Yintoni SPI-interface

SPI-interface waphuhliswa Motorola. Namhlanje yenye yezona ethandwa, ngenxa ngesantya esiphezulu kunye nokusebenziseka ezizodwa bonke abo ebhekisela uhlobo serial. Ukongeza, SPI-ujongano kwakhona umgaqo udibaniso. Ngokusisiseko, SPI i-logic data (master-slave) phakathi izixhobo ezimbini ezahlukeneyo. Iipropati Physical uhlawula ingqalelo ngaphantsi kakhulu ukuphumeza kuzo, njengoko bathi, "kwiimeko", ayithethi ukunika inqanaba protocol elisezantsi. umenzi nganye ungenza into ngokwabo.

SPI-interface inkcazelo

Nala isixhobo hlobo ugqithiselo lweengcombolo thotho lamazibuko (isuntswana kancinci). Xa utshatile kwaye ukufunda zihlukaniswe ngexesha yi umqondiso clock ekhethekileyo ibhasi ezizodwa (ebizwa ngokuba "ibhasi ixesha" okanye "sync"). Ngu okuhlamba kwakuthetha ukuba idatha sentlalo kunye nenkqubo Funda lwenzeka kwi malunga kumngcipheko ikloko eyenziwe ebhasini. Nale mbaxa ngokucacileyo ufundo ngolu hlobo ixesha kunye nezicwangciso, kuba kunokwenzeka ukuba usebenzise omnye nerejista okufanayo kokufumana kwaye edlulisa ulwazi. Kuyinto phantsi kwalo mgaqo kwaye livelise i-SPI-interface. Nangona kunjalo, uphuhliso zobugcisa hayi umi kunjalo, ngenxa mali elikhulu imemori ekwalelayo iingxaki, kwaye uninzi izixhobo kufuneka eyahlukileyo igalelo kunye output iirejista. Apha Ngamafutshane siye ingqalelo indlela wacwangcisa SPI interface.

Inkcazelo yokusebenza device

Isixhobo odala pulses iwotshi (ulawulo) ukuya ixesha ibhasi, i "inkosi" (master). Esi sixhobo elawula inkqubo yonke kunaniselwano data, okt, simisela ukuba uqale nini exchange, xa nakugqiba, zingaphi wayemana transfer ulwazi njalo .. Isixhobo yesibini inxaxheba kutshintshiselwano, ebizwa ngokuba "khoboka." Esi sixhobo ayikho nangayiphi na indlela kuchaphazela wotshi ibhasi. Kuba exchange full-kabini (okudlulisela kumacala omabini ngexesha elinye) SP- ujongano usebenzisa imigca emine:

- Mosi - igalelo kunye neziphumo we inkosi khoboka. Kwakule mbono kukho ukudluliselwa kolwazi ukusuka umkhosi ukuya receiver.

- MISO - master igalelo nemveliso "khoboka." Yi le nto inkosi ifumana idata esuka isixhobo abangabancedani.

- SCLK - clock ibhasi. Kwakule mbono, i "bakhokelayo" isixhobo yenza pulses iwotshi.

- SS - ukhetho "khoboka." Nale inkosi wire olawula iseshoni exchange.

amanqanaba logic-zero ukuba ikhodi, kwaye ixabiso ombane unit kwi data ibhasi (MISO kunye Mosi). I-SS signal lubonisa isiphelo kunye ukuqala iseshoni ye ulwazi lonaniso. Amaninzi oko yabaxwa. Oku kuthetha ukuba ngethuba exchange data "inkosi" isixhobo kufuneka ifakwe kumgca SS uphawu kwinqanaba elisezantsi, yaye ekupheleni okunanisa - phezulu. Ubukho yokosulela SS-level ivumela ukuba amalungiselelo izixhobo ezininzi "khoboka" esebenzisa umqondiso iwotshi kunye data ibhasi ngaphandle elandelwayo ezongezelelweyo. Noko ke, xa loo uqhagamshelo kuyimfuneko ukuba unikeze i isixhobo kumaza kwilayini nganye eyahlukileyo SS.