Txoj kev tsav tsheb ntu LED (cov raj digital) nrog IO chaw nres nkoj yog qhov tseeb rau txhua tus neeg, tab sis txoj kev tsav tsheb ncaj qha ntu LCD nrog IO chaw nres nkoj yog qhov nyuaj dua. Kuv tshawb hauv Is Taws Nem rau txoj hauv kev ntawm kev tsav tsheb ntu LCD nrog IO chaw nres nkoj ntawm ib qho-chip microcomputer. Feem ntau ntawm cov ntaub ntawv tsis meej txaus thiab tshwj xeeb, thiab cov teeb meem yooj yim yog qhov nyuaj. Tam sim no, raws li lub hauv paus ntsiab lus ntawm LCD zaub, ua ke nrog cov ntaub ntawv tseem ceeb hauv Is Taws Nem, Kuv yuav qhia luv luv yuav ua li cas siv lub microcomputer ib leeg los tsav cov ntu code LCD kua siv lead ua zaub:
1. Lub hauv paus ntsiab lus ntawm LCD thiab LED yog txawv: LED emits lub teeb nrog qhov zoo voltage, thaum LCD yuav tsum alternated ntxiv qhov zoo thiab rov qab voltage kom tso saib tsis tu ncua (koj tuaj yeem ua ib qho kev sim, yog tias qhov hluav taws xob tas li yog siv rau ib ntu ntawm LCD. , Cov ntu no yuav tshwm sim, tab sis nws yuav tsis tshwm sim tam sim ntawd, thiab qhov hluav taws xob tas li yuav siv tau rau lub sijhawm ntev, uas yuav ua rau kom muaj kev laus thiab kev puas tsuaj ntawm LCD)
2. Kuv tau hnov dab tsi txog 1/2bias thiab 1/3bias LCD? Rau 1/2bias LCD, yog hais tias cov zaub voltage ntawm lub LCD yog 3V, ces 1/2bias yog 1.5V, uas yog hais tias, thaum lub voltage ntawm ± 3V yog thov, lub LCD yuav tso saib; Thaum qhov hluav taws xob ntawm ± 1.5V thiab hauv qab no yog siv, tsis muaj zaub.
3. Qhov chaw nres nkoj IO ntawm ib leeg-chip microcomputer tsis tuaj yeem ncaj qha tso tawm ib nrab-siab theem (1.5V), tab sis nws tuaj yeem pom tau tias muaj kev sib npaug ntawm rub-up thiab rub-down resistors. Thaum qhov chaw nres nkoj IO tau teeb tsa raws li cov tswv yim (siab tsis kam), vim yog ib feem ntawm kev rub-up thiab rub-down resistors, Tsim ib nrab-siab (1.5V)
Tom qab paub txog 3 lub ntsiab lus saum toj no, nws tsis yooj yim rau tsav LCD dynamically. Rau 4 * 8 ntu LCD (4 COM, 8 SEG, tso saib voltage 3V, 1/2 bias), txoj kev tsav tsheb yog raws li hauv qab no:
1. Plaub lub COMs raug tshuaj xyuas ua ke, thiab txhua lub COM ua ib qho kev hloov hluav taws xob thaum lub sij hawm ob qho tib si scans.
2. Yog hais tias ib qho COM scanned, COM yuav tso zis 3V (0V):
SEG cov zis txuas nrog qhov no COM yog rov qab rau COM, ΔV=± 3V, ces qhov kev sib txuas no yuav teeb;
SEG cov zis txuas nrog COM no yog tib yam li COM, ΔV=0, ces qhov txuas txuas tsis kaj.
3. Rau lwm cov COMs uas tsis tau luam theej duab, IO chaw nres nkoj ntawm ib leeg-chip microcomputer yog input, uas generates 1/2 bias (1.5V). Txawm hais tias tus nqi ntawm SEG, ΔV<±1.5v, so="" the="" light="" does="" not="" light="">
