The system basic input / output or BIOS (Basic Input-Output System) is a code of software that locates and loads the operating system into RAM, is a very basic software installed on the motherboard that allows it to perform its duties. Provides low-level communication, operation and configuration of system hardware that at least handles the keyboard and provides basic output (standard beeps from the speaker of the computer if there are failures) during startup. The BIOS usually written in assembly language. The term first appeared in the BIOS operating system CP / M, and describes the part of CP / M which was executed during the boot and was attached directly to the hardware (the machines from CP / M usually had a simple loader in ROM bootable and nothing more). Most versions of MS-DOS have a file called "IBMBIO.COM" or "IO.SYS" that is similar to CP / M BIOS.
This basic system is generally started on all computers with three different keys can be: F2, F10 or Delete One of these keys must be pressed during the loading of the computer
In the early years of PC operating systems (like DOS), the BIOS still remained active after startup and operation of the operating system. Access to devices such as floppy and hard drives were made through the BIOS. However, most modern operating systems OS perform these tasks by themselves without having to call the BIOS routines.
When you turn on the computer, the BIOS is loaded automatically in the main memory and executed by the processor from there (although in some cases the processor executes the BIOS reading directly from the ROM that contains it), when conducting a routine check and initialization of the components in the computer, through a process called POST (Power On Self Test). At the end of this phase searches for the startup code of the operating system (bootstrap) in some of the secondary memory devices present, loads it into memory and transfers control of the computer to it.
Can be summarized by saying that the BIOS is the firmware in computers and IBM PC compatibles, which contains the basic instructions for the operation to include the same basic routines to control the input and output devices. This is stored in a memory chip or flash ROM located on the motherboard of the computer. This chip is often referred to as female in the "BIOS", as it refers to a memory (female) specific, but refer to the contents, do the right thing is the masculine "BIOS", since we are dealing with a (male) Input / Output.
The main shortcoming of this component is to remain fairly faithful toits structure lucia early 80's. Even the most modern microprocessors, 64-bit dual-core work in 16-bit real mode when turning on the PC, emulating the Intel 8086 processor in 1978. In these circumstances, the main memory that goes beyond the first MB can not be used during startup of the machine. Also, video cards, expansion and, in general, the devices should remain available in this process must include a readable memory of 128 kbytes.
Another important disadvantage is that still programmed in assembly language, but most optimal performance in more complex to develop and maintain. Yet, it has added new features to the BIOS that have contributed decisively to increase its complexity.
This basic system is generally started on all computers with three different keys can be: F2, F10 or Delete One of these keys must be pressed during the loading of the computer
In the early years of PC operating systems (like DOS), the BIOS still remained active after startup and operation of the operating system. Access to devices such as floppy and hard drives were made through the BIOS. However, most modern operating systems OS perform these tasks by themselves without having to call the BIOS routines.
When you turn on the computer, the BIOS is loaded automatically in the main memory and executed by the processor from there (although in some cases the processor executes the BIOS reading directly from the ROM that contains it), when conducting a routine check and initialization of the components in the computer, through a process called POST (Power On Self Test). At the end of this phase searches for the startup code of the operating system (bootstrap) in some of the secondary memory devices present, loads it into memory and transfers control of the computer to it.
Can be summarized by saying that the BIOS is the firmware in computers and IBM PC compatibles, which contains the basic instructions for the operation to include the same basic routines to control the input and output devices. This is stored in a memory chip or flash ROM located on the motherboard of the computer. This chip is often referred to as female in the "BIOS", as it refers to a memory (female) specific, but refer to the contents, do the right thing is the masculine "BIOS", since we are dealing with a (male) Input / Output.
The main shortcoming of this component is to remain fairly faithful toits structure lucia early 80's. Even the most modern microprocessors, 64-bit dual-core work in 16-bit real mode when turning on the PC, emulating the Intel 8086 processor in 1978. In these circumstances, the main memory that goes beyond the first MB can not be used during startup of the machine. Also, video cards, expansion and, in general, the devices should remain available in this process must include a readable memory of 128 kbytes.
Another important disadvantage is that still programmed in assembly language, but most optimal performance in more complex to develop and maintain. Yet, it has added new features to the BIOS that have contributed decisively to increase its complexity.
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