Lapho abafundi abayishumi bexhuma ama-microcontroller ku-USB hub yedeskithophu ekuqaleni kwesifundo sokubhala amakhodi bese yonke idivayisi inyamalala ku-IDE, inkinga akulona iphutha lesofthiwe (software bug) noma i-driver engasebenzi. Kuyinkinga kagesi (electrical trip). Ukuxhunywa ngasikhathi sinye kwamabhodi amaningi okuthuthukisa kudonsa umsinga wogesi ongenayo ngamandla ngokuphazima kweso—obizwa nge-inrush current—okwenza i-voltage ye-USB rail yehle ngaphansi kwezinga elidingekayo lokusebenza. Ukuvikela i-motherboard yekhompyutha ekulimaleni ngokomzimba, i-host USB controller isetha kabusha yonke i-bus, inqamule ngokushesha konke ukuxhumana kwe-serial kuyo yonke i-hub.

Ukusebenza Kwe-Inrush Current Emabhodini Okuthuthukisa

Leli nalelo bhodi lokuthuthukisa le-microcontroller—kungaba yi-Arduino Uno, i-ESP32, i-Raspberry Pi Pico, noma i-micro:bit—liqukethe amasekethe alawula amandla kagesi (power regulation circuitry). Kuzo zonke izinsimbi zamandla ezingu-5V kanye nezingu-3.3V kuhlala ama-decoupling kanye nama-bulk capacitor. Lawa ma-capacitor asebenza njengezinqolobane ezincane zamandla zasendaweni eziklanyelwe ukulinganisa ukuntengantenga okusheshayo kwe-voltage lapho umsakazo we-microcontroller usakaza noma lapho i-LED esebhodini ivuleka noma icisha.

Lapho ibhodi elingenawo amandla lixhunywa embobeni ye-USB esebenzayo (isenzakalo se-hot-plug), ama-capacitor alo angenawo amandla aziphatha okwesikhashana njenge-short circuit kagesi. Engxenyeni encane ye-millisecond, ibhodi lidonsa amandla aphindaphindwe kaningi kunomsinga walo ovamile wokusebenza ngenkathi lawo ma-capacitor esashajelwa ku-voltage yomzila. Ibhodi elilodwa elidonsa igagasi elisheshayo lika-1.5A kuya ku-2A ama-microsecond ambalwa lisingathwa kalula ukulawulwa kwamandla kwekhompyutha yokusingatha. Nokho, lapho abafundi abayisishiyagalombili, abayishumi, noma abayishumi nambili bexhuma amabhodi ngaphakathi kwemizuzwana emihlanu efanayo ekuqaleni kwekilasi, isidingo esihlanganisiwe se-inrush current siyehlula umugqa wokuhlinzeka ngamandla.

Indlela Ama-Host USB Controller Asabela Ngayo Ekwehleni Kwe-Voltage

Ukucaciswa kwe-USB 2.0 kudinga ukuthi imbobo yokusingatha igcine i-bus voltage phakathi kuka-4.75V kanye no-5.25V ngaphansi komthwalo. Lapho igagasi elikhulu elihlanganisiwe le-inrush lishaya isiphehli samandla esinganele, i-bus voltage yehla kakhulu ngaphansi kuka-4.5V.

Ama-PC edeskithophu kanye nezinqola zamalaptop zasesikoleni ziqapha lo mzila zisebenzisa amaswishi azinikele okusabalalisa amandla noma ama-polyfuse e-hardware ku-motherboard. Lapho i-controller ibona isimo sokushoda kwe-voltage (undervoltage) noma ukweqa kwamanje (overcurrent), iqalisa ukulandelana kokuzivikela:

• Ukucinywa kwe-VBUS (VBUS Cutoff): I-host controller iphazamisa okwesikhashana umugqa wokuhlinzeka ngo-5V ukuze icime iphutha elibonakele.
• Ukusetha Kabusha Kwe-Controller (Controller Reset): I-host controller isetha kabusha i-root hub yayo yangaphakathi. Ku-Windows, lokhu kuvame ukuvela njengekhodi yephutha 43 (error code 43), isaziso esithi "idivayisi ye-USB ayaziwa", noma ukunyamalala buthule kwazo zonke izimbobo ze-virtual COM ezabiwe.
• Ukwehluleka Kwe-Enumeration (Enumeration Failure): Lapho amandla ebuyiselwa, wonke amabhodi ayishumi azama ukuxoxisana kabusha ngokuxhumana kwawo kwe-USB ngasikhathi sinye. Ulayini we-enumeration wesistimu yokusebenza uba mkhulu kakhulu, okuholela ezicelweni ezingaphelele zezincazelo namabhodi ahlulekayo ukuvela kubahleli abasuselwa kumabhuloki noma emibhalweni.

Inkinga Ngama-Hub Avamile Aseklasini

Amakilasi avame ukuthembela kuma-USB hub ajwayelekile anezimbobo eziningi aklanyelwe izinto ezisetshenziswa ehhovisi ezingadonsi amandla amaningi njengamagundane, amakhibhodi, nama-flash drive. Elebhu ye-robothikisi, lawa ma-hub ahluleka ngenxa yezizathu ezimbili zesakhiwo:

1. Ama-Hub Angenawo Amandla Angaphandle (Passive / Bus-Powered Hubs)

I-hub engenawo amandla angaphandle ithola ubukhulu obungu-500mA (USB 2.0) noma 900mA (USB 3.0) embobeni eyodwa yekhompyutha yokusingatha bese ihlukanisa lowo msinga kuzo zonke izimbobo ezisezansi. I-ESP32 eyodwa ene-Wi-Fi esebenzayo noma i-micro:bit esebenzisa inzwa yangaphandle ingadonsa kalula u-150mA kuya ku-300mA iyodwa. Ukuzama ukusebenzisa ama-microcontroller ayishumi embobeni eyodwa engenamandla angaphandle ukwehluleka kwezibalo okusheshayo.

2. Ama-Hub Ashibhile Anamandla Angaphandle (Cheap Externally Powered Hubs)

Ama-hub amaningi ashibhile anikwa amandla afika ne-adapter yamandla yangaphandle engu-5V 2A kanye nebhodi lesekethe elimane lixhume zonke izikhonkwane zamandla eziyishumi ze-USB 5V ngokuqondile kumzila wamandla owabiwe, ongenaso isivikelo (unbuffered rail). Ngenkathi i-adapter yamandla ihlinzeka ngomsinga owanele oqhubekayo wamabhodi angenzi lutho, ayinawo amandla aguqukayo okuletha amandla kanye nokulawulwa kwembobo ngayinye okudingekayo ekusetshenzisweni kwaseklasini. Ngenxa yokuthi zonke izimbobo zabelana ngomugqa ofanayo wethusi, igagasi le-inrush noma i-short-circuit ye-breadboard kuMbobo 3 izokwehlisa ngokushesha i-voltage eziMbobeni 1 kuye ku-10, iphazamise ukuxhumana kwawo wonke umuntu.

Yini Exazulula Ukunqamuka: Ukuhlukaniswa Kokweqa Kwamanje Ngembobo Ngayinye

Ukuqeda ukunqamuka kokuxhumana elebhu enabafundi abangama-30 kuya kwabangama-40, i-hardware ye-USB kufanele ihlangabezane nezidingo ezintathu zobunjiniyela ezingaxoxiswana ngazo:

• Ukushintshwa Kwamandla Embobeni Ngayinye: I-hub kufanele ibe nezilawuli ezizimele zokusabalalisa amandla (noma ama-fuse kagesi asheshayo) embobeni ngayinye esezansi. Uma umfundi edala i-short ngengozi ku-breadboard yakhe noma exhuma umthwalo one-capacitance ephezulu, kuvaleka leyo mbobo ethile kuphela. Ezinye izisetshenziswa eziyisishiyagalolunye ziyaqhubeka nokuxhumana ngaphandle kokuphazamiseka.
• Usayizi Owanele Wesiphehli Samandla: Ku-hub ye-USB 2.0 enezimbobo eziyishumi, i-adapter yamandla yangaphandle kufanele ihlinzeke okungenani ngo-5V 5A (25W) wamandla angempela ngemva kokulahleka kokuguqulwa, okuqinisekisa u-500mA ohlanzekile, oqhubekayo embobeni ngayinye kungakhathaliseki ukuthi yini esebenza ku-silicon.
• Izilawuli Zezimpande Zokusingatha Ezizimele: Ama-motherboard esimanje abelana ngezilawuli zezimpande ze-USB zangaphakathi ezimbobeni eziningi zangaphandle zekhompyutha. Ukusabalalisa ama-hub anikwe amandla anezimbobo eziningi kuzilawuli ezihlukene ze-USB kukhompyutha kuvimbela ukuvaleka ngokuphelele kwe-bus yesistimu.

Uma ukhetha i-hardware yelebhu entsha noma ushintsha okokusebenza kwedeskithophu okuvame ukufeyila, i-Sheen Robotics ihlinzeka nge-hardware ehloliwe yaselebhu eklanyelwe imithwalo yaseklasini ngokusebenzisa izixazululo zethu zokuthola okokusebenza kwelebhu.

Izindlela Zokusebenza Zesikhashana Aseklasini

Uma kufanele usebenze ngama-hub akhona, angahlukanisiwe kuze kufakwe i-hardware engcono, sebenzisa lezi zinqubo ezingokoqobo ukuze unciphise ukunqamuka phakathi nesifundo:

• Ukuxhuma Ngezikhathi Ezihlukene: Yalela abafundi ukuthi baxhume ama-microcontroller abo umugqa owodwa ngesikhathi kuhlale isikhashana semizuzwana emihlanu phakathi kwamaqembu ukugwema amagagasi e-inrush ahlangene.
• Amandla Angaphandle E-actuator: Ungalokothi uvumele abafundi ukuthi baphakele amamotho amancane e-DC, ama-servo, noma amamojula e-buzzer an किला amandla amakhulu ngokuqondile kusuka kuphini le-5V lebhodi lokuthuthukisa nge-USB. Sebenzisa amaphekhi amabhethri angaphandle e-4xAA anomhlabathi ofanayo (common ground) wamandla e-actuator ukuze ugcine umsinga we-USB bus ukhawulelwe ngokuphelele ku-logic yama-microcontroller.
• Nciphisa Ukulayishwa Kwe-Hub Emabhodini Ama-4: Hlukanisa ama-hub ajwayelekile anezimbobo eziyi-10 ngokuxhuma embobeni eyodwa ulande enye, bese usabalalisa amanye amabhodi ngokuqondile ezimbobeni zangemuva ze-I/O zekhompyutha.