Xa isibini sabafundi sivavanya iskripti se-radio se-micro:bit sodwa edesikeni, phantse ngalo lonke ixesha siyasebenza. Xa izibini ezingamashumi amabini zivavanya esaa skripti sinye ngaxeshanye, inethiwekhi iyadilizwa: imiyalezo ifika emva kwemizuzwana, ifika ngamaxesha athile ingaqhelekanga, okanye inyamalale ngokupheleleyo. I-hardware ayaphukanga, yaye i-WiFi yesikolo ayiphazamisi. Iklasi yakho iqubisene ngqo nemiqobo emibini esisiseko yenethiwekhi: ukungqubana kweephakethi ezingalawulwayo (unthrottled physical packet collisions) kunye nokuzala kwesikhuseli sokufumana (receive-buffer flooding).

Iindawo Ezimbini Zomqobo Ezingabonakaliyo

Ukulungisa le ngxaki, kufuneka uqonde ukuba i-BBC micro:bit yenza ntoni ngenene xa iqhuba iibhloko ze-radio ze-MakeCode. I-micro:bit isebenzisa i-transceiver ye-Nordic Semiconductor (i-nRF51 kwi-v1, okanye i-nRF52 kwi-v2) esebenza kumaza e-2.4 GHz. Ngokumiselweyo (by default), isebenza ngaphandle kokujonga ukuba amaza akhululekile na (carrier-sensing handshake) okanye iprotokholi yokuzama kwakhona ngokuzenzekelayo (automatic retry protocol).

Xa iskripti sesifundo siyala i-micro:bit ukuba ithumele umqondiso, sidala iingxaki ezimbini ezicacileyo xa zininzi:

• Ukungqubana Kwamaza Emozulwini (Airtime Collisions): Ukuba ii-micro:bit ezimbini zithumela kumaza afanayo ngomzuzu omnye, imiqondiso yazo ye-radio iyadibana emoyeni. I-eriyeli efumanayo ichola umxube oxubeneyo nongacacanga wazo zombini ezo zithumelo. I-micro:bit ijonga i-Cyclic Redundancy Check (CRC) yephakethi, ifumanise ukonakala kwayo, ize iyilahle iphakethi ngokuthe cwaka. Akubikwa mposiso; idatha ivele inyamalale nje.
• Ukuphela Kwesikhuseli se-RX (RX Buffer Exhaustion): Inkqubo esebenzayo ye-software ye-micro:bit (CODAL / DAL) igcina iiphakethi ze-radio ezingenayo kwisikhuseli sokufumana esincinci esisekelwe kwi-hardware (receive buffer), ngokuqhelekileyo esithatha iiphakethi ezine kuphela ngaphambi kokuba sizidlulisele kwikhowudi yakho yomsebenzisi. Ukuba ii-micro:bit ezine zithumela imiyalezo ngelixa isixhobo esifumanayo sihlaziya umboniso waso wee-LED eziyi-5×5 okanye silinde ngaphakathi kwebhloko yokunqumama, eso sikhuseli sizala ngoko nangoko. Wonke umyalezo olandelayo ofika ngelo xesha uyalahlwa.

Eyona Ngxaki Yokwenene: Isantyalala se-Loop ye-"Forever"

Phantse kuwo onke amagumbi okufundela anale ngxaki, unobangela yipateni yekhowudi yabaqalayo ebonakala ngolu hlobo:

basic.forever(function () {
    radio.sendNumber(input.acceleration(Dimension.X))
})

Ngaphakathi kwe-loop eqhelekileyo ye-forever engenakulibaziseka kucacileyo, i-micro:bit iza kusasaza phakathi kweephakethi ezingama-30 nama-50 kumzuzwana ngamnye. Isibini esinye sabafundi esivelisa iiphakethi ezingama-40 ngomzuzwana sisebenzisa inxalenye encinci yamaza alapho. Xa uphindaphinda oko ngezibini ezilishumi elinesihlanu ezisebenza ngaxeshanye kwigumbi lokufundela elinye, ngequbuliso igumbi liza kugcwala ziiphakethi ezingama-600 ngomzuzwana.

Kuba ikhowudi esisiseko ye-radio ithumela imfamekile—oko kuthetha ukuba i-micro:bit ayilindi tshaneli icacileyo ngaphambi kokuthumela, yaye ayiceli siqinisekiso sokufika—ukusasaza ngesantya esiphezulu kuqinisekisa ukuba phantse lonke uthumelo luza kungqubana nephakethi yesinye isixhobo emoyeni.

Indlela Yokucwangcisa i-Radio Ethembekileyo Eklasini

Ukulungisa ukungathembeki kwe-radio akudingi iiprotokholi eziphambili zenethiwekhi. Kufuna kuphela iziseko ezine zokubhala ikhowudi eklasini.

1. Ungaze Usebenzise Iqela le-Radio Elimiselweyo

Izikhokelo zokufunda zihlala zixelela abafundi ukuba babhale radio.setGroup(1). Ukuba iklasi lonke lisebenzisa iqela 1, sonke isixhobo esifumanayo sisebenza ngeepakethi zesixhobo ngasinye esithumelayo, nokuba ungazihlaziya kamva kwi-software. I-MakeCode ixhasa amaqela ukusuka ku-0 ukuya ku-255. Ekuqaleni kwekota, nika idesika okanye isibini ngasinye inombolo yaso yeqela esisigxina:

• Isibini 1 sisebenzisa radio.setGroup(10)
• Isibini 2 sisebenzisa radio.setGroup(20)
• Isibini 3 sisebenzisa radio.setGroup(30)

Ii-ID zamaqela zitshintsha ubume bedilesi yenethiwekhi kutshiphu. Nangona amaqela asondeleleneyo asabelana ngendawo yetshaneli ye-2.4 GHz efanayo, ukucoca kwinqanaba ledilesi ye-hardware kuthintela iiphakethi ezingafunekiyo ekuzaliseni umgca wokufumana wesibini esingummelwane.

2. Valela Ii-Loop Ezingathintelwanga

Ngaphandle komsebenzi onqabileyo we-telemetry ye-physics esebenzisa amantshontsho aphakamileyo, phantse akukho projekthi yasesikolweni efuna uhlaziyo lwezihlandlo ezingama-50 ngomzuzwana. Imoto elawulwa kude (remote-control buggy) okanye isilawuli sokuthambeka siphendula ngokutyibilikayo kuhlaziyo lwezihlandlo ezi-5 ukuya kwezi-10 ngomzuzwana. Nyanzelisa unqumamo olucacileyo ngaphakathi kuyo yonke i-loop eqhubekayo yokuthumela:

basic.forever(function () {
    radio.sendValue("speed", currentSpeed)
    basic.pause(100) // ubuninzi buziiphakethi ezili-10 ngomzuzwana
})

Eyona nto ibhetele nangakumbi, suka ekuhloleni rhoqo (polling) uye kuthumelo oluqhutywa ziziganeko (event-driven transmission). Isilawuli kufuneka sisasaze kuphela xa umsebenzisi ecofa iqhosha, ethambekisa ngaphaya komlinganiselo obonakalayo, okanye xa sibona into ethintela indlela. Ukuba akukho nto itshintshileyo, i-radio kufuneka ithule.

3. Ngenisa Utshintsho Lwexesha (Timing Jitter)

Ukuba yonke i-micro:bit egumbini ithumela ncam emva kwemizuzwana eyi-100, iiwotshi zazo ekugqibeleni ziyahambelana ngqo—nto leyo ethetha ukuba izixhobo ezibini ziza kungqubana ngokuphindaphindiweyo kumjikelo ngamnye. Ungakuphelisa ukungqubana okucwangcisekileyo ngokongeza i-"jitter" engenangqiqo ecacileyo (pseudo-random) kukulibaziseka kwe-loop:

basic.pause(100 + Math.randomRange(0, 30))

Olu tshintsho luncinci lwemizuzwana eyi-0–30 luqinisekisa ukuba nokuba izixhobo ezibini zingangqubana kanye, uthumelo lwazo olulandelayo aluzi kungqamana ngexesha, nto leyo evumela iiphakethi ukuba zidlule kakuhle ngaphandle kokuphazamiseka.

4. Nciphisa Ubungakanani Beentlawulo Zedatha (Payloads)

Uthumelo lwe-radio luthatha ixesha lokwenene; okukhona iphakethi indala, kokukhona inkulu nethuba lokungqubana. I-MakeCode ikuvumela ukuba uthumele imitya emide yamagama nge-radio.sendString("FORWARD_LEFT"), kodwa imitya yamagama ithatha i-byte ezininzi. Endaweni yoko, sebenzisa amanani apheleleyo anocingo olunye okanye izibini zamaxabiso anoonobumba ababodwa:

Omele Ukukwenza Xa Iklasi Lonke Kufuneka Lithethe Nesixhobo Esifumanayo Esisinye

Kwizinto zokuvota zamaqela okanye ukugcinwa kwedatha yesikhululo semozulu, ii-micro:bit zabafundi ezilishumi elinesihlanu kufuneka zithumele idatha kwi-hub micro:bit enye. Olu lwakhiwo lusesichengeni kakhulu sokuwa kwesikhuseli (buffer collapse).

Ukwenza oku kusebenze ngaphandle kokulahleka kwedatha, guqula indlela yoqhagamshelwano: sebenzisa ulwakhiwo lokuhlola (polling architecture) endaweni yokusasaza okungena mida. I-micro:bit enguvimba ophakathi (central hub) isasaza isicelo se-ID ethile (umzekelo, ukuthumela inombolo 1). Sisixhobo somfundi kuphela esimiselwe njengesixhobo 1 esithumela i-payload yaso. Xa ifunyenwe, i-hub ibiza isixhobo 2. Olu lwakhiwo lwendlela yokutshintshiselana (round-robin) luphelisa ngokupheleleyo umngcipheko wokungqubana kwaye luqinisekisa ukuba i-micro:bit efumanayo ayize ibe nephakethi engaphezulu kwesinye elinde kwisikhuseli sayo ngexesha elinye.

Kwiinkqubo ezicwangcisiweyo ezilawula inqwaba yabafundi abakha iiprojekthi ze-hardware ezinxibeleleneyo kwinethiwekhi, Sheen Robotics icacisa ikharityhulam eyahlulwe ngokweemodyuli kunye nolungiselelo lwegumbi lokufundela nge-Infinity for Schools ukunceda ukugcina izifundo ezenziwayo ze-hardware ziqhuba ngendlela eqikelelekayo kunokuchitha ixesha usombulula iingxaki zokungqubana kwamaza angabonakaliyo.