1. RS232: Qhov siab tshaj plaws kis tau tus mob yog li 15 meters, thiab qhov siab tshaj plaws yog 20kb / s. RS -232 yog tsim los rau taw tes rau-taw tes (uas yog, tsuas yog ib khub ntawm kev txais thiab xa khoom) kev sib txuas lus, thiab nws cov neeg tsav tsheb thauj khoom yog 3 ~ 7kΩ. Yog li RS-232 yog qhov tsim nyog rau kev sib txuas lus ntawm cov khoom siv hauv zos.
2.RS485 / RS422: Txhawm rau txhim kho qhov tsis txaus ntawm RS232 kev sib txuas lus nyob deb thiab tus nqi qis, RS422 nce tus nqi xa mus rau 10Mb / s, thiab kev sib kis tau ntev mus txog 4000 ko taw (thaum tus nqi qis dua 100kb / s). Qhov siab tshaj plaws kis tau tus mob yog 1219 meters, thiab qhov siab tshaj plaws kis tau tus mob yog 10Mb / s.
3.RS485: Tus qauv RS-485 yog tsim los ntawm RS-422, ntxiv cov peev xwm sib txuas lus ntau thiab ob txoj kev.
4.Serial chaw nres nkoj thiab COM chaw nres nkoj xa mus rau lub cev interface daim ntawv (hardware). TTL, RS-232, thiab RS-485 xa mus rau theem tus qauv (hluav taws xob teeb liab) ntawm qhov chaw nres nkoj serial.
5.Thaum xaim, feem ntau tsuas yog txuas GND, RX (receive), thiab TX (transmit). Tsis txhob txuas cov kab hluav taws xob xws li Vcc kom tsis txhob muaj teeb meem nrog cov khoom siv hluav taws xob ntawm lub hom phiaj ntaus ntawv. (Txoj cai tswjfwm: TX ntawm tus tswv tsev txuas nrog RX ntawm lub hom phiaj ntaus ntawv, thiab RX ntawm tus tswv yog txuas nrog TX ntawm lub hom phiaj ntaus ntawv, tab sis ntau tus neeg tsim qauv txhob txwm thim rov qab cov cim ntawm RX thiab TX txhawm rau ua kom cov xov hlau intuitive ntau dua, koj tuaj yeem sim pauv tom qab txuas tus 200-1kΩ resistor. Los yog No.4 txoj kev.)
6.Serial kev sib txuas lus feem ntau tsis muaj kev tuav tes raws tu qauv, yog li koj tuaj yeem txuas GND thiab RX nkaus xwb rau kev txais tos dawb huv, lossis tsuas yog GND thiab TX rau kev sib kis dawb huv.
7.Qhov yuam kev ntawm qhov chaw nres nkoj thaiv yuav hlawv cov nti, piv txwv li: 1 rub siab los ntawm ib qho TX yog nchuav rau hauv 0 rub qis los ntawm lwm TX.(Thaum koj tsis paub meej txog lub ntsiab lus ntawm lub hom phiaj thaiv, koj tuaj yeem sim txhawm rau txuas TX thiab RX ntawm lwm lub cuab yeej nrog txoj kab txiav txim siab ua RX kom pom tias cov ntaub ntawv tau txais.)
8. CH340, PL2303, CP2102, FT232R chips are USB-to-serial (TTL level output) chips, and Windows drivers need to be installed. (Commonly used to add serial ports in notebooks, note that its compatibility is not as good as the onboard serial ports. Preferred choice: FT232R > CP2102 >ZPO 2303)
9.MAX232 yog bidirectional conversion nti ntawm TTL qib thiab RS232 qib. Cov pins sib txawv paub txog kev ua haujlwm ntawm TTL rau RS -232 lossis RS -232 rau TTL. (Muaj ntau TTL thiab RS232 hloov dua siab tshiab chips, thiab tus naj npawb ntawm pem hauv ntej thiab rov qab interfaces txawv: piv txwv li: MAX202, SP213, MAX3232)
10.TTL qib tus qauv yog qib qis yog {{0}}, qib siab yog 1 (rau GND kab voltage, tus qauv digital circuit logic). Tus qauv RS -232 qib yog qhov zoo theem yog 0, thiab qhov tsis zoo yog 1 (tsis yog rhiab heev rau qib GND kab thiab tus nqi tshwj xeeb ntawm qhov voltage).
11.RS-485, RS-422 zoo ib yam li RS-232, tab sis siv cov teeb liab sib txawv, uas tsim nyog rau kev cuam tshuam kev cuam tshuam / kev sib kis ceev. Hla nws ntawm no.
12. D-hom 9-pin plug (onboard serial chaw nres nkoj, txiv neej chaw nres nkoj) qab lub desktop computer yog RS-232 qib. Yuav hloov mus rau TTL qib los ntawm MAX232.
Koj tuaj yeem yuav peb cov khoom siv cable serial los ntawm kev txuas hauv qab no:
https://www.pcm-cable.com/serial-cable/
