Iphrothokholi ye-Modbus iwulimi lomhlaba wonke olusetshenziswa kuzilawuli zikagesi.Ngale phrothokholi, abalawuli bangakwazi ukuxhumana nabanye futhi namanye amadivayisi ngenethiwekhi (njenge-Ethernet).Sekuyizinga lemboni yendawo yonke.Le phrothokholi ichaza isilawuli esaziyo ngesakhiwo somlayezo esisetshenziswayo, kungakhathaliseki inethiwekhi abaxhumana ngayo.Ichaza indlela isilawuli esikucela ngayo ukufinyelela kwamanye amadivaysi, indlela yokuphendula izicelo ezivela kwamanye amadivaysi, kanye nendlela yokubona nokungena amaphutha.Icacisa i-schema sesizinda somlayezo kanye nefomethi evamile yokuqukethwe.Lapho uxhumana ngenethiwekhi ye-ModBus, le nqubo yomthetho inquma ukuthi isilawuli ngasinye sidinga ukwazi ikheli laso ledivayisi, sibone imilayezo ethunyelwe ngekheli, futhi sinqume ukuthi yiziphi izinyathelo okufanele zithathwe.Uma impendulo idingeka, isilawuli sikhiqiza umlayezo wempendulo futhi siyithumele sisebenzisa i-ModBus.Kwamanye amanethiwekhi, imilayezo equkethe iphrothokholi ye-Modbus iguqulelwa kuhlaka noma izakhiwo zephakethe ezisetshenziswa kuleyo nethiwekhi.Lolu shintsho luphinde lunwebe indlela eqondene nenethiwekhi yokuxazulula amakheli ezigaba, izindlela zomzila, nokutholwa kwamaphutha.Inethiwekhi ye-ModBus inomphathi oyedwa kuphela futhi yonke ithrafikhi iqondiswa nguye.Inethiwekhi ingakwazi ukusekela izilawuli zezigqila ezikude ze-247, kodwa inani langempela labalawuli bezigqila abasekelwayo lincike emishini yokuxhumana esetshenzisiwe.Ngokusebenzisa lolu hlelo, i-PC ngayinye ingashintshanisa ulwazi nomsingathi ophakathi ngaphandle kokuthinta i-PC ngayinye ukwenza imisebenzi yayo yokulawula.
Kunezindlela ezimbili ongakhetha kuzo ohlelweni lwe-ModBus: i-ASCII (ikhodi yokushintshana ngolwazi yaseMelika) kanye ne-RTU (Idivayisi Yesikhumulo Esikude).Imikhiqizo yethu ngokuvamile isebenzisa imodi ye-RTU ekuxhumaneni, futhi i-8Bit byte ngayinye emlayezo iqukethe izinhlamvu ezimbili ze-4Bit hexadecimal.Inzuzo eyinhloko yale ndlela ukuthi ingadlulisela idatha eyengeziwe ngesilinganiso se-baud efanayo kunendlela ye-ASCII.
Isikhathi sokuthumela: Jul-22-2022