BÀI 26 : ĐO NHIỆT ĐỘ LM335 HIỂN THỊ LCD PIC16F887 XC8

Xem lý thuyết về LM335 bên PIC16F877A nha !

- Ảnh mô phỏng protues.

- Đây là code chương trình.

/*
 * File:   LM35.c
 * Author: Dell
 * my blog http://xcvn.blogspot.com
 * Created on November 21, 2015, 10:10 AM
 */
#include <stdio.h>
#include <stdlib.h>
#define _XTAL_FREQ 4000000
#define RS RD2
#define EN RD3
#define D4 RD4
#define D5 RD5
#define D6 RD6
#define D7 RD7
#include <xc.h>
#include "LCD.h"
// CONFIG1
#pragma config FOSC = XT        // Oscillator Selection bits (HS oscillator: High-speed crystal/resonator on RA6/OSC2/CLKOUT and RA7/OSC1/CLKIN)
#pragma config WDTE = OFF       // Watchdog Timer Enable bit (WDT disabled and can be enabled by SWDTEN bit of the WDTCON register)
#pragma config PWRTE = OFF      // Power-up Timer Enable bit (PWRT disabled)
#pragma config MCLRE = OFF      // RE3/MCLR pin function select bit (RE3/MCLR pin function is digital input, MCLR internally tied to VDD)
#pragma config CP = OFF         // Code Protection bit (Program memory code protection is disabled)
#pragma config CPD = OFF        // Data Code Protection bit (Data memory code protection is disabled)
#pragma config BOREN = OFF      // Brown Out Reset Selection bits (BOR disabled)
#pragma config IESO = OFF       // Internal External Switchover bit (Internal/External Switchover mode is disabled)
#pragma config FCMEN = OFF      // Fail-Safe Clock Monitor Enabled bit (Fail-Safe Clock Monitor is disabled)
#pragma config LVP = OFF        // Low Voltage Programming Enable bit (RB3 pin has digital I/O, HV on MCLR must be used for programming)
// CONFIG2
#pragma config BOR4V = BOR40V   // Brown-out Reset Selection bit (Brown-out Reset set to 4.0V)
#pragma config WRT = OFF        // Flash Program Memory Self Write Enable bits (Write protection off)
void ADCinit (void);
unsigned int ReadADC (void);
unsigned int ADCvalue = 0;
unsigned int Temp = 0;
char s[30];
void main(void) 
{
    TRISD = 0X00;
    PORTD = 0;
    ADCinit();
    Lcd_Init();
    Lcd_Set_Cursor(1,4);
    Lcd_Write_String("DEMO LM335");
    Lcd_Set_Cursor(2,2);
    Lcd_Write_String("BY LAM 3 NGON");
    __delay_ms(1000);
    Lcd_Clear();
    while(1)
    {
    ADCvalue = ReadADC();
    Temp = ((5000.0f/1023*ADCvalue)/10) - 273;
    // cong thuc doi sang do F = Temp*1.8 + 32;
    sprintf(s,"Temp =%3u",Temp);
    Lcd_Set_Cursor(1,1);
    Lcd_Write_String(s);  
    Lcd_Set_Cursor(1,10);
    Lcd_Write_Char(223);
    Lcd_Set_Cursor(1,11);
    Lcd_Write_String("C");
    }
}
void ADCinit (void)// adc
{
    // chon tan so clock cho bo adc
    ADCON0bits.ADCS1 = 0, ADCON0bits.ADCS0 = 1;
    // chon kenh ADC
    ADCON0bits.CHS0 = 0, ADCON0bits.CHS1 = 0, ADCON0bits.CHS2 = 0, ADCON0bits.CHS3 = 0;    
    // chon cach luu data
    ADCON1bits.ADFM = 1;
    // cap nguon cho khoi adc
    ADCON0bits.ADON = 1;
}
unsigned int ReadADC (void)// doc len 7 doan
{
    unsigned int TempValue = 0;
    ADCON0bits.GO_nDONE = 1;
    while(ADCON0bits.GO_nDONE);
    TempValue = ADRESH*256 + ADRESL;
    return (TempValue);

}

- Link download project Click here