RS-232 thiab RS-422 yog ob qho tib si cov qauv kev sib txuas lus, tab sis lawv muaj cov yam ntxwv hluav taws xob sib txawv thiab cov theem teeb liab. Txawm hais tias nws tuaj yeem siv RS-232 cable rau RS-422 kev sib txuas lus hauv qee kis, nws tsis pom zoo thiab yuav tsis ua haujlwm tau zoo hauv txhua qhov xwm txheej. Nov yog cov lus piav qhia ntxaws txog qhov sib txawv tseem ceeb ntawm RS-232 thiab RS-422 thiab yog vim li cas siv RS-232 cable rau RS-422 tsis zoo tagnrho.
Cov yam ntxwv hluav taws xob:
RS {{0}} yog tus qauv nkaus xwb, uas txhais tau hais tias nws siv qhov ntsuas hluav taws xob txheeb ze rau hauv av rau kev taw qhia. Nws feem ntau ua haujlwm ntawm qib voltage ntawm -15V rau ntxiv rau 15V, nrog cov voltages tsis zoo sawv cev rau logic 1 thiab qhov zoo voltages sawv cev logic 0.
RS {{0}}, ntawm qhov tod tes, yog tus qauv sib txawv, txhais tau tias nws siv ob lub xov hlau xa cov ntaub ntawv sib txawv. Nws ua haujlwm ntawm qib qis dua RS-232, feem ntau ntawm -6V rau ntxiv 6V. Hauv RS-422, qhov sib txawv ntawm qhov sib txawv ntawm ob lub xov hlau sawv cev rau logic 1, thaum qhov sib txawv ntawm qhov hluav taws xob sib txawv sawv cev rau lub logic 0.
Cov theem teeb liab:
RS-232 siv ib txoj kev taw qhia ib leeg, uas ua rau nws raug rau lub suab nrov thiab cuam tshuam. Nws yog tsim los rau luv luv, feem ntau mus txog 15 meters (50 ko taw) yam tsis siv cov khoom siv ntxiv.
RS-422, ua tus qauv sib txawv, muab kev tiv thaiv suab nrov zoo dua thiab tuaj yeem txhawb nqa ntev dua cable. Nws yog tsim los rau kev ncua mus txog 1200 meters (4000 ko taw) los yog ntev dua nrog cov repeaters lossis extenders.
Kev Siv Cable:
RS-232 cables feem ntau siv ib tug 9-pin los yog 25-pin connector, nrog rau cov pin sib txawv nyob ntawm tus ntaus ntawv. Cov kab hluav taws xob muaj ntau cov kab teeb liab, suav nrog cov ntaub ntawv xa tawm (TX), txais cov ntaub ntawv (RX), hauv av (GND), thiab tswj cov teeb liab xws li Thov xa (RTS) thiab Clear To Send (CTS).
RS-422 cables kuj siv cov khoom sib txuas zoo sib xws tab sis muaj qhov sib txawv ntawm tus pin. Lawv xav tau ob txoj hlua sib tw ntawm cov xov hlau sib txawv, feem ntau hu ua "A" thiab "B" khub. Tsis tas li ntawd, RS-422 suav nrog cov teeb liab sib txawv ntawm cov ntaub ntawv xa tawm (TX ntxiv thiab TX-), qhov sib txawv tau txais cov ntaub ntawv (RX ntxiv thiab RX-), thiab hauv av (GND).
Qhov sib txawv ntawm impedance:
RS-422 yuav tsum tau txiav kom raug thiab impedance txuam kom ntseeg tau tias cov ntaub ntawv xa mus. Tus qauv impedance rau RS-422 yog 100 ohms, thiab cov kab hluav taws xob thiab kev txiav tawm yuav tsum phim qhov impedance no kom tsis txhob cuam tshuam cov teeb liab thiab cov ntaub ntawv yuam kev.
RS -232 cables, ntawm qhov tod tes, feem ntau tsis muaj impedance txuam cov cai, vim lawv tsis yog tsim los rau kev sib txuas lus ntev lossis kev sib txuas lus siab.
Xav txog qhov sib txawv no, siv RS-232 cable rau RS-422 kev sib txuas lus tsis pom zoo rau cov laj thawj hauv qab no:
Voltage Levels: RS-232 siv voltage ntau dua RS-422. Kev sib txuas ntawm RS-232 cable rau RS-422 interface tuaj yeem ua rau cov qib tsis raug, uas ua rau cov khoom siv RS-422 puas.
Txoj Kev Teeb Meem: RS-232 siv lub teeb liab ib leeg, thaum RS-422 siv cov teeb liab sib txawv. Cov yam ntxwv hluav taws xob thiab kev tiv thaiv suab nrov ntawm RS-422 yog tsim tshwj xeeb rau kev sib txuas lus nyob deb. Ib qho RS-232 cable yuav tsis muab lub suab nrov tiv thaiv, ua rau cov ntaub ntawv yuam kev lossis kev sib txuas lus tsis txaus ntseeg.
Kev Siv Hluav Taws Xob thiab Pin: RS-232 thiab RS-422 cables muaj qhov sib txawv ntawm tus pin thiab teeb liab teeb tsa. Txuas lub RS-232 cable mus rau RS-422 interface yuav tsis sib xws rau cov xov hlau uas yuav tsum tau ua, ua rau cov teeb liab tsis raug thiab kev sib txuas lus tsis raug.
Impedance Matching: RS-422 yuav tsum muaj kev sib piv impedance, uas tsis muaj nyob hauv RS-232 cables. Kev tsis sib haum xeeb impedance tuaj yeem ua rau cov teeb liab cuam tshuam, txo qhov zoo thiab kev ntseeg siab ntawm cov ntaub ntawv xa mus.
Hauv kev xaus, thaum nws tuaj yeem ua rau lub cev txuas RS -232 cable rau RS-422 interface, nws tsis pom zoo vim tias qhov sib txawv tseem ceeb hauv qib voltage, kev taw qhia, kev xaim, thiab impedance. . Txhawm rau kom ntseeg tau tias kev sib txuas lus zoo thiab tsim nyog, nws yog qhov zoo tshaj plaws los siv cables thiab interfaces tshwj xeeb tsim rau RS-422 thaum ua haujlwm nrog RS-422 cov khoom siv.
