RS-485 kugwirizana ndi ulamuliro

RS-485 ndi muyezo umene anali woyamba anatengera mu Intaneti Makampani Association. Pakali pano, amachita izi Standard ndi makhalidwe magetsi a mitundu yonse ya amalandira ndi transmitters ntchito zosiyanasiyana machitidwe oyenera yadigito.

Ndi chiyani icho?

Mwa akatswiri RS-485 ndi dzina mwachilungamo otchuka wa mawonekedwe, amene chimagwiritsidwa ntchito mu machitidwe osiyanasiyana mafakitale ndondomeko kulamulira kwa kulumikiza opha angapo komanso zosiyanasiyana zipangizo zina pakati pawo. Chachikulu kusiyana pakati pa mawonekedwe wa ang'onong'ono wamba RS-232 ndi kuti amapereka ukwati pa nthawi yomweyo wa mitundu yambiri ya zipangizo.

Kugwiritsa RS-485 amaperekedwa ndi kuwombola mkulu-liwiro la mudziwe mwa zipangizo angapo kudzera lokhala ndi waya kulankhulana kugwirizana mu mode theka duplex. Ambiri ntchito mafakitale zamakono mu ndondomeko ya ma PC.

Uthunthu ndi liwiro

Mwa mfundo imeneyi zimatheka kuulutsa nkhani pa liwiro 10 Mbit / s, pamene pazipita zotheka osiyanasiyana utsogoleri zimadalira liwiro limene deta zimafalitsidwa. Choncho, kuonetsetsa pazipita deta liwiro akhoza opatsirana si zoposa 120 m, pamene pa liwiro la 100 kbit / s mudziwe ukufalitsidwa mamita oposa 1200.

Number chipangizo kaphatikizidwe

Chiwerengero cha zipangizo kuti akhoza kuphatikiza ndi RS-485 mawonekedwe utsogoleri zimadalira transceivers zimene chipangizo ntchito. Aliyense chopatsilira lakonzedwa kuti ulamuliro munthawi yomweyo 32 ndi amalandira muyezo, koma ayenera kumvetsa kuti pali amalandira, athandizira impedance ndi 50%, 25% kapena gawo ngakhale ang'onoang'ono a muyezo, ndi vuto la kugwiritsa ntchito zida ngati chiwerengero cha zipangizo zingawonjezere mogwirizana.

Zolumikizira ndi ndondomeko

RS-485 chingwe si yovomerezeka ena mafelemu mtundu deta kapena protocol. Nthawi zambiri zaphindu kwa deta ntchito ndendende mafelemu yemweyo, amene amagwiritsa RS-232, i.e. ndi Tinthu deta, chiyambi ndi kusiya Akamva, ndi parity Akamva, ngati n'koyenera.

ndondomeko kulankhulana ntchito mu kachitidwe kamakono kwambiri ikuchitika pa "mbuye-kapolo", ndiye, ena amtundu chipangizo pa maukonde ndi kutsogolera ndi adzatenge pempholi kuwombola potumiza kanthu mwa zipangizo zonse kapolo amasiyana maadiresi zomveka. The protocol wotchuka kwambiri lero ndi Modbus RTU.

Dziwani kuti RS-485 chingwe ali zina mtundu wa zolumikizira kapena soldered, ndiko kuti, angayambe achepetsa zolumikizira, ndi DB9 ndi ena.

kugwirizana

Nthawi zambiri ntchito mawonekedwe izi akukumana maukonde m'deralo, chomwe chili transceivers angapo.

Zikugwira RS-485 kugwirizana, muyenera mwaluso zimagwirizizirana ndi aliyense madera ena mbendera, zafala monga A ndi B. Mu nkhani iyi, kusintha osati loopsa, zipangizo chabe chikugwirizana sizigwira ntchito.

Malangizo

Ntchito mawonekedwe RS-485, muyenera kuganizira zinthu zingapo ntchito yake:

• Malo ambiri mulingo woyenera kufala chizindikiro - ndi chingwe cha nsapato zopotoka.
• chingwe malekezero kwenikweni muyenera kuti tisiye mothandizidwa ndi resistors apadera osachiritsika.
• Network, amene amagwiritsa muyezo kapena USB RS-485, ayenera kukonza popanda nthambi iliyonse basi mtunda.
• zipangizo ayenera olumikizidwa kwa mawaya chingwe yaifupi ngati nkotheka.

Pankhaniyi, yabwino yothetsera kuti pakhale RS-485 mawonekedwe, - ndi awiri opiringizika, monga kumasiyana asang'ambe parasitic chizindikiro cha kutentha, ndipo ali ndi chitetezo chabwino kwambiri ku kusokonezedwa. Ngati zipangizo ntchito pansi kwambiri mkulu kunja phokoso, ndi bwino kugwiritsa ntchito chingwe ndi, isagwe zopotoka awiri, pamodzi ndi nthaka zoteteza ndi chishango chingwe.

mgwirizano

Kudzera osachiritsika resistors muyezo kapena USB RS-485 amapereka kugwirizana kwathunthu mapeto lotsegula la mzere chingwe akutsatiridwa ndi kuthetseratu kuthekera chinyezimiro chizindikiro.

Standard kukana resistors n'koyenera khalidwe impedance a chingwe ndi anthu zingwe zimene zochokera zopotoka-awiri chingwe, nthawi zambiri, ndi zaphindu pafupifupi 100-120 ohms. Mwachitsanzo, mwachilungamo otchuka lero UTP-5 chingwe, chimagwiritsidwa ntchito Efaneti kuika ndondomeko ali ndi impedance khalidwe la 100 ohms. Kuti muwone ena chingwe angagwiritsidwe ntchito ndi chipembedzo china chilichonse.

Resistors, ngati n'koyenera, zikhoza losindikizidwa pa zikhomo chingwe cholumikizira kale chipangizo chomaliza. Kawirikawiri resistors amene anaika mu chipangizo, kotero kuti kugwirizana resistor n'kofunika kuti kukhazikitsa jumper. Pankhaniyi, ngati mwachita foni kwathunthu rassoglasovyvaetsya mzere. Ndipo pofuna ntchito wabwinobwino wa dongosolo, muyenera kugwirizana ndi ofananira kapu.

misinkhu mbendera

RS-485 akugwiritsa ntchito moyenera dera deta wailesi, ndiye amaudindo voteji pa chizindikiro mizere A ndi B zimasiyana wotsutsana.

Kudzera sensa kuyenera kuchitika m'njira mlingo chizindikiro cha 1.5 pa katundu zonse, ndi zosaposa 6 Ngati pamene chipangizo ndi kusakhala ndi chochita. Mlingo voteji chimaonekera differentially wachibale aliyense mzere wina chizindikiro.

Kodi wolandirayo ndi osachepera analandira chizindikiro mlingo Mulimonsemo ayenera kukhala pa mlingo osachepera 200 MV.

kusamutsidwa

Ngati pamene palibe chizindikiro pa mizere mbendera, pang'ono kuchepetsa kumachitika, zomwe secures chitetezo wolandila ndi positives onyenga.

Akatswiri amalangiza kuchita kuchepetsa zikuluzikulu pang'ono kuposa 200 MV, kuyambira mtengo uwu lolingana zone kusadalirika muyezo athandizira chizindikiro. Pankhaniyi, unyolo wina anakoka kuti mzati zabwino gwero lake, pamene unyolo B ali anakoka kuti wamba.

Mwachitsanzo

Malinga ndi kusamutsidwa anakhumba ndi magetsi voteji mawerengedwe imagwiridwa zipembedzo resistors. Mwachitsanzo, ngati m'pofunika kupeza kuchepetsa pa 250 MV ntchito resistors osachiritsika R _T = 120 ohms kuti gwero ali voteji 12 V. Popeza mu nkhani iyi resistors awiri ogwirizana mu kufanana ndi mzake ndi mwamtheradi kuganizira katundu kumbali wolandila, ndi kukondera panopa ndi 0,0042, pamene kulimbikira okwana dera la kukondera ndi 2857 ohms. R _kuona Pankhaniyi adzakhala 1400 ohms, kotero muyenera kusankha chipembedzo yapafupi.

Chitsanzo adzakhala 1.5 kohm resistor ntchito, anaikira kusamutsidwa, komanso ngati resistor kunja kwa volts 12. Komanso, mu yathu dongosolo Mtsogoleri decoupled magetsi linanena bungwe, amene ali membala galimoto mu unyolo gawo.

Kumene, pali zambiri embodiments zina kukondera kuti ntchito RS-485 Converter ndi zinthu zina koma Mulimonsemo, ndikukhazikitsa dongosolo kukondera madera, m'pofunika kuganizira mfundo yakuti malo, amene adzapereka izo, adzakhala nthawi tsekani mwinanso Iwo akhoza kwathunthu kuchotsedwa maukonde.

Ngati pali kuchepetsa, ndiye dera mphamvu A pa osagwira kwathunthu ndi zabwino za dera B, omwe ndi mfundo Buku pamene chipangizo latsopano chikugwirizana ndi mawaya chingwe popanda olemba.

Pachithunzichi Kulumikizana ndi kupotoza

Akuchita ayamikira pamwamba limalola kufala wabwinobwino wa chizindikiro magetsi mu mfundo zosiyanasiyana maukonde, ngati ntchito ngati maziko a RS-485 protocol. Ngati sizinachitike zina zofunika adzauka kupotozedwa. The kuwapotoza kwambiri noticeable kuyamba kuonekera, ngati mlingo deta ndi oposa 1 Mbit / s, koma kwenikweni, ngakhale pa nkhani ya liwiro m'munsi ali osavomerezeka kunyalanyaza malangizo awa, ngakhale maukonde ndi "ntchito zabwino basi."

Momwe pulogalamu?

Pa mapulogalamu, zosiyanasiyana ntchito zimene zimagwira ntchito zipangizo ntchito RS-485 ziboda kapena zipangizo zina ndi mawonekedwe ichi, muyenera kuganizira mfundo zina zofunika. Apa iwo ali:

• Pamaso mudzayamba kutumiza nkhani, muyenera kwenikweni yambitsa ndi chopatsilira. Ngakhale kuti, malinga ndi magwero ena, extradition zingatenge malo yomweyo pambuyo homuweki, akatswiri ena amalangiza chete kwa koyamba, imene nthawi ndi wofanana ndi mlingo wa chimango chimodzi. Pankhaniyi, phwando olondola a nthawi pulogalamu kuzindikira kwathunthu zolakwa chosakhalitsa, ndi kusunga normalization ndondomeko kukonzekera wotsatira phwando deta.
• Pambuyo mamvekedwe otsiriza deta ndi chikalata, izo analimbikitsanso kaye pamaso disconnecting ndi RS-485 chipangizo. Makamaka, ichi ndi chifukwa chakuti akaundula a siriyo doko Mtsogoleri zambiri imodzi pano awiri, woyamba wa limene likufanana ndi polowera ndipo anafuna kulandira deta, pamene lachiwiri kosangalatsa linanena bungwe ntchito ndi linanena bungwe siriyo. usokoneze aliyense kufala Mtsogoleri anapanga pa nkhani ya athandizira m'kaundula chiwonongeko pamene mudziwe kale anapereka kwa kosangalatsa m'kaundula, koma sanabadwe ochokera. Ndi chifukwa chake pambuyo kulengeza ndi linasokonekera, m'pofunika kuti azidya chete ena pamaso disconnecting ndi chopatsilira, amene ayenera kukhala nthawi woposa za 0,5 Akamva kuposa chimango lapansi. Kuchita kuwerengetsera yokwanira bwino analimbikitsa tione mwatsatanetsatane zolembedwa luso ntchito ndi doko siriyo wa Mtsogoleri wa.
• Popeza chopatsilira, wolandila, ndipo mwina, RS-485 Converter chikugwirizana ndi mzere umodzi, mwini wolandirayo mudzazindikira monga kulanda ikuchitika ndi chopatsilira yake. Nthawi zambiri zimachitika kuti mu kachitidwe yodziwika ndi mwayi mwachisawawa kwa mzere, mbali ntchito ndondomeko kuona kuti mwansanga pakati transmitters awiri. M'magulu ochiritsira zikugwira ntchito mogwirizana ndi "mbuye-kapolo", mu ndondomeko kutengerapo bwino kutseka bwinobwino usokoneze ku wolandila lapansi.

Kasinthidwe "basi" mtundu

mawonekedwe Izi amatipatsa kuthekera kwa kaphatikizidwe zipangizo kukula kwa "basi" pamene zipangizo zonse pamodzi kugwiritsa peyala imodzi mawaya. Pankhaniyi, mzere kulankhulana ndi mokakamiza anavomera EOL resistors pa malekezero onse.

Kuonetsetsa harmonization unakhazikitsidwa resistors choncho yodziwika ndi kukana 620 ohms. Iwo nthawizonse anaika pa chipangizo loyamba ndi lomaliza olumikizidwa kwa mzere. zipangizo Advantageously kwambiri masiku ano komanso pano mkati kukana ndi ofananira, amene akhoza optionally muphatikizidwe mu mzere ndi atakhala jumpers pa chida gulu lapadera.

Popeza boma yobereka ndi jumper poyamba anaika, m'pofunika poyamba kuwachotsa ku zipangizo zonse, motero, kupatulapo loyamba ndi lomaliza olumikizidwa kwa mzere. The repeater converters chitsanzo S2000-PI kwa aliyense linanena bungwe ofananira impedance ndi anazimitsa ndi magetsi, pamene zipangizo S2000-wapolisi ndi yodziwika C2000-K Integrated kutsiriziratu impedance, umene mlatho, zofunika kugwirizana wake palibe.

Pofuna wautali mzere kulankhulana, Ndi bwino kugwiritsa ntchito repeaters apadera, transponders, sayenera ndi kulakwa malangizo kwathunthu basi.

Kasinthidwe kwa "nyenyezi" mtundu

nthambi mu RS-485 mizere si zofunika, chifukwa Pankhaniyi pali mokwanira amphamvu chizindikiro kukhota, koma mfundo za maganizo, akhoza kuteteza kukachitika kuti pali kutalika ka nthambi. Pankhaniyi sikutanthauza unsembe wa resistors pa nthambi zosiyana.

The RS-485 yogawa dongosolo, amene ankalamulira ku gulu, ndipo ngati chipangizo chatha olumikizidwa kwa mzere womwewo, koma imayambira zinthu zosiyanasiyana, muyenera kuphatikiza unyolo 0 onse zipangizo ndi kumidzi pofuna mayikidwe a Zoyenereza awo. Ngati chofunika si anakumana, ndiye mphamvu ya kutali atha kugwirizana kusokonekera kwa zipangizo. Ngati chingwe ndi kugwiritsidwa ntchito ndi waya awiriawiri angapo zopotoka, mu nkhani iyi kwa kufanana dera angathe angagwiritsidwe ntchito mfulu kwathunthu awiri ngati kuli kofunika. Mwa zina, komanso amatipatsa kuthekera ntchito isagwe zopotoka awiri kukachitika kuti palibe ndege pansi.

Kodi Ndimaona?

Advantageously kwambiri panopa wakupambana mwa waya equipotential, ndi laling'ono mokwanira, koma mu nkhani 0 V zipangizo kapena okha magwero mphamvu olumikiza busses angapo m'dera grounding kusiyana ulipo pakati pa madera osiyana 0V kungakhale mayunitsi angapo, ndi zina, ngakhale makumi volts, pamene panopa loyenda mwa equalization dera angathe akhoza kukhala yofunika kwambiri. Ichi ndi chifukwa chofala chakuti pali polumikizira kusokonekera pakati pa kutali ndi chipangizo, kuti ngakhale ndithu.

Ndi chifukwa chake inu mukufuna kuti achotse kuthekera pansi dera 0 kapena, pa ambiri, kuuluka unyolo uwu pa ena ina. Muyeneranso kuganiza kuti interconnection pakati pa 0 ndi unyolo zoteteza lapansi pano mu zipangizo ntchito mu dongosolo Ops.

Pa malo, amene yodziwika ndi chilengedwe lolemera ndithu atomu, amatipatsa kuthekera kugwirizana chingwe maukonde mwa "isagwe zopotoka awiri". Pankhaniyi, izo zikhoza kupezeka m'munsi malire osiyanasiyana, kuyambira capacitance a chingwe ndi apamwamba.