HCSR04.h

00001 /**
00002  * @author Nestor Pereira-Neto  Team: SalvadorEngenharia
00003  *
00004  * @section LICENSE
00005  *
00006  * Copyright (c) 2010 ARM Limited
00007  *
00008  * Permission is hereby granted, free of charge, to any person obtaining a copy
00009  * of this software and associated documentation files (the "Software"), to deal
00010  * in the Software without restriction, including without limitation the rights
00011  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00012  * copies of the Software, and to permit persons to whom the Software is
00013  * furnished to do so, subject to the following conditions:
00014  *
00015  * The above copyright notice and this permission notice shall be included in
00016  * all copies or substantial portions of the Software.
00017  *
00018  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00019  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00020  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00021  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00022  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00023  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00024  * THE SOFTWARE.
00025  *
00026  * @section DESCRIPTION
00027  *
00028  * Biblioteca para uso do sonar HC-SR04, possui rotinas para permitir medições 
00029  * de distências retornado valores em centímetros, polegadas ou o tempo 
00030  * percorrido pelo som (em microsegundos).
00031  * Esta biblioteca pode ser usada com qualquer pino do microcontrolador.
00032  */
00033 
00034 
00035 #ifndef HCSR04_H
00036 #define HCSR04_H
00037 
00038 #include "mbed.h"
00039 
00040 
00041 
00042 /** 
00043  * Sonar HC-SR04 example.
00044  * @code
00045  * #include "mbed.h"
00046  * #include "HCSR04.h"
00047  *
00048  * DigitalOut myled(LED1);
00049  * Serial pc(USBTX,USBRX);     
00050  *
00051  * HCSR04 sonar(PTD5, PTA13);
00052  *
00053  * int main() {
00054  *     while(1) {
00055  *         printf("Distancia detectada pelo sensor Frente %.2f cm \n", sonar.getCm()); 
00056  *         wait_ms(1000);
00057  *     }
00058  * }
00059  *
00060  * @endcode
00061 */
00062 
00063 class HCSR04 {    
00064     public:    
00065         /** Constructor, create HCSR04 instance 
00066           *
00067           * @param trigger TRIG pin
00068           * @param echo ECHO pin
00069           */
00070         HCSR04(PinName trigger, PinName echo);
00071  
00072         /** It make a reading of the sonar Faz uma leitura do sonar
00073           * 
00074           * @returns Tempo do pulso echo em microsegundos*/
00075         float readEcho(void);
00076         
00077         /** It messures the distance in centimeter "cm" 
00078           *
00079           *@returns Distance in centimeter
00080           */
00081         float getCm(void);
00082         
00083         /** Mede a distência em polegadas "in" 
00084           *
00085           *@returns Distência em in*/
00086         float getIn(void);
00087         
00088     private:
00089         float tdist;        //Leitura do tempo transcorrido
00090         float distcm;       //Guarda o valor da distanciância em centímetros
00091         float distin;       //Guarda o valor da distência em polegadas
00092         
00093         DigitalOut _t;      //Configuração do pino de Trigger  
00094         DigitalIn _e;       //Configuração do pino de Echo
00095         Timer _tempo;       //Cria um objeto timer
00096         
00097 };
00098 
00099 #endif