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EXEMPLO

/*

   HC-SR04 - Sensor Ultrassonico
   MCU: PIC18F4550
   CLOCK: HS + PLL, 48MHz
*/

#include "HC-SR04.h"

// LCD module connections
sbit LCD_RS at RB4_bit;
sbit LCD_EN at RB5_bit;
sbit LCD_D4 at RB0_bit;
sbit LCD_D5 at RB1_bit;
sbit LCD_D6 at RB2_bit;
sbit LCD_D7 at RB3_bit;

sbit LCD_RS_Direction at TRISB4_bit;
sbit LCD_EN_Direction at TRISB5_bit;
sbit LCD_D4_Direction at TRISB0_bit;
sbit LCD_D5_Direction at TRISB1_bit;
sbit LCD_D6_Direction at TRISB2_bit;
sbit LCD_D7_Direction at TRISB3_bit;
// End LCD module connections

sbit HCSR04_Trigger at RD0_Bit;
sbit HCSR04_Echo at RD1_Bit;
sbit HCSR04_Trigger_Direction at TRISD0_Bit;
sbit HCSR04_Echo_Direction at TRISD1_Bit;

char text[8];
unsigned Distancia;
//factor = 1 / ( ( 4 * Prescaler ) / Clock )
const float factor = 1.5;

void main()
{
    ADCON1 = 0x0F;
    
    //0 - prescaler 1:1
    //1 - prescaler 1:2
    //2 - prescaler 1:4
    //3 - prescaler 1:8
    HCSR04_Init(3);
    
    Lcd_Init();
    Lcd_Cmd(_LCD_CLEAR);               // Clear display
    Lcd_Cmd(_LCD_CURSOR_OFF);          // Cursor off
  
    while(1)
    {
      Distancia = HCSR04_Read();
      WordToStrWithZeros( Distancia, text );
      Lcd_Out( 1, 1, "Dist.: " )
      Lcd_Out_CP( text );
      Lcd_Out_CP( "mm" );
      Delay_ms( 300 );
    }
}