Iine yakakura uye yakagadziridzwa SCM tekinoroji mukutanga 80's, musika wepasirese wezviridzwa unongogarwa nemamita akangwara, ayo anokonzerwa nezvinodiwa zveruzivo rwebhizinesi.Imwe yemamiriro ezvinhu akakosha kuti mabhizinesi asarudze mita kuve netiweki yekukurukurirana interface.Iyo yekutanga data analog chiratidzo chekubuda inzira iri nyore, ipapo chiridzwa chekushandisa iRS232 interface, iyo inogona kuzadzisa point-to-point kutaurirana, asi nzira iyi haigone kuita networking basa, ipapo kubuda kweRS485 kunogadzirisa dambudziko iri.
RS485 chiyero chinotsanangura hunhu hwemagetsi evatyairi uye vanogamuchira mune yakaenzana dhijitari multipoint masisitimu.Iyo chiyero inotsanangurwa neTelecommunication Indasitiri Association uye Electronics Indasitiri Union.Digital communication network uchishandisa iyi chiyero inogona kunyatso fambisa masaini pamadaro marefu uye munzvimbo ine ruzha rwemagetsi.RS-485 inoita kuti zvikwanisike kugadziridzwa kwekubatanidza manetwork emunharaunda pamwe neakawanda mabazu ekutaurirana.
RS485ine marudzi maviri ewaya maviri ewaya system uye mana waya system.Ina waya system inogona chete kuwana point-to-point yekukurukurirana modhi, isingawanzo shandiswa.Maviri waya system wiring mode anowanzo shandiswa nebus topology chimiro uye anogona kubatana ne32 node zvakanyanya mubhazi rimwe chete.
Muiyo RS485 yekutaurirana network, iyo main-sub kutaurirana inowanzoshandiswa, kureva kuti, mita huru yakabatana neakawanda sub metres.Muzviitiko zvakawanda, kuwirirana kweRS-485 yekukurukurirana link inongobatanidzwa nepeya yakamonyoroka ye "A" uye "B" kuguma kwega yega interface, asi uchiregeredza chiratidzo chepasi.Iyi nzira yekubatanidza muzviitiko zvakawanda inogona kushanda zvakajairika, asi yakaviga njodzi huru yakavanzika.Chimwe chezvikonzero chakajairika kukanganiswa kwemodhi: RS - 485 interface inotora nzira yekusiyanisa nzira uye haidi kuona chiratidzo ichipokana nechero referensi, asi kuona musiyano wevoltage pakati pewaya mbiri, izvo zvinogona kutungamira mukusaziva kweyakajairika mode voltage. range.Iyo RS485 transceiver common-mode voltage ranges pakati - 7V uye + 12V uye network yese inogona kushanda zvakajairika, chete kana ichisangana nemamiriro ari pamusoro,;Kana iyo yakajairwa modhi voltage yetiweki mutsara ichipfuura iyi chiyero, kugadzikana uye kuvimbika kwekutaurirana kuchakanganiswa, uye kunyangwe iyo interface ichakuvadzwa.Chikonzero chechipiri idambudziko reEMI: iyo yakajairika-modhi chikamu cheinobuda chiratidzo chemutyairi anotumira inoda nzira yekudzoka.Kana pasina yakaderera kuramba nzira yekudzoka (signal ground), inodzokera kutsime nenzira yemwaranzi, uye bhazi rese rinopenya mafungu emagetsi kunze senge antenna hombe.
Yakajairika serial yekutaurirana zviyero ndeye RS232 uye RS485, iyo inotsanangura voltage, impedance, nezvimwewo, asi haitsanangure software protocol.Yakasiyana neRS232, RS485 maficha anosanganisira:
1. Magetsi maitiro eRS-485: logic "1" inomiririrwa nemusiyano wemagetsi pakati pemitsara miviri se + (2 — 6) V;Zvinonzwisisika "0" inomiririrwa nemusiyano wevoltage pakati pemitsara miviri se - (2 - 6) V. Kana iyo interface chiratidzo chiyero chakaderera pane RS-232-C, hazvisi nyore kukuvadza chip cheiyo interface yedunhu, uye iyo nhanho inoenderana neiyo TTL nhanho, saka zviri nyore kubatana neTTL dunhu.
2. Nhamba yepamusoro yekufambisa data yeRS-485 ndeye 10Mbps.
3. RS-485 interface yakasimba, ndiko kuti, yakanaka anti-ruzha kupindira.
4. Iyo yakakura yekufambisa kureba kweRS-485 interface ndeye 4000 tsoka chiyero kukosha, chokwadi inogona kusvika 3000 metres (theoretical data, mukushanda kunoshanda, muganhu nhambwe inongosvika anenge 1200 metres), mukuwedzera, RS-232. -C interface inongobvumira kubatanidza 1 transceiver mubhazi, kureva, iyo imwechete chiteshi.Iyo RS-485 interface mubhazi inobvumirwa kubatanidza kusvika ku128 transceivers.Ndiko kuti, nekwakawanda-zviteshi kugona, vashandisi vanogona kushandisa imwechete RS-485 interface kumisa nyore network yemidziyo.
Nekuti RS-485 interface ine yakanaka anti-ruzha kupindira, izvo zviri pamusoro zvakanakira zvehurefu hwekutapurirana chinhambwe uye akawanda-zviteshi kugona zvinoita kuti ive inofarirwa serial interface.Nekuti iyo hafu-duplex network inoumbwa neRS485 interface inowanzongoda waya mbiri chete, iyo RS485 interface inotora yakavharidzirwa yakamonyoroka kutapurirana.Iyo RS485 interface yekubatanidza inoshandisa 9-core plug block yeDB-9, uye yakangwara terminal RS485 interface inoshandisa DB-9 (gomba), uye keyboard interface RS485 yakabatana nekhibhodi inoshandisa DB-9 (tsono).
Nguva yekutumira: Mar-15-2021