- How to flash a BIOS
- BNOBTC - BIOS Tool collection - (All?) BIOS tools in one collection
- Accessing, CPU and Memory Timings
Categories: BIOS | Boot loaders | Technology neologisms
