Unxibelelwano lweModbus: Isihluthulelo sokwakha iiNethiwekhi zeShishini ezingenamthungo
Unxibelelwano lweModbus: Isihluthulelo sokwakha iiNethiwekhi zeShishini ezingenamthungo
Isishwankathelo
I-Modbus yiprotokholi esetyenziswa kakhulu kwicandelo lemizi-mveliso, eyaphuhliswa ngo-1979 ukuze kuvunyelwe unxibelelwano phakathi kwezixhobo ezizenzekelayo. I-Modbus yaqala ukusetyenziswa njengeprotokholi yenqanaba lesicelo sokudlulisa idatha kusetyenziswa umaleko we-serial, kwaye ngoku inokwandiswa ukuze isetyenziswe nge-serial, TCP/IP, kunye ne-User Datagram Protocol (UDP). Olu xwebhu lubonelela ngengcaciso enzulu yokuphunyezwa kweprotokholi.
Yintoni iModbus protocol?
I-Modbus yinkqubo yokuphendula isicelo esetyenziswa ngobudlelwane phakathi kwenkosi nekhoboka. Kubudlelwane phakathi kwenkosi nekhoboka, unxibelelwano luhlala lusenzeka ngababini (isixhobo kufuneka siqalise isicelo size silinde impendulo), kwaye isixhobo esicelayo (isixhobo esiyintloko) sinoxanduva lokuqalisa ukusebenzisana ngakunye. Ngokwesiqhelo, isixhobo esiphambili sisixhobo esisebenzisana nomntu nomatshini (i-HMI) okanye inkqubo yokubeka esweni kunye nokufunyanwa kwedatha (i-SCADA), ngelixa izixhobo zesibini zizinzwa, abalawuli be-logic abacwangcisiweyo (i-plcs), okanye abalawuli be-automation abanokucwangciswa (ii-PAC). Umxholo wezi zicelo kunye neempendulo, kunye nomaleko wenethiwekhi othumela le miyalezo, uchazwa ziileya ezahlukeneyo zeprotocol.
Zeziphi izixhobo ezixhasa iprotocol yeModbus?
Iprotokholi yeModbus ixhaswa kakhulu zizixhobo, kuquka ii-programmable logic controllers (PLCs), ii-remote terminal units (RTUs), ii-sensors, ii-actuators, ii-human-machine interfaces (HMIs), kunye nezinye iintlobo ezininzi zezixhobo kwi-industrial automation kunye ne-industrial fields. ISebe loLawulo lweeNkqubo. I-Modbus isetyenziswa kakhulu kwaye ibe ngumgangatho oqhelekileyo wokusebenzisana phakathi kwezixhobo ezenziwe ngabavelisi abahlukeneyo kwiinkalo ezifana nokuvelisa, amandla, ukuthutha, kunye ne-automation yezakhiwo.
Isango leModbus sisixhobo esiguqula iprotocol yonxibelelwano esetyenziswa zii-hubs zenethiwekhi yeenkqubo ze-automation zemizi-mveliso. Sinxibelelana nezixhobo ezikrelekrele, siqokelele idatha kwizixhobo ezisezantsi size siyithumele kwisango leModbus, siseka unxibelelwano nenethiwekhi yekhompyutha ephezulu, kwaye senze iprotocol yeModbus neekhompyutha zenethiwekhi.
Imo yonxibelelwano lweModbus
Iprotokholi yeModbus ineendlela ezintathu eziphambili zonxibelelwano:
lI-RTU (Iyunithi yeSitimela esikude)
lI-ASCII (iKhowudi eMigangatho yaseMelika yokuTshintshiselana koLwazi)
lI-TCP/IP (iProtokholi yoLawulo loThutho/iProtokholi ye-Intanethi)
Kwiprotokholi yeModbus, iModbus TCP kunye neModbus RTU zezona ndlela zimbini zixhaphakileyo zonxibelelwano. Nangona zonke zenzelwe ukwenza kube lula ukutshintshiselana ngedatha phakathi kwezixhobo, kukho umahluko omkhulu kwiindlela zazo zokusebenzisa kunye neemeko zokusetyenziswa.
Indlela yonxibelelwano kunye nesantya
I-Modbus TCP isebenzisa i-TCP/IP protocol stack ukudlulisa idatha kwiinethiwekhi, ixhomekeke kwiziseko zenethiwekhi ezifana ne-Ethernet ukufezekisa ukuhanjiswa kwedatha ngesantya esiphezulu nangomlinganiselo omkhulu.
Kwelinye icala, iModbus RTU idlulisela idatha ngemigca elandelelanayo efana neRS-485 kunye neRS-232, enesantya esicothayo sokudlulisela idatha..
I-Modbus RTU ihlanganisa iifreyimu zedatha kwifomathi encinci ye-binary, kuquka ii-address fields, ii-function codes, idatha, kunye nee-checksum fields. Le fomathi idluliselwa ngokufanelekileyo kwifomu ye-binary, nto leyo eyenza ukuba ifaneleke ngakumbi kwizicelo zolawulo lwexesha langempela okanye lwengingqi, ingakumbi kwiindawo ezingenazo iziseko zenethiwekhi ezikhoyo, ezifana neendawo zokwenza izinto ngokuzenzekelayo kwimizi-mveliso, iinkqubo ezifakiweyo, iinethiwekhi ze-sensor, kunye neenkqubo zolawulo ezincinci.
Kwelinye icala, iModbus TCP iguqula i-byte nganye yedatha ye-binary ibe yintambo ye-hexadecimal enamanani amabini asisigxina, ethi emva koko idityaniswe kunye ize idluliselwe kwifomathi yekhowudi ye-TCP. Ngenxa yobulula bayo, ukuthembeka kwayo, kunye nokusebenza kakuhle kweendleko, isetyenziswa kakhulu kwiinkqubo ezinkulu zokwenza izinto ngokuzenzekelayo, amaziko edatha, ukwenza izinto ngokuzenzekelayo kwizakhiwo, kunye ne-intanethi yezinto zemizi-mveliso, ezifuna umgama omde wonxibelelwano kunye neemfuno eziphezulu zexesha langempela kunye nozinzo lokudlulisela idatha.
Aindawo yokusetyenziswa
Kwishishini lokuvelisa, iModbus isetyenziselwa ukuqhagamshela izixhobo ezahlukeneyo zemveliso kunye nokufezekisa ukujonga nokulawula inkqubo yemveliso ngexesha langempela; Kwicandelo lamandla, isetyenziselwa ulawulo lweenkqubo zamandla ezizenzekelayo, kubandakanya ukuveliswa kombane, ukuhanjiswa, kunye neenkqubo zokusasazwa; Kwishishini lokuthutha, iModbus isetyenziselwa iinkqubo zesignali zothutho lwezitimela zasezidolophini, ukujonga imeko yesithuthi, njl.njl. Kwicandelo le-automation yesakhiwo, iModbus isetyenziswa kwi-HVAC, izibane, kunye neenkqubo zokhuseleko kwizakhiwo.
Ngophuhliso lwetekhnoloji ye-Intanethi yemizi-mveliso kunye ne-Intanethi yezinto, iModbus ikwaphucula rhoqo ukuze ivumelane neemeko ezinzima nezitshintshayo zoshishino. Umzekelo, iModbus/TCP kancinci kancinci iba ngumgangatho oqhelekileyo wonxibelelwano lwe-Ethernet yemizi-mveliso, kwaye izixhobo zesango ezisekelwe kwiModbus zivumela izixhobo zemveli zeModbus ukuba ziqhagamshelane ngokulula neenethiwekhi zanamhlanje, zivumela ukugcinwa kwelifu kunye nohlalutyo lwedatha.
Ngamafutshane, iModbus, njengenkqubo yonxibelelwano lwemizi-mveliso evuthiweyo nesetyenziswa kakhulu, ibone inkqubela phambili yetekhnoloji yokuzenzekela kwemizi-mveliso yaza yabeka isiseko esiqinileyo sobukrelekrele bemizi-mveliso bexesha elizayo. Ngophuhliso oluqhubekayo lwetekhnoloji, iModbus iya kuqhubeka nokudlala indima ebalulekileyo ekuqhubeni ubuchule kunye notshintsho kwicandelo lemizi-mveliso.okanye.