LCD WIKI E32R32P, E32N32P 3.2inch IPS ESP32-32E 
Onetsani Buku Logwiritsa Ntchito Module

Buku lothandizira likuwonetsedwa mu chithunzi chotsatirachi:

Chithunzi 1.1 Kalozera wa Paketi Yazidziwitso Zazinthu

Njira zowonetsera ma module a pulogalamuyo ndi izi:

A. Mangani malo opangira mapulogalamu a nsanja ya ESP32;
B. ngati kuli kofunikira, lowetsani malaibulale a mapulogalamu a chipani chachitatu ngati maziko a chitukuko;
C. tsegulani pulojekiti yamapulogalamu kuti iwonongeke, mutha kupanganso pulogalamu yatsopano yamapulogalamu;
D. mphamvu pa gawo lowonetsera, phatikizani ndikutsitsa pulogalamu yochotsa zolakwika, ndiyeno fufuzani momwe pulogalamuyo ikugwirira ntchito;
E. zotsatira za pulogalamuyo sizifika zomwe zikuyembekezeredwa, pitilizani kusintha kachidindo ka pulogalamuyo, kenako phatikizani ndikutsitsa, mpaka zotsatira zake zifike poyembekezeka;

Kuti mumve zambiri zazomwe zapitazi, onani zolembedwa mu 1-Demo directory.

3.1. Pamwambaview Ma module a hardware akuwonetsedwa
Zida za hardware za module zikuwonetsedwa muzithunzi ziwiri zotsatirazi:

Chithunzi 3.1 Module hardware resources 1

Chithunzi 3.2 Module hardware resources 2

Zida za hardware zikufotokozedwa motere:

Kukula kwa chiwonetsero cha LCD ndi mainchesi 3.2, dalaivala IC ndi ST7789, ndipo lingaliro ndi 240 × 320. ESP32 imalumikizidwa pogwiritsa ntchito njira yolumikizirana yamawaya 4 ya SPI.

A. Chiyambi cha ST7789 controller

Wowongolera wa ST7789 amathandizira kusamvana kwakukulu kwa 240*320 ndi GRAM ya 172800-byte. Imathandiziranso ma 8-bit, 9-bit, 16-bit, ndi 18-bit mabasi a data ofanana. Imathandiziranso ma 3-waya ndi ma 4-waya a SPI siriyo madoko. Popeza kuwongolera kofananira kumafuna madoko ambiri a IO, chofala kwambiri ndi SPI serial port control. ST7789 imathandiziranso 65K, 262K RGB mawonetsedwe amtundu, mtundu wowonetsera ndi wolemera kwambiri, pamene ukuthandizira mawonedwe ozungulira ndi mawonedwe a mpukutu ndi kusewerera mavidiyo, kuwonetsera m'njira zosiyanasiyana.

Woyang'anira ST7789 amagwiritsa ntchito 16bit (RGB565) kuwongolera ma pixel, kotero amatha kuwonetsa mpaka mitundu 65K pa pixel iliyonse. Kuyika adilesi ya pixel kumachitika motsatira mizere ndi mizere, ndipo njira yowonjezereka ndi yocheperako imatsimikiziridwa ndi njira yojambulira. Njira yowonetsera ST7789 imachitika pokhazikitsa adilesi ndikuyika mtengo wamtundu.

B. Chiyambi cha SPI communication protocol

Nthawi yolembera ya basi ya 4-waya SPI ikuwonetsedwa pachithunzi chotsatira:

Chithunzi 3.3 Njira yolembera nthawi ya 4-waya SPI basi

CSX ndi kusankha tchipisi cha akapolo, ndipo chip chidzayatsidwa kokha pamene CSX ili pamlingo wochepa mphamvu.
D/CX ndiye pini yowongolera deta / lamulo la chip. Pamene DCX ikulemba malamulo otsika, deta imalembedwa pamtunda wapamwamba
SCL ndi wotchi ya basi ya SPI, yomwe ili ndi mbali zonse zokwera zomwe zimatumiza deta imodzi;
SDA ndi data yofalitsidwa ndi SPI, yomwe imatumiza ma data 8 nthawi imodzi. Mawonekedwe a data akuwonetsedwa pachithunzi chotsatira:

Chithunzi 3.4 4 SPI kufala deta mtundu

Pang'ono pang'ono, perekani poyamba.
Pakulankhulana kwa SPI, data ili ndi nthawi yotumizira, kuphatikiza gawo la wotchi yeniyeni (CPHA) ndi polarity wa wotchi (CPOL):
Mulingo wa CPOL umatsimikizira kuchuluka kwa wotchi yolumikizana, yokhala ndi CPOL=0, kuwonetsa kutsika. CPOL pair transmission protocol
Kukambitsirana kunalibe chikoka chachikulu;

Kutalika kwa CPHA kumatsimikizira ngati wotchi ya synchronous imasonkhanitsa deta pamphepete mwa wotchi yoyamba kapena yachiwiri,
Pamene CPHL=0, sonkhanitsani deta kumapeto kwa kusintha koyamba;
Kuphatikiza kwa mitundu iwiriyi njira zinayi zoyankhulirana za SPI, ndipo SPI0 imagwiritsidwa ntchito kwambiri ku China, komwe CPHL=0 ndi CPOL=0

2) Resistive Kukhudza Screen
Chojambula chogwira ntchito ndi mainchesi 3.2 kukula kwake ndipo chimalumikizidwa ndi XPT2046 control IC kudzera pamapini anayi: XL, XR, YU, YD.

3) ESP32-WROOM-32E gawo
Gawoli lili ndi chipangizo cha ESP32-DOWD-V3 chomangidwa, Xtensa dual-core 32-bit LX6 microprocessor, ndipo imathandizira mawotchi mpaka 240MHz. Ili ndi 448KB ROM, 520KB SRAM, 16KB RTC SRAM, ndi 4MB QSPI Flash. 2.4GHz WIFI, Bluetooth V4.2 ndi Bluetooth Low power modules amathandizidwa. Ma GPIO 26 akunja, kuthandizira khadi ya SD,
UART, SPI, SDIO, I2C, LED PWM, motor PWM, I2S, IR, pulse counter, GPIO, capacitive touch sensor, ADC, DAC, TWAI ndi zina zotumphukira.

4) MicroSD Card Slot
Kugwiritsa ntchito njira yolumikizirana ya SPI ndi kulumikizana kwa ESP32, kuthandizira kwamakhadi a MicroSD amitundu yosiyanasiyana.

5) LED ya RGB yamitundu itatu
Magetsi ofiira, obiriwira ndi abuluu a LED angagwiritsidwe ntchito kusonyeza momwe pulogalamuyo ikugwirira ntchito.

6) Seri Port
Gawo lakunja la doko lakunja limagwiritsidwa ntchito polumikizana ndi serial port.

7) USB kupita ku Seri Port ndikudina Kumodzi Koperani Dera
Chipangizo chachikulu ndi CH340C, mbali imodzi imalumikizidwa ndi kompyuta ya USB, mbali imodzi imalumikizidwa ndi doko la ESP32, kuti mukwaniritse USB kupita kudoko la TTL.
Kuphatikiza apo, kutsitsa kumodzi kumalumikizidwanso, ndiko kuti, mukatsitsa pulogalamuyo, imatha kulowa munjira yotsitsa, popanda kufunikira kukhudza kunja.

8) Battery Interface
Maonekedwe a pini ziwiri, imodzi ya electrode yabwino, imodzi ya electrode negative, pezani mphamvu ya batri ndi kulipiritsa.

9) Battery Charge ndi Discharge Management Circuit
Chipangizo chapakati ndi TP4054, derali limatha kuwongolera batire pakalipano, batire imayimbidwa motetezeka kuti ifike pamalo okhazikika, komanso imatha kuwongolera kutulutsa kwa batri.

10) BOOT Key
Gawo lowonetsera litayatsidwa, kukanikiza kudzatsitsa IO0. Ngati nthawi yomwe gawoli layatsidwa kapena ESP32 yakhazikitsidwa, kutsitsa IO0 kudzalowa munjira yotsitsa. Nkhani zina zitha kugwiritsidwa ntchito ngati mabatani wamba.

11) Chiyankhulo cha Type-C
Chiwonetsero chachikulu chamagetsi ndi mawonekedwe otsitsa pulogalamu ya gawo lowonetsera. Lumikizani USB ku doko la serial ndikudina kamodzi kutsitsa dera, lingagwiritsidwe ntchito popereka mphamvu, kutsitsa ndi kulumikizana kwakanthawi.

12) 5V mpaka 3.3V Voltagndi Regulator Circuit
Chipangizo chachikulu ndi chowongolera cha ME6217C33M5G LDO. VoltagE regulator dera amathandizira 2V ~ 6.5V lonse voltage input, 3.3V khola voltage linanena bungwe, ndipo kutulutsa kwakukulu komweku ndi 800mA, komwe kumatha kukwaniritsa voliyumutage ndi zofunikira zapano za module yowonetsera.

13) Bwezeraninso Chinsinsi
Gawo lowonetsera litayatsidwa, kukanikiza kudzakokera pini yokhazikitsiranso ESP32 pansi (malo osakhazikika amakoka), kuti mukwaniritse ntchito yokonzanso.

14) Resistive Touch Screen Control Circuit
Chipangizo chachikulu ndi XPT2046, chomwe chimalumikizana ndi ESP32 kudzera mu SPI.
Dera ili ndi mlatho pakati pa chotchinga chotchinga chotchinga ndi mbuye wa ESP32, yemwe ali ndi udindo wotumiza zidziwitso pakompyuta kupita kwa mbuye wa ESP32, kuti apeze zolumikizira za malo okhudza.

15) Wonjezerani Pini Yolowetsa
Madoko awiri a IO osagwiritsidwa ntchito pa gawo la ESP32 amapangidwa kuti agwiritsidwe ntchito pozungulira.

16) Backlight Control Circuit
Chipangizo chachikulu ndi BSS138 field effect chubu. Mapeto amodzi a derali amalumikizidwa ndi pini yowongolera kuwala kwa backlight pa ESP32 master, ndipo mbali inayo imalumikizidwa ndi mtengo woyipa wa LCD screen backlight LED l.amp. Pini yowongolera ma backlight imakoka, kuwala kumbuyo, kwina kuzimitsa.

17) Chiyankhulo cha Spika
Mawaya ma terminals ayenera kulumikizidwa molunjika. Amagwiritsidwa ntchito pofikira ma mono speaker ndi zokuzira mawu.

18) Mphamvu Yomvera AmpLifier Circuit
Chipangizo chachikulu ndi mawu a FM8002E ampwopereka IC. Mapeto amodzi a derali amalumikizidwa ndi pini yotulutsa mtengo ya ESP32 audio DAC ndipo mbali inayo imalumikizidwa ndi mawonekedwe a nyanga. Ntchito ya dera ili ndikuyendetsa lipenga lamphamvu laling'ono kapena sipika kuti limveke. Pamagetsi a 5V, mphamvu yayikulu yoyendetsa ndi 1.5W (katundu 8 ohms) kapena 2W (katundu 4 ohms).

19) SPI Peripheral Interface
4-waya yopingasa mawonekedwe. Tulutsani pini yosankha chip yosagwiritsidwa ntchito ndi pini yolumikizira ya SPI yogwiritsidwa ntchito ndi khadi ya MicroSD, yomwe imatha kugwiritsidwa ntchito pazida zakunja za SPI kapena madoko wamba a IO.

20) I2C Peripheral Interface
4-waya yopingasa mawonekedwe. Tulutsani zikhomo ziwiri zosagwiritsidwa ntchito kuti mupange mawonekedwe a I2C, omwe angagwiritsidwe ntchito pazida zakunja za IIC kapena madoko wamba a IO.

Chithunzi cha 3.5 Type-C mawonekedwe ozungulira

Muderali, D1 ndi diode ya Schottky, yomwe imagwiritsidwa ntchito kuletsa zomwe zikuchitika kuti zisinthe. D2 mpaka D4 ndi ma electrostatic surge protection diode kuti ateteze gawo lowonetsera kuti lisawonongeke chifukwa champhamvu kwambiri.tage kapena dera lalifupi. R1 ndiye kukana kutsitsa. USB1 ndi basi ya Type-C. Gawo lowonetsera limalumikizana ndi magetsi a Type-C, mapulogalamu otsitsa, ndi kulumikizana kwa doko kudzera pa USB1. Kumene + 5V ndi GND ali ndi mphamvu zabwino voltage ndi ma siginecha apansi USB_D- ndi USB_D+ ndi ma siginecha osiyanitsira a USB, omwe amatumizidwa kudera la USB kupita ku siriyo.

Chithunzi 3.6 Voltagndi woyang'anira dera

Muderali, C16 ~ C19 ndiye cholumikizira fyuluta, chomwe chimagwiritsidwa ntchito kusungitsa kukhazikika kwa voliyumu yolowera.tage ndi zotuluka voltage. U1 ndi 5V mpaka 3.3V LDO yokhala ndi nambala yachitsanzo ME6217C33M5G. Chifukwa mabwalo ambiri pamagawo owonetsera amafunikira magetsi a 3.3V, ndipo kuyika kwamphamvu kwa mawonekedwe a Type-C kwenikweni ndi 5V, kotero vol.tage regulator kutembenuka dera likufunika.

Chithunzi 3.7 Resistive touch screen control circuit

Muderali, C25 ndi C27 ndi bypass fyuluta capacitors, zomwe zimagwiritsidwa ntchito kusunga voliyumu yolowera.tagndi kukhazikika. R22 ndi R32 ndi zopinga zokokera mmwamba zomwe zimagwiritsidwa ntchito kusunga pini yosasinthika kukhala yokwera. U4 ndi XPT2046 control IC, ntchito ya IC iyi ndikupeza coordinate vol.tage mtengo wa touch point of the resistance touch screen kudzera X+, X-, Y+, Y- four pin, ndiyeno kudzera mu ADC conversion, ADC value is transmitted to ESP32 master. Mbuye wa ESP32 ndiye amasintha mtengo wa ADC kukhala mtengo wogwirizanitsa wa pixel wa chiwonetserocho. XPT2046 imalumikizana ndi mbuye wa ESP32 kudzera pa basi ya SPI, ndipo chifukwa imagawana basi ya SPI ndi chiwonetsero, mawonekedwe ake amayendetsedwa kudzera pa pini ya CS. Pini ya PEN ndi pini yosokoneza, ndipo mulingo wolowetsa umakhala wotsika pakakhudza chochitika.

Chithunzi 3.8 USB kupita ku doko la serial ndikudina kamodzi kutsitsa dera

Muderali, U3 ndi CH340C USB-to-serial IC, yomwe sifunikira oscillator yakunja ya kristalo kuti ithandizire kupanga dera. C6 ndi bypass fyuluta capacitor yomwe imagwiritsidwa ntchito kusunga voliyumu yoloweratagndi kukhazikika. Q1 ndi Q2 ndi ma triodes amtundu wa NPN, ndipo R6 ndi R7 ndi ma triode base ochepetsa zopinga zapano. Ntchito ya derali ndikuzindikira USB kupita ku doko la serial ndikudina kamodzi kutsitsa ntchito. Chizindikiro cha USB ndikulowetsa ndi kutulutsa kudzera mu UD+ ndi UD- mapini, ndipo imatumizidwa kwa mbuye wa ESP32 kudzera pa RXD ndi TXD mapini pambuyo pa kutembenuka. Dinani kamodzi kutsitsa dera:

A. Zikhomo za RST ndi DTR za CH340C zotulutsa mulingo wapamwamba mokhazikika. Panthawiyi, Q1 ndi Q2 triode sizimayatsidwa, ndipo mapini a IO0 ndi mapini okonzanso a ESP32 main control amakokedwa mpaka apamwamba.
B. Mapini a RST ndi DTR a CH340C otsika otsika, panthawiyi, Q1 ndi Q2 triode akadali osayatsidwa, ndipo mapini a IO0 ndi mapini okonzanso a ESP32 akuluakulu amakokedwabe mpaka kufika pamtunda wapamwamba.
C. Pini ya RST ya CH340C imakhalabe yosasinthika, ndipo pini ya DTR imatulutsa mlingo wapamwamba. Panthawiyi, Q1 ikadadulidwa, Q2 ikugwiritsidwa ntchito, pini ya IO0 ya mbuye wa ESP32 imakokedwabe, ndipo pini yobwezeretsanso imatsitsidwa, ndipo ESP32 imalowa m'malo okonzanso.
D. CH340C's RST pin imatulutsa mulingo wapamwamba, pini ya DTR imatulutsa mulingo wochepa, panthawiyi Q1 yayatsidwa, Q2 yazimitsidwa, pini yokhazikitsiranso ya ESP32 main control sikhala yokwera chifukwa cholumikizira cholumikizidwa chikuyimbidwa, ESP32 ndi ikadali mukusinthanso, ndipo pini ya IO0 imatsitsidwa nthawi yomweyo, panthawiyi ilowa mumayendedwe otsitsa.

Chithunzi 3.9 Mphamvu yomvera amplifier circuit

Muderali, R23, C7, C8 ndi C9 amapanga RC fyuluta dera, ndipo R10 ndi R13 ndi mapindu kusintha resistors ntchito. ampmpulumutsi. Pamene mtengo wotsutsa wa R13 sunasinthidwe, mtengo wotsutsa wa R10 wocheperako, wokulirapo wa wokamba nkhani wakunja. C10 ndi C11 ndi ma coupling capacitors olowa. R11 ndiye chokokera mmwamba. JP1 ndiye doko / doko loyankhulira. U5 ndi mphamvu ya audio ya FM8002E ampwopereka IC. Pambuyo polowetsa ndi AUDIO_IN, siginecha ya audio ya DAC imakhala ampzotsimikiziridwa ndi kupindula kwa FM8002E ndi zotulukapo kwa wokamba nkhani/wokamba ndi ma pini a VO1 ndi VO2. SHUTDOWN ndiye pini yothandizira FM8002E. Mulingo wochepa umathandizidwa. Mwachikhazikitso, mlingo wapamwamba umathandizidwa.

Chithunzi 3.10 ESP32-WROOM-32E main control circuit

Muderali, C4 ndi C5 ndi bypass fyuluta capacitor, ndipo U2 ndi ESP32-WROOM-32E modules. Kuti mudziwe zambiri za gawo lamkati la gawoli, chonde onani zolembedwa zovomerezeka.

Chithunzi 3.11 Key reset circuit

Muderali, KEY1 ndiye fungulo, R4 ndiye chokokera mmwamba, ndipo C3 ndiye wochedwa capacitor. Bwezerani mfundo:

A. Pambuyo pa kuyatsa, C3 amalipira. Panthawiyi, C3 ikufanana ndi dera lalifupi, pini ya RESET imakhazikitsidwa, ESP32 ikulowa m'malo okonzanso.
B. Pamene C3 yachajidwa, C3 ikufanana ndi kutsegula dera, pini ya RESET imakokedwa, kubwezeretsanso kwa ESP32 kwatha, ndipo ESP32 imalowa m'malo ogwirira ntchito.
C. Pamene KEY1 ikanikizidwa, pini ya RESET imakhazikika, ESP32 imalowa mu chikhalidwe chokonzanso, ndipo C3 imatulutsidwa kudzera mu KEY1.
D. KEY1 ikatulutsidwa, C3 imaperekedwa. Panthawiyi, C3 ikufanana ndi dera lalifupi, pini ya RESET imakhazikitsidwa, ESP32 ikadali mu RESET state. C3 ikatha, pini yokhazikitsiranso imakokedwa, ESP32 imakhazikitsidwanso ndikulowa m'malo ogwirira ntchito.

Ngati RESET sinapambane, mtengo wololera wa C3 ukhoza kuwonjezeka moyenerera kuti muchedwetse pini yobwezeretsanso nthawi yotsika.

Chithunzi 3.12 Interface circuit ya serial module

Muderali, P2 ndi 4P 1.25mm phula mpando, R29 ndi R30 ndi impedance balance resistors, ndipo Q5 ndi munda zotsatira chubu kulamulira 5V athandizira magetsi. R31 ndi chopinga chotsitsa. Lumikizani RXD0 ndi TXD0 ku ma serial pin, ndikupereka mphamvu kumapini ena awiriwo. Doko ili ndi lolumikizidwa ku doko lofanana ndi doko la USB-to-serial port module.

Chithunzi 3.13 Zowonjezera za IO ndi zozungulira zozungulira

Muderali, P3 ndi P4 ndi mipando 4P 1.25mm, ndipo JP3 ndi 2P 1.25mm mipando phula. R33 ndi R34 ndi I2C pin pull-up resistors. SPI_CLK, SPI_MISO, SPI_MOSI mapini amagawidwa ndi mapini a SPI khadi ya MicroSD. Mapini SPI_CS, IIC_SCL, IIC_SDA, IO35, IO39 sagwiritsidwa ntchito ndi zida zapa board, chifukwa chake amatsogozedwa kuti alumikizane ndi zida za SPI ndi IIC, komanso zitha kugwiritsidwa ntchito pa IO wamba. Zomwe muyenera kuyang'anira:

A. IO35 ndi IO39 zitha kukhala mapini olowetsa okha;
B. Pini ya IIC ikagwiritsidwa ntchito pa IO wamba, ndikwabwino kuchotsa kukana kukoka kwa R33 ndi R34;

Chithunzi 3.13 Battery charge and discharge management circuit

Mu dera ili, C20, C21, C22 ndi C23 ndi bypass fyuluta capacitors. U6 ndiye kasamalidwe ka batire la TP4054 IC. R27 imayang'anira kuchuluka kwa batire. JP2 ndi mpando wa 2P 1.25mm, wolumikizidwa ndi batri. Q3 ndi P-channel FET. R28 ndi Q3 grid kukokera pansi resistor. TP4054 imayitanitsa batire kudzera pa pini ya BAT, yocheperako kukana kwa R27, kukulira kwacharge, kuchuluka kwake ndi 500mA. Q3 ndi R28 palimodzi amapanga gawo lotulutsa batire, pomwe palibe magetsi kudzera pa mawonekedwe a Type-C, + 5V vol.tage ndi 0, ndiye chipata cha Q3 chimatsitsidwa mpaka pansi, kukhetsa ndi gwero zili, ndipo batri imapereka mphamvu ku gawo lonse lowonetsera. Ikayendetsedwa ndi mawonekedwe a Type-C, + 5V voltage ndi 5V, ndiye chipata cha Q3 ndi 5V pamwamba, kukhetsa ndi gwero zimadulidwa, ndipo batire imasokonekera.

Chithunzi 3.14 18P LCD gulu ma waya kuwotcherera mawonekedwe

Muderali, C24 ndiye bypass fyuluta capacitor, ndipo QD1 ndi 18P 0.8mm phula madzi crystal chophimba kuwotcherera mawonekedwe. QD1 ili ndi pini ya siginecha yotsutsa, LCD screen voltagpini ya e, pini yolumikizirana ya SPI, pini yowongolera ndi pini yoyendera ma backlight. ESP32 imagwiritsa ntchito zikhomozi kuwongolera LCD ndi touch screen.

Chithunzi 3.15 Tsitsani batani lozungulira

Muderali, KEY2 ndiye fungulo ndipo R5 ndiye chokokera mmwamba. IO0 ndi yokwera mwachisawawa komanso yotsika pamene KEY2 ikanikizidwa. Dinani ndikugwira KEY2, yambitsani kapena yambitsaninso, ndipo ESP32 idzalowetsamo kutsitsa. Nthawi zina, KEY2 itha kugwiritsidwa ntchito ngati kiyi wamba.

Chithunzi 3.15 Kuzindikira mulingo wa batri

Muderali, R2 ndi R3 ndi gawo la voltage resistors, ndi C1 ndi C2 ndi bypass fyuluta capacitors. Mphamvu ya batri voltagKulowetsa kwa ma sign a BAT + kumadutsa pagawo logawanitsa. BAT_ADC ndiye voltage mtengo pamapeto onse a R3, omwe amaperekedwa kwa mbuye wa ESP32 kudzera pa pini yolowera, kenako amasinthidwa ndi ADC kuti pamapeto pake apeze mphamvu ya batri.tagndi mtengo. Voltage divider imagwiritsidwa ntchito chifukwa ESP32 ADC imatembenuza kuchuluka kwa 3.3V, pomwe batire yodzaza mphamvu.tage ndi 4.2V, yomwe ili kunja kwake. Voltage kuchulukitsidwa ndi 2 ndiye batire yeniyeni voltage.

Chithunzi 3.16 LCD backlight control circuit

Muderali, R24 ndiye kukana kosokoneza ndipo imasungidwa kwakanthawi. Q4 ndi N-channel field effect chubu, R25 ndiye Q4 grid pull-down resistor, ndipo R26 ndiye backlight current limiting resistor. LCD backlight LED Lamp ili mu chikhalidwe chofanana, mtengo wabwino umagwirizanitsidwa ndi 3.3V, ndipo mtengo woipa umagwirizanitsidwa ndi kukhetsa kwa Q4. Pamene pini yowongolera LCD_BL imatulutsa mphamvu zambiritage, kukhetsa ndi gwero la Q4 zimayatsidwa. Panthawiyi, mzati woipa wa LCD backlight wakhazikika, ndi kuwala kwa LED Lamp imayatsidwa ndikutulutsa kuwala. Pamene pini yowongolera LCD_BL imatulutsa mphamvu yotsikatage, kukhetsa ndi gwero la Q4 zadulidwa, ndipo kuwala koyipa kwa chophimba cha LCD kuyimitsidwa, ndi kuwala kwa LED l.amp sichiyatsidwa. Mwachikhazikitso, LCD backlight yazimitsidwa. Kuchepetsa kukana kwa R26 kumatha kukulitsa kuwala kowala kwa backlight. Kuphatikiza apo, pini ya LCD_BL imatha kulowetsa chizindikiro cha PWM kuti isinthe kuwala kwa LCD.

Chithunzi 3.17 LCD backlight control circuit

Muderali, LED2 ndi RGB yamitundu itatu lamp, ndipo R14~R16 ndi l wamitundu itatuamp panopa kuchepetsa resistor. LED2 ili ndi nyali zofiira, zobiriwira ndi zabuluu za LED, zomwe ndizofala kugwirizanitsa anode, IO16, IO17 ndi IO22 ndi zikhomo zitatu zowongolera, zomwe zimayatsa nyali za LED pamlingo wochepa ndikuzimitsa nyali za LED pamtunda wapamwamba.

Chithunzi 3.18 MicroSD khadi slot mawonekedwe dera

Muderali, SD_CARD1 ndi MicroSD khadi slot. R17 mpaka R21 ndi zokokera mmwamba pa pini iliyonse. C26 ndiye bypass fyuluta capacitor. Dera lolumikizirali limatengera njira yolumikizirana ya SPI. Imathandizira kusungirako mwachangu kwamakhadi a MicroSD.
Dziwani kuti mawonekedwewa amagawana basi ya SPI ndi mawonekedwe a SPI otumphukira.