BÁO CÁO_PIC16F877A_LM35_LCD

8/3/2019 BO CO_PIC16F877A_LM35_LCD

1/20

BO CO N THIT K K THUTCN BN V PIC16F877A

O NHIT DNG LM35, HIN TH LN LCD

Sau y l qui trnh tm hiu v PIC ca nhm

1. Trc ht nhm ln mng tm hiu tng quan v PIC xem mnh nn bt u t u, v ch yu hc t din nwww.picvietnam.com, tin th nhm xin gi li cm n ti din n ny.

Nhm tm c 1 bi dn dt v PIC ca tc gi FALLEAF, v theo th hcPIC ta nn bt u bng vic tm hiu v cc khi nim v lm cc cng vic

-Thanh ghi-register

-C-flag

-nh thi-Timer

-Lm mch nhp nhy Led

Nhng nu search trn mng vi t kho PIC v cc khi nim ny th c rt t, thm chnhm tm khng ra. L do n gin v cc phn kin thc ny ng l phi c hc trong ccmn tin cho PIC nh kin trc my tnh hay vi x l.

Nhm tm ti hi cc anh i trc, v theo hng dn ca anh Ca ( SV Bch Khoa K05)th nn tm hiu v vi iu khin 8051 trc, v nn hc lp trnh bng ASM

tm hiu 8051, nhm tm c sch v 8051 ca tc gi Tng Vn On. Chnh trongsch ny, nhm hiu c cc khi nim v thanh ghi, nh thi, v ngn ng ASM (ch mc cn bn)

Nhm xin c ni v cch hiu ca mnh v cc khi nim trn

Thanh ghi

Trong mt vi x l 8051 c rt nhiu thanh ghi (khong hn trm thanh) mithanh l mt chui cc bit, mi bit c 2 gi tr l 1 hoc 0 v c th uc gn bi ngi lp trnh,a s thanh ghi c 8 bit, ngoi ra cn c cc thanh 13 bit. Mi thanh nh th c cc chc nngring.
http://www.picvietnam.com/http://www.picvietnam.com/


2/20

C thanh ch n thun ch nh mt gi tr no , thanh ghi 8 bit th ch nh

c 82 256= gi tr t 0 ti 255

C thanh dng iu khin, v d thanh ghi cho php xut hoc nhp PORTB.PORTB c 8 chn, mi chn c iu khin l chn xut hay nhp bi thanh ghi PORTB. Nu

thanh ghi PORTB c gi tr 00000001b th c ngha l chn B0 l chn nhp d liu, cn ccchn B1-B7 l chn xut d liu

C (flag)

C cng l 1bit, nhng n c chc nng c bit hn cc bit khc nn ngi ta ttn cho n. Ta s hiu k hn v n qua mt v d trong phn timer

nh thi (Timer)

nh thi l mt chc nng khng th thiu ca cc vi iu khin, n cho php viiu khin m thi gian. Tuy nhin khng th m mt cch trc tip nh con ngi c,timer m thi gian thng qua vic m xung dao ng. Mt vi iu khin c khong vi timer.

B nh thi cng l cc thanh ghi, chng c iu khin bi bit nh thi. Khita set bit nh thi bng 1 th thanh ghi nh thi bt u nhy s 0, 1, 10 cho n khi thanhghi nh thi c gi tr 11111111. Bit 7 ca thanh ghi nh thi l mt c, bnh thng th bit nybng 0, cho n khi thanh ghi m ln ti gi tr max th bit ny mi bng 1, v sau thanh

ghi timer li tr v gi tr 0 v bt u m li, , v n ch dng khi bit nh thi c gn bng 0tr li. C ny nh mt cch nh du mt chu k m, gia 2 ln c ny bng 1 l 256 gi tr c m

Cng c timer nhiu hn 8bit

Hp ng ASM

Vi iu khin mun hot ng c phi c cc ch dn cho n lm vic, lcc file hex. M mt file hex ta thy ton nhng 0 vi 1. Con ngi s mt rt nhiu thi gian vit nn 1 chng trnh ton 0 vi 1, v vy ngi ta xy dng cc ngn ng lp trnh. Thay vvit 1 dng lnh ton 0 vi 1 th ta vit mt dng lnh khc tng ng nhng gn gi hn vingn ng con ngi. Ngn ng cng gn vi con ngi th c cp cng cao.

ASM l ngn ng gn vi file hex nht. Lm vic vi ASM ta ch yu lm vicvi cc bit, nh vic set bit bng 1 hay di chuyn gi tr t thanh ghi ny sang thanh ghi khc,


3/20

2. Sau khi tm hiu qua sch v nhng khi nim ny txong, nhm bt u chnh thc tm hiu v PIC.

Cng c m phng hu hiu l ProteusNgn ng lp trnh l CCS, hc t Tutorial ca anh Trn Xun Trng K2001 HBKNhm tm hiu v PIC thng qua tutorial ca tc gi Nguyn Trung Chnh trn din n

picvietnam, xin cm n anh Chnh vit mt tutorial rt hay v cn bn v xin php ly cchnh nh minh ho t tutorial ny

S chn ca PIC16F877A :


4/20

PIC hot ng ta cn cp ngun cho PIC. Ngoi ra c th thm vo b dao ng thch

anh, v nt nhn reset:


5/20

V y l mch nhy Led PortB:


6/20

M phng bng Proteus:

- Mch nhp nhy Led

PIC16F877A

Led

Tr 330 Ohm

Dng 1 DCVolmeter chn B0, ta thy in p xut ra chn ny thay i 0V, 5V saumi thi gian delay

Code :

#include#device* =16 ADC=8#FUSESNOWDT,HS,NOPUT,NOPROTECT,NODEBUG,NOBROWNOUT,NOLVP,NOCPD,NOWRT

#use delay (clock=20000000)

void main()


7/20

{

//Thiet lap che do cho PORT B

Set_tris_b(0x00); //Tat ca PORT B deu la cong xuat du lieu

output_b(0xFF); //Mo het cac Led

While(TRUE) //Vong lap vo han

{

output_b(0xFF); //Cho cc Led sng

delay_ms(500); // Delay 0.5s

output_b(0x00); //Tat het cac Led

delay_ms(500); Cho 0.5s

}

}

Sau tin hnh thc nghim:

Phi lm ngun 5V cho PIC

Phi lm mch nhp nhy Led

Sau khi xem qua cc linh kin ca mt anh K05 (anh Ca) bit mt cc linh kin n ralm sao th ra Nht To mua

- Cc dng c c bn;Test board

Board c lM hn, ch, nha thngMi khoan

Ht ch


8/20

- Cc linh kin cho ngun 5V:

Board c l

Bin p cch ly-cn gi l tng ph

7805- dng xn 5V (7806 th xn 6V), c thm nhm tn nhit

Domino

Cu diod

T 1000 uF 35V

T 10uF 50V5

T ko 104

S mch ngun 5V

3. S dng LCD TC1602A

y l LCD 2 hng, mi hang 16 k t

s dng LCD , ta hy c file LCD.C trong th vin Driver ca CCS. CCS

hng dn cch ta i dy cho cc chn ca LCD, ng thi CCS vit sn cho ta cchm thao tc cho LCD:

Cch ni dy:

// As defined in the following structure the pin connection is as follows:


9/20

// D0 enable

// D1 rs

// D2 rw

// D4 D4

// D5 D5

// D6 D6

// D7 D7

// LCD pins D0-D3 are not used and PIC D3 is not used.

Cc hm thng dng

lcd_init() : l hm phi c bo rng s s dng LCD

lcd_putc( char c) : hm xut k t ra LCD

lcd_gotoxy( BYTE x, BYTE y) : hm cho php con tr nhy ti v tr (x,y) trn LCD

M phng v d dng LCD bng Proteus:

Code :

#define

#include "16F877A.h"

#device *=16 adc=8

//#device PIC16F877A *=16

#use delay(clock=20000000)

#FUSES NOWDT, HS, NOPUT, NOPROTECT, NODEBUG, NOBROWNOUT,NOLVP, NOCPD, NOWRT

#use rs232(baud=115200,parity=N,xmit=PIN_C6,rcv=PIN_C7,bits=9)


10/20

#include

void main ()

{

lcd_init();

lcd_putc("Do an ky thuat");

}

Kt qu:


11/20

4. LM35

y l cm bin nhit

LM35 c 3 chn : 2 chn cp ngun v 1 chn xut in p ra ty theo nhit

Nhit tng 1C th in p xut ra chn out ca LM35 tng 10mV

Cc c tnh k thut khc :


12/20

M phng bng Proteus:


13/20

Nhit l 27C, in p xut ra l V=0.27176 chng t s tng 10mV /C l khchnh xc.

Khi m phng Proteus, nu khi LM35 khng hot ng, th click chut phi/ editproperties/ b check exclude from Simulation i.

5. Chc nng ADC ca PIC16F877A

Chc nng ADC cho php PIC nhn tn hiu tng t t cc chn c h tr ADC v chuyn tn hiu sang tn hiu s x l.

Cc chn c h tr ADC ca PIC16F877A l : A0 A1 A2 A3 A5 E0 E1 E2.Mt s lnh cn bn khi dng ADC:

Mun dng ADC, ta phi khai bo #DEVICE cho bit dng ADC my bit, chng hn#device*=16 ADC=8 cho bit dng ADC 8 bit

Setup_ADC(mode)


14/20

.Mode l ADC_OFF : tt chc nng ADC

.Mode l ADC_CLOCK_INTERNAL : thi gian ly mu bng xung clock

.Mode l ADC_CLOCK_DIV_2 : gian ly mu bng xung clock /2

Setup_ADC_ports(value) //Xc nh chn ly tn hiu Analog v in th chun

.Value l ALL_ANALOGS : dng tt c cc chn c h tr ADC

.Value l NO_ANALOG : khng dng ADC

.Value la ANi : dng chn ANi l chn ADC

Set_ADC_channel(channel) //chn chn c gi tr analog bng lnh read_adc()

.Vi PIC16F877A channel c 8 gi tr 0-7 tng ng l cc chn A0-E2 nh k trn

. chnh xc ta nn delay khong 10ms truc khi c tn hiu:

.Vd: set_ADC_channel(0);

delay_ms(10);

read = read_adc();

Sau on code ny, read s c gi tr bng gi tr in p m chn c


15/20

6. Ti y ta cng c lm mch hon chnh

M phng bng Proteus:

Kt qu :


16/20

Code:

#define

#include "16F877A.h"

#device *=16 adc=8

//#device PIC16F877A *=16

#use delay(clock=12000000)

#FUSES NOWDT, HS, NOPUT, NOPROTECT, NODEBUG, NOBROWNOUT,NOLVP, NOCPD, NOWRT

//#use rs232(baud=115200,parity=N,xmit=PIN_C6,rcv=PIN_C7,bits=9)


17/20

#include

#INT_EXT

int8 read;

void main(void)

{

// set_tris_b(0);

set_tris_a(0xFF);

set_tris_d(0x00);

// Khoi tao cho ngat ngoai

enable_interrupts (INT_EXT);

ext_int_edge(H_TO_L);

enable_interrupts (GLOBAL);

//Khoi tao ADC

setup_adc_ports(AN0);

setup_adc(ADC_CLOCK_INTERNAL);

delay_ms(50);

while(TRUE)

{

lcd_init();

read=read_adc();

read =read*1.960784314;


18/20

printf(lcd_putc,"\rNhiet do: %u",read);

delay_us(20);

}

}

Khi dng ADC 8bit, tn hiu ADC c c t chn ADC nh sau:

1V 2V 3V 4V 5V51 102 153 204 255

Tc l nu in p vo 1V th tn hiu digital tng 51

1V ADC=51

1C10mVADC=10*51/1000

Suy ra TADC = T*10*51/1000

Suy ra T = ADC*1000/10/51 = ADC * 1.960784314

Cng thc ny dng on code trn

7. Lm mch thc t:

V mch in dng chc nng ARES trong Proteus:

Xin cm n bn Thi Thin hng dn ti cch s dng ARES

Sau khi v xong s nguyn l nh trn, ta chn nt ARES chuyn qua mch vmch in, sau khi sp xp, b sung, i dy mch v in ra PDF (dng chng trnh inmy in o Virtual PDF Printer ta c c mt s nh sau:


19/20

C th xem ch 3D :


20/20

em mch in trn ra tim in Laser (in phun khng c), ch cc xem bn in cva vi chn PIC khng, nu khng th phi in li vi t l thch hp. Thng thngin ln giy king, nhng in ln giy A4 thng cng c

Mua board ng v t bn in ln, dng bn i i qua li khong 5ph, lc u cngh i lu s n mc, nhng khng phi vy. i board ng ngui ri g ra, nudng giy A4 thng th nn thm thm t nc mc d bm vo ng

Mua thm cy vit v mch in, nu mc ch no cha bm tt th ln.

em board ng ngm vo dung dch FeCl3 mua ch, vt ln xem nu ng btri ht th ly ra, nu cha th ngm tip.

Dng xng chi i lp mc cn bm, ta c c mt mch hon chnh

V cui cng nhm xin cm n nhng ngi ch dn cho chng ti

BÁO CÁO_PIC16F877A_LM35_LCD

Documents

Transcript of BÁO CÁO_PIC16F877A_LM35_LCD