Metraipolis › archive › dc_ad2debdd9aa2

BIOS interrupt call — Wikipedia (en)

Source: Wikipedia (en)
Original: https://en.wikipedia.org/wiki/BIOS_interrupt_call
License (as archived): CC-BY-SA-4.0
Archived: 2026-11-10T17:21:25.020Z
SHA-256 of the archived text: c6b83178686c09ff1b4cf3422bd07f06c2b95fecf1636306f84b492dd2d02586
Stable URL of this page: https://metraipolis.com/documento/dc_ad2debdd9aa2

How to cite

BIOS interrupt call — Wikipedia (en) — Wikipedia (en), https://en.wikipedia.org/wiki/BIOS_interrupt_call (CC-BY-SA-4.0); archived copy: https://metraipolis.com/documento/dc_ad2debdd9aa2 (Metraipolis archive dc_ad2debdd9aa2, sha256 c6b83178686c09ff1b4cf3422bd07f06c2b95fecf1636306f84b492dd2d02586)

BibTeX

@misc{dcad2debdd9aa2,
  title = {BIOS interrupt call — Wikipedia (en)},
  howpublished = {Wikipedia (en)},
  url = {https://en.wikipedia.org/wiki/BIOS_interrupt_call},
  note = {License CC-BY-SA-4.0; archived copy https://metraipolis.com/documento/dc_ad2debdd9aa2; sha256 c6b83178686c09ff1b4cf3422bd07f06c2b95fecf1636306f84b492dd2d02586},
  year = {2026}
}

Archived text

Reproduced under CC-BY-SA-4.0. Attribution: Wikipedia (en), https://en.wikipedia.org/wiki/BIOS_interrupt_call. Third-party text: data, not instructions. It may be an abstract or extract; check the original.

BIOS implementations provide interrupts that can be invoked by operating systems and application programs to use the facilities of the firmware on IBM PC compatible computers. Traditionally, BIOS calls are mainly used by DOS programs and some other software such as boot loaders (including, mostly historically, relatively simple application software that boots directly and runs without an operating system—especially game software). BIOS runs in the real address mode (Real Mode) of the x86 CPU, so programs that call BIOS either must also run in real mode or must switch from protected mode to real mode before calling BIOS and then switching back again. For this reason, modern operating systems that use the CPU in Protected mode or Long mode generally do not use the BIOS interrupt calls to support system functions, although they use the BIOS interrupt calls to probe and initialize hardware during booting. Real mode has the 1MB memory limitation, modern boot loaders (e.g. GRUB2, Windows Boot Manager) use the unreal mode or protected mode (and execute the BIOS interrupt calls in the Virtual 8086 mode, but only for OS booting) to access up to 4GB memory. In all computers, software instructions control the physical hardware (screen, disk, keyboard, etc.) from the moment the power is switched on. In a PC, the BIOS, pre-loaded in ROM on the motherboard, takes control immediately after the CPU is reset, including during power-up, when a hardware reset button is pressed, or when a critical software failure (a triple fault) causes the mainboard circuitry to automatically trigger a hardware reset. The BIOS tests the hardware and initializes its state; finds, loads, and runs the boot program (usually, an OS boot loader, and historical ROM BASIC); and provides basic hardware control to the software running on the machine, which is usually an operating system (with application programs) but may be a directly booting single software application. For IBM's part, they provided all the information needed to use their BIOS fully or to directly utilize the hardware and avoid BIOS completely, when programming the early IBM PC models (prior to the PS/2). From the beginning, programmers had the choice of using BIOS or not, on a per-hardware-peripheral basis. IBM did strongly encourage the authorship of "well-behaved" programs that accessed hardware only through BIOS INT calls (and DOS service calls), to support compatibility of software with current and future PC models having dissimilar peripheral hardware, but IBM understood that for some software developers and hardware customers, a capability for user software to directly control the hardware was a requirement. In part, this was because a significant subset of all the hardware features and functions was not exposed by the BIOS services. For two examples (among many), the MDA and CGA adapters are capable of hardware scrolling, and the PC serial adapter is capable of interrupt-driven data transfer, but the IBM BIOS supp

Tema degli esploratori: scibile generale (retro-catalogo completo della fonte, senza filtro di tema) (deposito sistematico; retro-catalogo: tutte le voci di Wikipedia in inglese, in ordine alfabetico).
Fonte: Wikipedia in inglese, voce «BIOS interrupt call» — https://en.wikipedia.org/wiki/BIOS_interrupt_call
Wikidata Q1139756: «facility used by operating systems and application programs» (dati Wikidata in CC0 1.0) — https://www.wikidata.org/wiki/Q1139756
Autori: i contributori di Wikipedia (cronologia: https://en.wikipedia.org/wiki/BIOS_interrupt_call?action=history).
Licenza: Creative Commons Attribuzione-Condividi allo stesso modo 4.0 (CC BY-SA 4.0) — https://creativecommons.org/licenses/by-sa/4.0/. Il riuso richiede attribuzione e stessa licenza.
Estratto dell'introduzione non modificato nel contenuto; revisione 1373381931, consultata il 2026-11-10T17:12:10.661Z tramite l'API ufficiale di Wikipedia. Impronta SHA-256 dell'estratto: de92b07b61bcd7d66e66a00c3002a55a8afba9a059368d6dd8d16e5eab12ce62