BIOS

A sarrafa kwamfuta, **BIOS** ( /b aɪ ɒ s, - oʊ s /, BY -oss, - ⁠ ohss ; wani gajeren bayani ne na **Basic Input / Output System** wanda kuma aka fi sani da suna **System BIOS**, **ROM BIOS** ko **PC BIOS** ) ana amfani da firmware ne don aiwatar da farawar kayan masarufi yayin aiwatar da *booting* (farawa-kunnawa), da kuma samar da sabis na lokaci, don tsarin aiki da shirye-shirye.  BIOS *firmware* ta kasance an riga an girka ta akan kwamiti na komputa na sirri, kuma shine software na farko da zata fara aiki yayin kunna ta. Sunan ya samo asali ne daga Asalin *Input/Output System* wanda aka yi amfani dashi a cikin tsarin aiki na CP/M a shekarar 1975. BIOS asalin mallakar IBM PC ne wasu kamfanoni suka sake kera shi (kamar su *Phoenix Technologies* ) suna neman ƙirƙirar tsarin da zai dace.  A dubawa na cewa asalin tsarin hidima a matsayin *zahiri shine* misali.

BIOS a cikin PCs na zamani suna farawa da kuma gwada abubuwan haɗin kayan aikin, kuma suna loda mai ɗora kaya daga na'urar adana kayan aiki wanda zai fara tsarin aiki. A cikin zamanin DOS, BIOS ta bayar da BIOS ta katse kira don maɓallin keyboard, nuni, adanawa, da sauran kayan shigarwa / fitarwa (I / O) waɗanda ke daidaita daidaito ga shirye-shiryen aikace-aikace da tsarin aiki. Sabbin tsarin aiki na kwanan nan basa amfani da BIOS na katse kira bayan farawa. 

Yawancin aikace-aikacen BIOS an tsara su musamman don aiki tare da takamaiman kwamfuta ko samfurin katako, ta hanyar hulɗa tare da na'urori daban-daban waɗanda suka dace da tsarin kwakwalwar kwamfuta . Asali, an adana firmware na BIOS a cikin guntu ta ROM akan uwar komputa. A cikin tsarin kwamfuta na zamani, ana adana abubuwan da ke cikin BIOS a kan ƙwaƙwalwar filasha don haka ana iya sake rubuta shi ba tare da cire guntu daga katunan ba. Wannan yana ba da sauƙi, sabunta-mai amfani ta ƙarshe ga BIOS firmware don haka za a iya ƙara sabbin abubuwa ko za a iya yin kwari, amma kuma yana haifar da yiwuwar kwamfutar ta kamu da tushen root na BIOS. Bugu da ƙari, haɓaka BIOS wanda ya kasa na iya yin bulo ga katako.

Hadadden Extensible Firmware Interface (UEFI) magaji ne ga tsohuwar PC BIOS, da nufin magance gazawar fasaha. 

## Tarihi
A lokaci BIOS (Basic Input / Output System) an halitta ta Gary Kildall   da farko ya bayyana a cikin CP / M tsarin aiki a shekarar 1975,       yana bayanin takamaiman kayan aiki na CP / M wanda aka ɗora a lokacin lokacin taya wanda ke yin hulɗa kai tsaye tare da kayan aikin .  (Injin CP / M yawanci yana da mai ɗaukar boot kawai a cikin ROM ɗinsa. )

Sigogin na MS-DOS, PC DOS ko DR-DOS sun ƙunshi fayil da ake kira daban-daban " IO. SYS "," IBMBIO. COM "," IBMBIO. SYS ", ko" DRBIOS. SYS "; an san wannan fayil ɗin da" DOS BIOS "(wanda aka fi sani da" DOS I / O System ") kuma ya ƙunshi ƙananan takamaiman kayan aiki na tsarin aiki. Tare da keɓaɓɓen kayan aiki na musamman amma tsarin aiki mai zaman kansa "System BIOS", wanda ke zaune a cikin ROM, yana wakiltar analog ɗin zuwa " CP / M BIOS ".

BIOS asalin mallakar IBM PC ne wasu kamfanoni suka sake kera shi (kamar su Phoenix Technologies ) suna neman ƙirƙirar tsarin da zai dace. 

Tare da gabatar da injunan PS / 2, IBM ya rarraba System BIOS cikin ɓangarorin gaske da kuma kariya. Yankin yanayin-yanayi yana nufin samar da daidaituwa ta baya tare da tsarin aiki kamar DOS, sabili da haka aka sanya masa suna "CBIOS" (don "Compatibility BIOS"), yayin da "ABIOS" (don "Advanced BIOS") ya samar da sababbin hanyoyin musamman dace da yawa aiki tsarin kamar OS / 2 .

## Mai amfani da ke dubawa
BIOS na asalin IBM PC da XT ba su da wata hanyar amfani da mai amfani. An nuna lambobin kuskure ko saƙonni akan allon, ko kuma an kirkira jerin sauti don yin kuskuren sigina lokacin da ƙarfin gwajin kai tsaye (POST) bai ci gaba ba har zuwa nasarar ƙaddamar da adaftar nuni na bidiyo. Zaɓuɓɓuka akan IBM PC da XT an saita su ta hanyar sauyawa da masu tsalle a kan babban jirgi da kan katunan faɗaɗa . Farawa a tsakiyar shekarun 1990s, ya zama ruwan dare ga BIOS ROM don haɗawa da *"BIOS sanyi utility"* (BCU  ) ko "BIOS Setility utility", ana samun damarsa a tsarin ƙarfi ta wani maɓallin maɓalli. Wannan shirin ya bawa mai amfani damar saita zaɓuɓɓukan tsarin tsari, na nau'in da aka sanya ta ta amfani da maɓallin DIP, ta hanyar tsarin menu mai ma'amala wanda ake sarrafawa ta hanyar maballin. A cikin rikon kwarya lokacin, IBM-jituwa inji mai kwakwalwa — ciki har da IBM AT — gudanar saitunan sanyi a baturi-goyon baya RAM da kuma amfani da wani bootable sanyi shirin a floppy faifai, ba a ROM, to saita sanyi zabin kunshe ne a cikin wannan ƙwaƙwalwar ajiya. An kawata floppy disk din tare da kwamfutar, kuma idan ta bata tsarin saitunan ba za a iya canzawa ba. Haka aka yi amfani da shi gaba ɗaya ga kwamfutoci tare da motar EISA, wanda aka kira shirin daidaitawa mai amfani mai amfani na EISA (ECU).

Kwamfutar Wintel mai haɗa komputa yana ba da tsarin saiti na yau da kullun da babu canji a cikin yanayi daga abubuwan amfani na BIOS da ke zaune a ƙarshen shekarun 1990; mai amfani zai iya saita zaɓuɓɓukan kayan aiki ta amfani da faifan maɓalli da nuni na bidiyo. Injin Wintel na zamani na iya adana saitunan daidaitawa na BIOS a cikin flash ROM, wataƙila wannan flash ɗin ta ROM wacce ke riƙe da BIOS kanta.

## Aiki

### Fara tsarin
Masu sarrafa Intel na farko sun fara ne da adireshin jiki 000FFFF0h. Tsarin tare da masu sarrafawa daga baya suna ba da hankali don fara gudanar da BIOS daga tsarin ROM. 

If the system has just been powered up or the reset button was pressed ("cold boot"), the full power-on self-test (POST) is run. If Ctrl+Alt+Delete was pressed ("warm boot"), a special flag value stored in nonvolatile BIOS memory ("CMOS") tested by the BIOS allows bypass of the lengthy POST and memory detection.

POST yana ganowa, gwaje-gwaje da kuma ƙaddamar da na'urori irin su CPU, chipset, RAM, motherboard, katin bidiyo, keyboard, linzamin kwamfuta, rumbun diski, faifan diski na gani da sauran kayan aiki .

Fuskokin IBM na farko suna da tsari a cikin POST wanda zai zazzage wani shiri cikin RAM ta tashar keyboard da gudanar da shi.   An tsara wannan fasalin don gwajin masana'anta ko dalilan bincike.

### Taya tsari

Bayan an gama zaɓar ROM ɗin kuma duk samfuran ROM da aka gano tare da ingantattun bincike an kira su, ko kuma nan da nan bayan POST a cikin sigar BIOS wanda ba ya bincika zaɓi na ROM, BIOS ya kira INT 19h don fara aikin taya. Post-boot, shirye-shiryen da aka ɗora kuma suna iya kiran INT 19h don sake yin tsarin, amma dole ne su yi taka tsantsan don katse katsewa da sauran matakan kayan aikin kayan aiki waɗanda zasu iya tsoma baki tare da tsarin sake kunnawa na BIOS, ko kuma tsarin na iya rataye ko faɗuwa yayin da yake sakewa .

Lokacin da aka kira INT 19h, BIOS na ƙoƙari don gano software masu ɗora kaya a kan "na'urar ƙirar", kamar su Hard disk, floppy disk, CD, ko DVD . Yana loda kuma yana aiwatar da software na farko da ya samo, yana bashi iko da PC. 

BIOS yana amfani da na'urorin taya da aka saita a cikin ƙwaƙwalwar BIOS mai ban tsoro ( CMOS ), ko, a cikin PC na farko, sauya DIP A BIOS jami'in dake duba yawan kowane na'urar domin ganin idan shi ne bootable da yunƙurin load da farko kansu ( taya kansu ). Idan ba za a iya karanta fannin ba, BIOS zai ci gaba zuwa na gaba. Idan aka karanta fannin cikin nasara, wasu BIOS za su kuma bincika sa hannun bangaren taya 0x55 0xAA a baiti biyun karshe na bangaren (wanda ya fi tsawon 512 bytes), kafin su yarda da bangaren taya da kuma la’akari da na’urar da za a iya amfani da ita. 

Lokacin da aka samo na'urar da za a iya amfani da ita, BIOS tana canja wurin sarrafawa zuwa ɓangaren da aka ɗora. BIOS ba ta fassara abubuwan da ke cikin takalmin sata ban da yiwuwar bincika sa hannun sashin taya a cikin bytes biyu da suka gabata. Fassarar tsarin data kamar teburin bangare da kuma BIOS Parameter Blocks ana yin ta ne ta hanyar shirin taya a bangaren taya ko kuma ta wasu shirye-shiryen da aka loda ta hanyar aikin taya.

Na'urar da ba diski ba kamar adaftan cibiyar sadarwa tana yunƙurin ɗorawa ta hanyar hanyar da za a bayyana ta zaɓin ta na ROM ko makamancin abin da aka haɗa a cikin mahaɗin BIOS ROM. Kamar wannan, zaɓi ROMs na iya yin tasiri ko maye gurbin tsarin taya wanda aka bayyana ta motherboard BIOS ROM.

Tare da daidaitaccen takalmin talla na kafafen yada labarai na El Torito, togararren faifan a zahiri yana kwaikwayon kamfani mai nauyin 3.5 "mai nauyin gaske zuwa BIOS don manufar taya. Karanta "bangaren farko" na CD-ROM ko DVD-ROM bawai wani aiki bane wanda aka bayyana shi kamar yadda yake a kan floppy disk ko kan diski. Bugu da ƙari, mawuyacin yanayin matsakaici ya sa ya zama da wahala a rubuta shirin taya mai amfani a cikin ɓangare ɗaya. Kayan kwalliyar kwalliyar kwalliya na iya ɗauke da software wanda ke ba da damar zuwa matsakaiciyar hanyar gani a tsarinta na asali.

#### Boot fifiko
Mai amfani zai iya zaɓar fifikon taya wanda BIOS ya aiwatar. Misali, galibin kwamfutoci suna da rumbun diski wanda za a iya sawa, amma wani lokacin ana samun madogara mai matsakaicin motsi wacce take da fifikon fifikon taya, saboda haka mai amfani na iya sa a cire diski mai cirewa.

A mafi yawan BIOSes na zamani, mai amfani zai iya saita oda mafi fifiko ta boot. A cikin tsofaffin BIOSes, zaɓuɓɓukan fifikon ƙarancin taku zaɓaɓɓu ne; a cikin BIOS na farko, an aiwatar da wani tsayayyen tsari wanda aka tsara shi, tare da fararen diski na farko, tsayayyen diski (watau mawuyacin diski) na biyu, kuma galibi babu wasu na'urorin taya masu goyan baya, dangane da sauye-sauyen waɗannan ƙa'idodin ta hanyar zaɓin ROM da aka girka. BIOS a cikin PC na farko shima galibi zai iya farawa ne kawai daga farkon disk ɗin diski na farko ko na farkon mashigar diski, koda kuwa an girke mashin biyu.

#### Rashin nasarar taya
A kan asalin IBM PC da XT, idan ba a sami faifan bootable ba, an fara ROM BASIC ta hanyar kiran INT 18h. Tunda programsan shirye-shirye sunyi amfani da BASIC a cikin ROM, masu yin PC ɗin clone sun bar shi; to, kwamfutar da ta kasa farawa daga faifai za ta nuna "Babu ROM BASIC" kuma ta dakatar (a cikin martani ga INT 18h).

Daga baya kwamfutoci zasu nuna sako kamar "Babu wani bootable disk da aka samo"; wasu za su nemi a saka faifai sannan a danna mabudi don sake gwada aikin taya. BIOS ta zamani na iya nuna komai ko kuma ta atomatik ta iya shigar da mai amfani ta BIOS lokacin da aikin taya ya kasa.

### Yanayin taya
Yanayi don shirin taya yana da sauqi: CPU yana cikin yanayi na gaske kuma ba a fayyace mahimman manufa da rajistar yanki, sai dai SS, SP, CS, da DL. CS: IP koyaushe yana nuna adireshin jiki `0x07C00` . Abin da ke darajar CS da IP a zahiri basu da ma'ana sosai. Wasu BIOS suna amfani da CS: IP na `0x0000:0x7C00` yayin da wasu na iya amfani da `0x07C0:0x0000` . Saboda ana ɗora shirye-shiryen taya a koyaushe a wannan tsayayyen adireshin, babu buƙatar shirin kora da za a iya sakewa. DL na iya ƙunsar lambar tuki, kamar yadda aka yi amfani da INT 13h, na na'urar taya. SS: SP yana nuna madaidaicin tari wanda mai yuwuwa babba ne don tallafawa katsewar kayan aiki, amma in ba haka ba SS da SP ba a bayyana su ba. (Dole ne a riga an saita tsayi domin yin katsewa don ayi aiki, kuma dole ne a kunna katsewa domin katsewar tsarin lokaci, wanda BIOS koyaushe ke amfani da aƙalla don kula da ƙididdigar lokaci da kuma abin da yake farawa yayin POST, don yin aiki kuma don maɓallin kewaya suyi aiki. Maballin yana aiki koda ba a kira sabis ɗin keyboard na BIOS ba; Ana karɓar maɓallan maɓalli kuma an sanya su a cikin nau'ikan nau'in nau'in nau'in nau'in-nau'in 15 wanda BIOS ke kiyayewa. ) Dole ne shirin taya ya sanya tsintsiya madaurinki daya, saboda ba a san girman adadin da BIOS ya kafa ba kuma wurin da yake yana canzawa; kodayake shirin taya na iya bincikar tsoho ta hanyar nazarin SS: SP, ya fi sauƙi kuma ya fi guntu don kawai kafa ƙa'idodi ba tare da ƙa'idodi ba.

A lokacin taya, ana samun dukkan sabis na BIOS, kuma ƙwaƙwalwar da ke ƙasa adireshin `0x00400` ƙunshe da teburin katsewa na katsewa . BIOS POST ta ƙaddamar da ƙayyadaddun tsarin lokaci, dakatar da masu sarrafawa, DMA mai kulawa (s), da sauran kayan aikin katako / kwakwalwan kwamfuta kamar yadda ya kamata don kawo duk sabis ɗin BIOS zuwa matsayi a shirye. DRAM na wartsakewa ga dukkan tsarin DRAM a cikin mahimmin ƙwaƙwalwa da ƙara ƙwaƙwalwar ajiya, amma ba lallai ba ne faɗaɗa ƙwaƙwalwar ajiya, an saita ta kuma tana gudana. A katse vectors m ga BIOS interrupts an saita zuwa batu a dace shigarwa maki a cikin BIOS, hardware katse vectors ga na'urorin initialized da BIOS sun kasance sa zuwa nufi da BIOS-bayar ISRs, da kuma wasu sauran interrupts, ciki har da wadanda wanda BIOS ke samarwa don shirye-shirye don yin ƙugiya, an saita su zuwa mummunan ISR wanda ya dawo nan da nan. BIOS tana riƙe da wani toshe na tsarin RAM a adiresoshin `0x00400–0x004FF` tare da wasu sigogi da aka fara yayin POST. Duk ƙwaƙwalwar ajiya a sama da adireshin `0x00500` iya amfani da shirin taya; yana ma iya sake rubuta kansa.

## Fadada (zaɓi ROMS)
Katunan gefe kamar rumbun diski na rudani mai karɓar adaftan bas da katunan bidiyo suna da nasu zaɓi na faɗaɗawa na BIOS, wanda ke ba da ƙarin ayyuka ga BIOS. Code a cikin waɗannan haɓaka yana gudana kafin BIOS ta fara aiki da tsarin aiki daga adana taro . Waɗannan ROMs yawanci suna gwadawa da fara kayan aiki, ƙara sabbin sabis na BIOS, ko maye gurbin sabis na BIOS da suke tare da ayyukansu. Misali, mai kula da SCSI galibi yana da haɓakar BIOS na ROM wanda ke ƙara tallafi don rumbun kwamfutocin da aka haɗa ta wannan mai sarrafawa. Extensionarin ROM zai iya ɗauka bisa tsarin aiki, ko kuma zai iya aiwatar da tsarin taya daban gaba ɗaya kamar haɓaka cibiyar sadarwa . Yin aiki da tsarin komputa mai jituwa da IBM ana iya canza shi gaba ɗaya ta cire ko saka katin adaftan (ko guntu na ROM) wanda ya ƙunshi ƙara girman BIOS.

BIOS ɗin motherboard yawanci yana ƙunshe da lambar don samun damar haɗin kayan aikin kayan aikin da ake buƙata don haɗin haɗin bootstrapping wanda aka haɗa tare da haɗin ajiya. Kari akan haka, katunan adaftan da aka saka kamar su SCSI, RAID, katunan hanyar sadarwa, da katunan bidiyo galibi sun haɗa da nasu BIOS (misali Bidiyo BIOS ), haɓaka ko maye gurbin lambar BIOS na tsarin don ɓangaren da aka bayar. Hatta na'urorin da aka gina a cikin mahadi na iya nuna hali ta wannan hanyar; zaɓi na ROMs na iya zama wani ɓangare na motherboard BIOS.

Katin ƙara-yana buƙatar zaɓi na ROM idan katin na ba ta da goyan bayan BIOS na uwa kuma katin yana buƙatar farawa ko samun dama ta hanyar sabis na BIOS kafin a ɗora tsarin aiki (yawanci wannan yana nufin ana buƙata a cikin tsarin taya ). Koda lokacin da ba'a buƙata ba, zaɓi na ROM zai iya ba da damar amfani da katin adaftan ba tare da loda kayan aikin direba ba daga na'urar ajiya bayan fara farawatare da wani zaɓi na ROM, ba a ɗaukar lokaci don ɗora wa direba, direba ba ya ɗaukar sarari a cikin RAM ko a kan faifai, kuma software na direba a kan ROM koyaushe yana tare da na'urar don haka ba za a iya raba su biyu ba da gangan ba. Hakanan, idan ROM ɗin tana kan katin, duka kayan aikin haɗi da software na direba da ROM ke bayarwa an haɗa su tare ba tare da ƙarin ƙoƙari don girka software ba. Advantagearin fa'idar ROM akan wasu farkon tsarin PC (musamman haɗe da IBM PCjr) shine cewa ROM tayi sauri fiye da babban tsarin RAM. (A kan tsarin zamani, lamarin ya kasance baya ga wannan, kuma lambar BIOS ROM galibi ana kwafa ("inuwa") cikin RAM saboda haka zai yi aiki da sauri. )

Akwai hanyoyi da kayan amfani da yawa don bincika abubuwan da ke cikin BIOS na katako da fadada ROMs, kamar Microsoft DEBUG ko Unix dd .

### Boot hanya
Idan fadada ROM yana son canza yadda tsarin takalmi yake (kamar daga na'urar network ko adaftan SCSI) ta hanyar hadin gwiwa, zata iya amfani da *BIOS Boot Specification* (BBS) API don yin rijistar ikon yin hakan. Da zarar fadada ROMs sun yi rijista ta amfani da API na BBS, mai amfani zai iya zaɓar cikin wadatar zaɓuɓɓukan taya daga cikin ƙirar mai amfani da BIOS. Wannan shine dalilin da ya sa yawancin aiwatar da BBS PC BIOS ba za su ƙyale mai amfani ya shiga aikin amfani da BIOS ba har sai faɗaɗa ROMs sun gama aiwatarwa da yin rajistar kansu tare da BBS API.

Hakanan, idan fadada ROM yana son canza yadda tsarin takalmi yake ba tare ba, zai iya sanya INT 19h ko wasu tsangwama da aka saba kira wanda ya katse 19h, kamar INT 13h, sabis ɗin diski na BIOS, don katse aikin taya na BIOS. Sannan zai iya maye gurbin aikin boot na BIOS da ɗayan nasa, ko kuma kawai zai iya canza jerin kayan aikin ta hanyar shigar da ayyukanta na taya a ciki, ta hana BIOS gano wasu na'urori azaman bootable, ko duka biyun. Kafin a ƙaddamar da Bayanin Takalma na BIOS, wannan ita ce kawai hanya don faɗakar da ROM don aiwatar da damar taya ga na'urori da ba a tallafawa don farawa ta asalin BIOS na mahaifa.

### Farawa
ayan motherboard BIOS ya gama POST din sa, mafi yawan nau'ikan BIOS suna binciken wasu samfuran ROM, wadanda kuma ake kira BIOS extension ROMs, kuma suke aiwatar dasu. BIOS ɗin motherboard na sikanin ƙarin ROMs a cikin wani ɓangare na " yankin ƙwaƙwalwar na sama " (ɓangaren filin adireshin zahiri na x86 a adireshin 0xA0000 na sama da sama) kuma yana gudanar da kowace ROM ɗin da aka samo, cikin tsari. Don gano zaɓi na ISA zaɓi na ROM ɗin ƙwaƙwalwar ajiya, aiwatar da BIOS yana bincika sararin adireshin ainihin yanayin daga `0x0C0000` zuwa `0x0F0000` akan 2&nbsp;KiB *iyaka, neman sa hannun* ROM mai lamba biyu: 0x55 mai biye da 0xAA. A cikin ingantaccen faɗaɗa ROM, wannan sa hannun yana biye da baiti ɗaya mai nuna adadin 512-byte toshe faɗakarwar da Roman yake zaune a cikin ainihin ƙwaƙwalwar ajiya, kuma baiti na gaba shine zaɓin shigar da ROM ɗin (wanda aka fi sani da "shigar da biya") . Calculatedididdigar yawan adadin da aka ƙayyade na ƙididdigar 512-byte ana lasafta shi, kuma idan ROM ɗin tana da rajista mai inganci, BIOS yana canja wurin iko zuwa adireshin shigarwa, wanda a cikin ƙarawar BIOS na yau da kullun ya kamata ya zama farkon tsarin farawa na yau da kullun.

A wannan gaba, lambar ƙara ROM ɗin ta karɓa, yawanci gwaji da ƙaddamar da kayan aikin da yake sarrafawa da yin rijistar vectors masu katsewa don amfani da aikace-aikacen bayan taya. Yana iya amfani da sabis na BIOS (gami da waɗanda aka bayar da su ta hanyar zaɓin farko na ROM) don ba da damar daidaitawar mai amfani, don nuna bayanan bincike, ko yin wani abu da yake buƙata. Zai yiwu cewa zaɓi na ROM ba zai dawo ba ga BIOS, yana ƙaddamar da jerin takalmin BIOS gaba ɗaya.

Wani zaɓi na ROM yakamata ya koma BIOS bayan kammala aikin farawa. Da zarar (kuma idan) zaɓi na ROM ya dawo, BIOS yana ci gaba da neman ƙarin zaɓin ROMs, yana kiran kowannensu kamar yadda aka same shi, har sai an zaɓi dukkan yankin ROM ɗin da ke cikin sararin ƙwaƙwalwar.

### Sanya jiki

Zaɓin ROMs yakan zauna akan katunan adafta. Koyaya, PC na asali, kuma wataƙila PC XT, suna da maɓallin soket na ROM akan katako ("allon tsarin" a cikin sharuɗɗan IBM) wanda za'a iya shigar da wani zaɓi na ROM, kuma ROMS guda huɗu waɗanda ke ƙunshe da mai fassara BASIC zasu iya. Hakanan za'a cire shi kuma a maye gurbin sa da ROMs na al'ada wanda zai iya zama zaɓi ROMs. IBM PCjr na musamman ne tsakanin PCs wajen samun ramukoki guda biyu na ROM a gaba. Gundura a cikin waɗannan ramuka suna taswira zuwa yanki ɗaya na yankin ƙwaƙwalwar na sama da aka yi amfani da shi don zaɓin ROMs, kuma harsasan na iya ƙunsar zaɓuɓɓukan zaɓi na ROM waɗanda BIOS za ta gane. Hakanan ginshiƙan na iya ƙunsar wasu nau'ikan kayan haɗin ROM, kamar su BASIC shirye-shirye, waɗanda ake sarrafa su daban. Daya PCjr harsashi na iya ƙunsar da dama ROM kayayyaki daban-daban, yiwu adana tare a daya ROM guntu.

## Ayyukan tsarin aiki
BIOS ROM an keɓance shi zuwa kayan aikin masana'anta na musamman, yana ba da sabis na ƙananan matakai (kamar karanta maɓallin keystroke ko rubuta wani sashin bayanai zuwa diskette) don samar da su ta daidaitacciyar hanyar zuwa shirye-shirye, gami da tsarin aiki. Misali, IBM PC na iya samun ko dai monochrome ko adaftan nuni na launi (ta amfani da adreshin ƙwaƙwalwar ajiya da kayan aiki daban-daban), amma guda ɗaya, daidaitacce, ana kiran kiran tsarin BIOS don nuna hali a takamaiman matsayi akan allo a yanayin rubutu ko yanayin zane .

BIOS tana ba da ƙaramin laburare na ayyukan shigarwa / fitarwa na asali don aiki da kewayen gefe (kamar su keyboard, rubutu mara kyau da ayyukan nuni da sauransu). Lokacin amfani da MS-DOS, ana iya samun damar sabis na BIOS ta hanyar aikace-aikacen aikace-aikacen (ko ta MS-DOS) ta hanyar aiwatar da umarnin INT 13h wanda ya katse umarni don samun damar ayyukan faifai, ko ta hanyar aiwatar da ɗayan wasu takamaiman bayanan BIOS da aka katse kira don samun damar bidiyo nuni, madanni, kaset, da sauran ayyukan na'urar.

Tsarukan aiki da software masu zartarwa wadanda aka tsara don maye gurbin wannan aikin firmware na asali suna samar da musanya kayan masarufi ga kayan aikin software. Aikace-aikace na iya samar da waɗannan ayyukan ga kansu. Wannan ya fara ko da a cikin shekarun 1980 a ƙarƙashin MS-DOS, lokacin da masu shirye-shirye suka lura cewa amfani da sabis ɗin bidiyo na BIOS don nuna zane yana da jinkiri sosai. Don haɓaka saurin fitowar allo, shirye-shirye da yawa sun kewaye BIOS kuma an tsara kayan aikin nunin bidiyo kai tsaye. Sauran masu shirye-shiryen zane-zane, musamman ba kawai a cikin demoscene ba, sun lura cewa akwai iyawar fasaha na adaftan nuni na PC waɗanda IBM BIOS ba su da tallafi kuma ba za a iya cin gajiyar su ba tare da kewaye ta ba. Tunda BIOS mai jituwa ta BIOS tayi aiki a cikin ainihin yanayin Intel, tsarin aiki waɗanda ke gudana cikin yanayin kariya akan 286 kuma masu sarrafawa daga baya sun buƙaci direbobin na'urar kayan aiki masu dacewa tare da yanayin yanayin kariya don maye gurbin sabis na BIOS.

A cikin PCs na zamani da ke aiki da tsarin aiki na zamani (kamar su Windows da Linux ) ana amfani da BIOS na katse kira ne kawai a lokacin da ake farawa da shigar da tsarin aiki na farko. Kafin nunin allon zane na farko na tsarin aiki, ana sarrafa abubuwan shigarwa da fitarwa ta hanyar BIOS. Kayan menu kamar menu na rubutu na Windows, wanda ke bawa masu amfani damar zaɓar tsarin aiki don taya, don shiga cikin yanayin aminci, ko don amfani da kyakkyawan sanannen ƙarshe, an nuna shi ta hanyar BIOS kuma yana karɓar shigarwar keyboard ta hanyar BIOS. 

Kwamfutocin zamani da yawa na zamani har yanzu suna iya yin buda da gudanar da tsoffin tsarin aiki kamar su MS-DOS ko DR-DOS waɗanda suka dogara da BIOS sosai don kayan wasan su da I / O na diski, suna ba da cewa tsarin yana da BIOS, ko kuma CSM mai iya yuwuwar UEFI.

### Mai sabunta microcode
Masu sarrafa Intel suna da microcode mai sake sabuntawa tun lokacin da micro microitektition na P6.   Masu sarrafa AMD suna da microcode mai sabuntawa tun lokacin da K7 microarchitecture. BIOS yana dauke da faci zuwa microcode mai sarrafawa wanda ke gyara kurakurai a cikin microcode na farkon mai sarrafawa; microcode an loda shi a cikin SRAM na mai sarrafawa saboda haka sake tsara shirye-shirye ba ya dagewa, saboda haka ana yin ɗora kwatancen sabunta microcode a duk lokacin da tsarin yayi ƙarfi. Ba tare da lambar microcode da za a iya sabuntawa ba, za a buƙaci musanya mai sarrafawa mai tsada;  alal misali, kwaron Pentium FDIV ya zama fiasco mai tsada ga Intel saboda yana buƙatar samin samfurin saboda asalin micro processor mai aiki na Pentium ba za a iya sake tsara shi ba. Tsarin aiki zai iya sabunta babban microcode mai sarrafawa kuma.  

Wasu BIOS suna ɗauke da teburin bayanin lasisin lasisin software (SLIC), sa hannu na dijital wanda aka ƙera a cikin BIOS ta asalin masana'antun kayan aiki (OEM), misali Dell . An saka SLIC a cikin teburin bayanan ACPI kuma babu lambar aiki.  

Kamfanonin komputa da ke rarraba nau'ikan OEM na Microsoft Windows da software na aikace-aikacen Microsoft na iya amfani da SLIC don tabbatar da lasisi ga OEM Windows Installation disk da system recovery disk mai ɗauke da software na Windows. Tsarin tsari tare da SLIC ana iya yin aiki tare da maɓallin samfurin OEM, kuma suna tabbatar da takardar shaidar OEM da aka tsara ta XML akan SLIC a cikin BIOS azaman hanyar kunna kai (duba Tsarin Kullewa na Tsarin, SLP). Idan mai amfani yayi sabon shigar na Windows, zasu buƙaci mallakin duka maɓallin OEM (ko dai SLP ko COA) da takaddar dijital don SLIC ɗinsu don kewaye kunnawa.  Ana iya cimma wannan idan mai amfani yayi aikin dawo da shi ta amfani da wani hoto da aka riga aka tsara wanda aka bayar ta OEM. Masu amfani da wuta zasu iya kwafin fayilolin takaddar takaddama daga hoton OEM, su yanke maɓallin samfurin SLP, sannan suyi SLP kunnawa da hannu. Fashewa don rarar abubuwan Windows da ba gaskiya ba galibi suna gyara SLIC ko yin koyi da shi don ƙetare kunna Windows.

Wasu aiwatarwar BIOS suna ba da izinin overclocking, aikin da aka daidaita CPU zuwa ƙimar agogo mafi girma fiye da ƙirar mai ƙira don ƙarfin tabbaci. Overclocking na iya, duk da haka, ya daidaita tsarin amintacce cikin ƙarancin kwakwalwa mai kwakwalwa kuma gabaɗaya ya rage tsawon rayuwar. Cloara kwalliya, lokacin da aka aiwatar da shi ba daidai ba, na iya haifar da haɗuwa da zafi sosai da sauri har su lalata kansu ta hanyar inji. 

### Amfani da zamani
Wasu tsoffin tsarin aiki, misali MS-DOS, sun dogara da BIOS don aiwatar da mafi yawan ayyukan shigarwa / fitarwa a cikin PC. 

Kira ainihin yanayin sabis na BIOS kai tsaye ba shi da tasiri don yanayin kariya (da dogon yanayin ) tsarin aiki. Ba a amfani da kira na katsewa ta BIOS ta tsarin aiki da yawa na zamani bayan sun fara lodawa.

A cikin shekarun 1990s, BIOS sun samar da wasu hanyoyin kariya don Microsoft Windows, Linux da BSD tsarin aiki, kamar Advanced Power Management (APM), Legacy Plug da Play (Legacy PnP), Desktop Management Interface (DMI), PCI BIOS,   VESA BIOS Fadada (VBE) da Bayanin MultiProcessor (MPS). Farawa daga 2000s, yawancin BIOS suna ba da ACPI, SMBIOS da musayar hanyoyin VBE don tsarin aiki na zamani.     Tsarukan aiki na zamani suna loda taswirar ƙwaƙwalwar e820 a farawa. 

Bayan tsarin aiki sun loda, lambar Yanayin Gudanar da Tsarin Tsarin yana aiki a cikin SMRAM. Tun daga 2010, fasahar BIOS tana cikin tsaka-tsakin tsari zuwa UEFI . 

## Kanfigareshan

### Saitin mai amfani
A tarihi, BIOS a cikin IBM PC da XT ba su da haɗin ginin mai amfani. Sigogin BIOS a cikin PCs na baya (XT-class) ba za'a iya daidaita software ba; maimakon haka, masu amfani suna saita zaɓuɓɓuka ta hanyar sauya DIP a kan katako. Kwamfutoci daga baya, gami da duk nau'ikan komputa na IBM tare da 80286 CPUs, suna da ƙwaƙwalwar BIOS mara ƙamshi mai ƙarfi (CMOS RAM chip) mai riƙe saitunan BIOS.  Wadannan saitunan, kamar nau'in adaftan bidiyo, girman ƙwaƙwalwar ajiya, da sifofin faya-faya, za a iya saita su ta hanyar gudanar da tsarin daidaitawa daga diski, ba a gina shi cikin ROM ba. An saka "diskette mai bayani" na musamman a cikin IBM AT don daidaita saituna kamar girman ƙwaƙwalwar ajiya.

jSigogin BIOS na farko basu da kalmomin shiga ko zaɓuɓɓukan zaɓi na kayan taya. BIOS ta kasance mai lamba mai kyan gani don taya daga farkon floppy drive, ko, idan hakan ya faskara, disk na farko. Ikon samun damar shiga cikin farkon ajin injunan AT ta hanyar sauya makullin jiki ne (wanda ba shi da wahalar kayarwa idan za'a iya buɗe batun kwamfutar). Duk wanda zai iya kunna kwamfutar zai iya kora ta.

Daga baya, kwamfyutoci masu aji 386 sun fara haɗa haɗin mai amfani na BIOS a cikin ROM ɗin kanta, tare da lambar BIOS; wadannan kwamfutocin galibi suna shiga cikin kayan saitin BIOS idan an danne wani mabudi ko mabuɗin maɓalli, in ba haka ba ana aiwatar da BIOS POST da tsarin taya.

Aikace -aikacen saitin BIOS na zamani yana da keɓaɓɓen mai amfani da rubutu (TUI) ko mai amfani da hoto (GUI) wanda ake samun dama ta latsa wani maɓalli akan maballin lokacin da PC ta fara. Yawancin lokaci, ana tallata maɓallin don ɗan gajeren lokaci yayin farkon farawa, misali "Danna DEL don shigar da Saiti". Maɓallin na ainihi ya dogara da takamaiman kayan aiki. Abubuwan da ke cikin kayan aikin saitin BIOS yawanci sun haɗa da:

* Harhadawa, kunnawa da kashe abubuwan kayan aikin
* Kafa lokacin tsarin
* Kafa tsari na taya
* Kafa kalmomin shiga daban -daban, kamar kalmar sirri don tabbatar da samun dama ga masarrafar mai amfani da BIOS da hana masu amfani da muguntar tayar da tsarin daga na’urorin ajiya na šaukuwa mara izini, ko kalmar wucewa don bugun tsarin.

### Kula da kayan aiki
Allon saitin BIOS na zamani yana fasalta **Matsayin Kiwon Lafiya na PC** ko **shafin Kula da Kayan aiki**, wanda ke hulɗa kai tsaye tare da guntun Kula da Hardware na babban allo.  Wannan yana ba da damar saka idanu CPU da zazzabi chassis , ƙarfin wutar lantarki da ƙungiyar samar da wutar lantarki ke bayarwa, gami da saka idanu da sarrafa saurin magoya bayan da aka haɗa da uwa.

Da zarar an ɗora tsarin, saka idanu na kayan masarufi da sarrafa fan na kwamfuta yawanci ana yin ta kai tsaye ta guntun Hardware Monitor kanta, wanda zai iya zama guntu daban, wanda aka haɗa ta I²C ko SMBus, ko ya zo a matsayin wani ɓangare na Super I/O bayani, interfaced Ta hanyar Ƙididdigar Ƙananan Pin (LPC).  Wasu tsarin aiki, kamar NetBSD tare da envsys da OpenBSD tare da sysctl hw.sensors, fasali mai haɗawa tare da masu saka idanu na kayan aiki.

Koyaya, a wasu yanayi, BIOS kuma yana ba da mahimman bayanai game da saka idanu na kayan aiki ta hanyar ACPI, a cikin haka, tsarin aiki na iya amfani da ACPI don yin sa ido kan kayan aiki.  

### Sake tsarawa

A cikin kwamfutocin zamani ana adana BIOS a cikin EEPROM ko ƙwaƙwalwar filashin NOR da za a iya sake rubutawa, yana ba da damar maye gurbin abubuwan da ke ciki. Wannan sake rubuta abun ciki wani lokaci ana kiransa *walƙiya* . Ana iya yin ta ta wani shiri na musamman, wanda yawanci ke samar da tsarin, ko a POST, tare da hoton BIOS a cikin rumbun kwamfutarka ko kebul na USB. Wani lokaci ana kiran fayil ɗin da ke ɗauke da irin waɗannan abubuwan "hoton BIOS". Ana iya sabunta BIOS don haɓakawa zuwa sabon salo don gyara kwari ko samar da ingantaccen aiki ko don tallafawa sabbin kayan aikin.

## Hardware

An adana asalin IBM PC BIOS (da kaset BASIC) akan kwakwalwar da aka tsara ta ƙwaƙwalwar ajiya kawai (ROM) a cikin soket akan motherboard. Masu amfani za su iya maye gurbin ROMs, amma ba a canza su ba. Don ba da damar sabuntawa, kwamfutoci masu jituwa da yawa sun yi amfani da na’urorin ƙwaƙwalwar BIOS da za a iya sake tsara su kamar na EPROM, EEPROM da na’urar ƙwaƙwalwar ƙwaƙwalwa (galibi NOR flash ). A cewar Robert Braver, shugaban na BIOS manufacturer Micro Firmware, **Flash BIOS** kwakwalwan kwamfuta ya zama na kowa a kusa da 1995 saboda electrically erasable rawa (EEPROM) kwakwalwan kwamfuta ne mai rahusa da kuma sauki a shirin fiye da misali ultraviolet erasable rawa ( EPROM ) kwakwalwan kwamfuta. An tsara shirye-shiryen kwakwalwan kwamfuta (kuma an sake tsara su) a cikin kewaye, yayin da ake buƙatar cire kwakwalwan EPROM daga uwa-uba don sake shirye-shirye.  Ana haɓaka sigogin BIOS don amfani da sabbin sigogin kayan aiki da gyara kwari a cikin bita na baya na BIOS. 

Da farko tare da IBM AT, Kwamfutoci sun goyi bayan agogon kayan aiki wanda aka saita ta BIOS. Yana da ɗan ƙarni wanda ya ba da izinin canza ƙarni da hannu lokacin da shekarar 2000 ta faru. Yawancin bita na BIOS da aka kirkira a 1995 kuma kusan duk sake fasalin BIOS a 1997 sun goyi bayan shekara ta 2000 ta hanyar saita bitar ƙarni ta atomatik lokacin da agogo ya birkice tsakar dare, 31 ga Disamba 1999. 

An haɗa kwakwalwan filasha na farko a cikin motar ISA . Farawa a cikin 1998, filashin BIOS ya koma motar LPC, mai maye gurbin aikin ISA, biyo bayan sabon daidaitaccen aiwatarwa da aka sani da "cibiyar firmware" (FWH). A cikin 2006, ƙwaƙwalwar filasha ta BIOS ta koma cikin motar SPI. 

Girman BIOS, da ƙarfin ROM, EEPROM, ko wasu kafofin watsa labarai da za a iya adana su, ya ƙaru a kan lokaci yayin da aka ƙara sabbin fasali a cikin lambar; Sigogin BIOS yanzu suna da girma har zuwa megabytes 32. Don bambanta, asalin IBM PC BIOS yana cikin 8&nbsp;KB mask ROM. Wasu motherboards na zamani sun haɗa har ma da manyan fayilolin NAND flash memory ICs a cikin jirgi waɗanda ke da ikon adana cikakken tsarin aiki, kamar wasu rarraba Linux . Misali, wasu litattafan rubutu na ASUS sun haɗa da Splashtop OS wanda aka saka cikin ICs ɗin ƙwaƙwalwar ajiyar filasha ta NAND.  Koyaya, ra'ayin haɗa tsarin aiki tare da BIOS a cikin ROM na PC ba sabo bane; a cikin 1980s, Microsoft ya ba da zaɓi na ROM don MS-DOS, kuma an haɗa shi a cikin ROMs na wasu clones na PC kamar Tandy 1000 HX .

An sami wani nau'in guntu na firmware akan IBM PC AT da farkon masu jituwa. A cikin AT, microcontroller ke sarrafa kebul ɗin kebul ɗin tare da ƙwaƙwalwar ƙwaƙwalwa mai shirye -shirye. A kan IBM AT, wannan na’ura ce mai rahusa 40, yayin da wasu masana'antun ke amfani da sigar EPROM na wannan guntu wanda yayi kama da EPROM. An kuma sanya wannan mai kula da aikin ƙofar A20 don sarrafa ƙwaƙwalwa sama da iyakar megabyte ɗaya; lokaci -lokaci haɓaka wannan “keyboard BIOS” ya zama dole don cin gajiyar software da za ta iya amfani da babban ƙwaƙwalwa.

BIOS na iya ƙunsar abubuwa kamar Memory Reference Code (MRC), wanda ke da alhakin fara ƙwaƙwalwar (misali. SPD da farkon lokacin ƙwaƙwalwar ajiya).   

BIOS na zamani ya haɗa da Injin Gudanar da Intel  ko AMD Platform Security Processor firmware.

## Masu sayarwa da samfurori

IBM ya buga dukkan jerin BIOS ɗin don PC ɗinsa na asali, PC XT, PC AT, da sauran samfuran PC na zamani, a cikin kari na *Littafin Jagorar Fasaha* na IBM PC ga kowane nau'in injin. Sakamakon buga jerin BIOS shine cewa kowa zai iya ganin ainihin abin da ainihin BIOS ke yi da yadda yake yi.

A watan Mayu 1984 Kamfanin Phoenix Software Associates ya fito da ROM-BIOS na farko, wanda ya ba OEM damar gina clone masu jituwa sosai ba tare da sun canza injin IBM PC BIOS da kansu ba, kamar yadda Compaq ya yi wa Fir ɗin, yana taimakawa haɓaka ci gaba a cikin PC- masana'antu masu jituwa da siyar da sigogin DOS ba na IBM ba.  Kuma farkon Megatrends na Amurka (AMI) BIOS an sake shi a 1986.

Sabbin ƙa'idodin da aka ɗora akan BIOS galibi ba tare da cikakkun takaddun jama'a ko kowane jerin BIOS ba. Sakamakon haka, ba abu ne mai sauƙi ba don koyan cikakkun bayanai game da ƙarin abubuwan da ba na IBM ba ga BIOS kamar game da manyan ayyukan BIOS.

Yawancin masu samar da motherboard na PC suna ba da lasisin BIOS "core" da kayan aiki daga wani ɓangare na kasuwanci, wanda aka sani da "dillalin BIOS mai zaman kansa" ko IBV. Sannan mai kera uwa -uba ya keɓanta wannan BIOS don dacewa da kayan aikin sa. A saboda wannan dalili, sabbin BIOSes ana samun su kai tsaye daga masana'anta na uwa. Manyan dillalan BIOS sun haɗa da Megatrends na Amurka (AMI), Insyde Software, Phoenix Technologies da Byosoft. Tsoffin dillalai sun haɗa da Software Award da Microid Research wanda Phoenix Technologies suka samu a 1998; Daga baya Phoenix ya cire sunan alamar lambar yabo. Janar Software, wanda kuma Phoenix ya samo shi a 2007, ya sayar da BIOS don tsarin da aka saka bisa tsarin Intel.

Al'umman bude-tushen sun haɓaka ƙoƙarin su don haɓaka maye gurbin BIOSes masu mallakar da abubuwan da za su kasance a nan gaba tare da takwaransa mai buɗe ido ta hanyar libreboot, coreboot da ayyukan OpenBIOS / Open Firmware . AMD ta ba da ƙayyadaddun samfur don wasu kwakwalwan kwamfuta, kuma Google tana ɗaukar nauyin aikin. Tyan mai samar da katako na Tyan yana ba da coreboot kusa da daidaitaccen BIOS tare da layin Opteron na uwa -uba.

## Tsaro

EEPROM da kwakwalwar ƙwaƙwalwar Flash suna da fa'ida saboda mai amfani zai iya sabunta su cikin sauƙi; al'ada ce ga masana'antun kayan aikin don fitar da sabuntawar BIOS don haɓaka samfuran su, haɓaka jituwa da cire kwari . Koyaya, wannan fa'idar tana da haɗarin cewa sabunta BIOS da aka yi ba daidai ba ko gurɓatawa na iya sa kwamfutar ko na'urar ta zama mara amfani. Don guje wa waɗannan yanayi, BIOSes na baya -bayan nan suna amfani da “toshe bututu”; wani ɓangare na BIOS wanda ke fara aiki kuma dole ne a sabunta shi daban. Wannan lambar tana tabbatarwa idan sauran BIOS ba su cika ba (ta amfani da hash checksum ko wasu hanyoyin) kafin canja wurin sarrafawa zuwa gare ta. Idan katangar taya ta gano duk wani cin hanci da rashawa a cikin babban BIOS, yawanci zai gargadi mai amfani cewa dole ne a fara aiwatar da dawo da shi ta hanyar booting daga kafofin watsa labarai masu cirewa (floppy, CD ko kebul na USB) don haka mai amfani zai iya gwada sake kunna BIOS. Wasu motherboards suna da *madadin* BIOS (wani lokacin ana kiranta da allon DualBIOS) don murmurewa daga cin hanci da rashawa na BIOS.

Farkon cutar ta BIOS ita ce BIOS Meningitis, wanda maimakon goge kwakwalwan BIOS ya cutar da su. BIOS Kwayar cuta ba ta da illa, idan aka kwatanta da ƙwayar cuta kamar CIH.

Cutar ta biyu ta BIOS ita ce CIH, wanda aka fi sani da “Cutar Chernobyl”, wacce ta sami damar goge abin da ke cikin filashin ROM ɗin a kan kwakwalwan kwamfuta masu jituwa. CIH ya bayyana a tsakiyar 1998 kuma ya fara aiki a watan Afrilu 1999. Sau da yawa, kwamfutocin da suka kamu da cutar ba za su iya yin taya ba, kuma dole ne mutane su cire filashin ROM IC daga motherboard su sake tsara shi. CIH ta yi niyya ga kwakwalwar kwakwalwar kwakwalwar Intel i430TX na lokacin sannan ta yi amfani da gaskiyar cewa tsarin aiki na Windows 9x, wanda kuma ya yadu a lokacin, ya ba da damar samun kayan aikin kai tsaye zuwa duk shirye-shirye.

Tsarin zamani ba shi da rauni ga CIH saboda nau'ikan chipsets da ake amfani da su waɗanda ba su dace da chipset na Intel i430TX ba, da ma sauran nau'ikan nau'ikan filashin ROM IC. Hakanan akwai ƙarin kariya daga sake rubutawa na BIOS mai haɗari a cikin nau'in tubalan taya wanda aka kiyaye su daga rubutaccen haɗari ko na biyu da tsarin sanye take da BIOS wanda zai iya, idan hadari, yayi amfani da madadin BIOS. Hakanan, duk tsarin aiki na zamani kamar FreeBSD, Linux, macOS, Windows NT -based Windows OS kamar Windows 2000, Windows XP da sabuwa, basa barin shirye -shiryen yanayin mai amfani don samun damar kayan aikin kai tsaye.

A sakamakon haka, kamar na 2008, CIH ya zama mara lahani, a mafi muni yana haifar da haushi ta hanyar cutar da fayilolin aiwatarwa da haifar da software na riga -kafi. Sauran ƙwayoyin ƙwayoyin cuta na BIOS suna kasancewa, duk da haka;  tunda yawancin masu amfani da gidan Windows ba tare da Windows Vista/7 na UAC suna gudanar da duk aikace-aikacen tare da gatan gudanarwa ba, ƙwayar cuta ta CIH ta zamani tana iya samun damar samun kayan aiki ba tare da fara amfani da amfani ba. Tsarin aiki na OpenBSD yana hana duk masu amfani samun wannan damar kuma grsecurity patch don Linux kernel shima yana hana wannan damar kayan aikin kai tsaye ta hanyar tsoho, bambancin kasancewa maharin da ke buƙatar mawuyacin matakin kernel amfani ko sake yin injin .

Cutar ta biyu ta BIOS wata dabara ce da John Heasman, babban mai ba da shawara kan harkokin tsaro na Babban Kwamitin Tsaro na Tsara na Burtaniya ya gabatar. A cikin 2006, a Taron Tsaro na Black Hat, ya nuna yadda ake ɗaukaka gata da karanta ƙwaƙwalwar jiki, ta amfani da hanyoyin ɓarna waɗanda suka maye gurbin ayyukan ACPI na yau da kullun da aka adana a ƙwaƙwalwar ƙwaƙwalwa. 

Cutar ta uku ta BIOS wata dabara ce da ake kira "Ciwon BIOS mai ɗorewa." Ya bayyana a cikin 2009 a Taron Tsaro na CanSecWest a Vancouver, da kuma Taron Tsaro na SyScan a Singapore. Masu binciken Anibal Sacco  da Alfredo Ortega, daga Fasahar Tsaro ta Core, sun nuna yadda ake saka lambar ɓarna a cikin ayyukan ɓarna a cikin BIOS, yana ba da damar kusan cikakken ikon sarrafa PC a farkon farawa, tun ma kafin a fara aiki da tsarin aiki. Tabbacin-ra'ayi baya amfani da aibi a aiwatar da BIOS, amma kawai ya ƙunshi hanyoyin walƙiyar BIOS na al'ada. Don haka, yana buƙatar samun dama ta zahiri ga injin, ko don mai amfani ya zama tushen. Duk da waɗannan buƙatun, Ortega ya jadadda babban tasirin abin da ya gano da Sacco: "Za mu iya facin direba don sauke cikakken tushen aiki. Har ma muna da ƙaramar lambar da za ta iya cirewa ko kashe riga -kafi. ” 

Mebromi trojan ne wanda ke kaiwa kwamfutoci da AwardBIOS, Microsoft Windows, da software riga -kafi daga kamfanonin China guda biyu: Rising Antivirus da Jiangmin KV Antivirus.    Mebromi yana shigar da tushen tushe wanda ke cutar da rikodin Jagora .

A cikin tattaunawar Disamba 2013 tare *da Minti 60*, Deborah Plunkett, Daraktan Bayar da Bayanai na Hukumar Tsaro ta Amurka ta yi ikirarin cewa NSA ta bankado tare da dakile yuwuwar harin BIOS da wata kasar wata kasa, ta nufi tsarin hada -hadar kudi na Amurka.  Shirin ya ambaci wasu majiyoyin da ba a san su ba suna zargin makircin China ne.  Koyaya labarin da ke biye a *The Guardian ,*  *The Atlantic ,*  *Wired*  da *The Register*  karyata ikirarin NSA.

Sabbin dandamali na Intel suna da fasahar Intel Boot Guard (IBG), wannan fasahar za ta duba sa hannu na dijital na BIOS a farawa, kuma an haɗa maɓallin jama'a na IBG a cikin PCH motherboard. Masu amfani na ƙarshe ba za su iya kashe wannan aikin ba.

## Madadin da magada
 
A shekara ta 2011, legacy PC BIOS an canza shi da Unified Extensible Firmware Interface (UEFI) a dayawan mashina. UEFI shi wani runtime na legacy BIOS. Tun farko Intel Itanium architecture ne suka kirkiro shi, UEFI yanzu ana samun sa don manhajan x86 da x86-64; kirkiran na musamman ya samo asali ne daga kampanin Unified EFI Forum, kamfanin Special Interest Group. EFI booting ya samo asli ne daga  Microsoft Windows versions domin taimakawa GPT, shiko Linux kernel 2.6.1, da macOS a Intel-based Macs a shekara ta 2014, sabon hadwe na comfuta aka samar masu da UEFI firmware. Ma zanin rootkit safeguard yana iya kare komfuta canza wa mmai amfani da ita sobtwe, wanda hakkan na sa UEFI ya shiga ma wuyacin yanayi open hardware.

Sauran madadin ayyukan “Legacy BIOS” a cikin duniyar x86 sun haɗa da coreboot da libreboot .

Wasu sabobin da wuraren aiki suna amfani da Firmware mai zaman kansa na dandamali (IEEE-1275) dangane da yaren shirye-shirye na Forth; an haɗa shi da kwamfutocin SPARC na Sun, layin IBM na RS/6000, da sauran tsarin PowerPC irin su motherboards na CHRP, tare da tushen OL8 XO-1 na x86.

Aƙalla aƙalla 2015, Apple ya cire tallafin BIOS na gado daga kwamfutocin MacBook Pro. Don haka mai amfani da BIOS baya goyan bayan zaɓin gado, kuma yana buga "Yanayin Legacy ba a tallafawa akan wannan tsarin". A cikin 2017, Intel ya ba da sanarwar cewa zai cire tallafin BIOS na gado daga 2020. Tun daga shekarar 2019, sabon dandamali na Intel OEM PCs baya goyan bayan zaɓin gado.

## Duba kuma

* Biyu taya
* e820
* Ƙarin Bayanin Kan Kan Tsarin Tsarin (ESCD)
* Input/Output Control System
* Babbar Kanfigareshi da Haɗin Wuta (ACPI)
* Jerin katsewa Ralf Brown (RBIL)katsewa, kira, musaya, tsarin bayanai, ƙwaƙwalwar ajiya da adiresoshin tashar jiragen ruwa, da opcodes masu sarrafawa don gine -ginen x86
* BIOS Management System (SMBIOS)
* Haɗin Haɗin Firmware Mai Haɗawa (UEFI)
* VESA BIOS Extensions (VBE)dubawa don amfani da allon bidiyo mai jituwa a manyan ƙuduri da zurfin bit, fiye da daidaitaccen tallafin BIOS

## Bayanan kula
 

## Manazarta