Fabio Durigon / SRF02

Based on Robinson Lopez Monzon library: This library contains all the functions necesary to perform an application using the SRF02 sensor. Modified by Dury: replaced wait() functions that are not usefull for program performance. Esta librería contiene los métodos necesarios para poder configurar todos los parámetros del sensor SRF02.

Fork of SRF02 by Fabio Durigon

SRF02.cpp

Committer:
dury
Date:
2013-02-09
Revision:
1:d624771f0bd3
Parent:
0:559a18121e83

File content as of revision 1:d624771f0bd3:

#include "SRF02.h"

SRF02::SRF02(PinName sda, PinName scl, int addr) : m_i2c(sda, scl), m_addr(addr)
{
}

SRF02::~SRF02()
{
}

//Get the data in centimeters
int SRF02::readcm()
{
 char cmd[2];
 char eco_high[1],eco_low[1]; //this is because the sensor, sends the data in tow bytes, and  you have tu read from two different registers 0x02 and 0x03;


    // Get range data from SRF02 in centimeters
    cmd[0] = 0x00;                      
    cmd[1] = 0x51;                     
    m_i2c.write(m_addr, cmd, 2);          

    wait_ranging();


    cmd[0] = 0x02;                        
    m_i2c.write(m_addr, cmd, 1, 1);        
    m_i2c.read(m_addr, eco_high, 1);            
    
    cmd[0] = 0x03;
    m_i2c.write(m_addr,cmd,1,1);
    m_i2c.read(m_addr,eco_low,1);

    int range = (eco_high[0]<<8)|eco_low[0];

    return range;
}

//Get the data in inches
int SRF02::readinch()
{
 char cmd[2];
 char eco_high[1],eco_low[1]; //this is because the sensor, sends the data in tow bytes, and  you have tu read from two different registers 0x02 and 0x03;

    cmd[0] = 0x00;                      
    cmd[1] = 0x50;                     
    m_i2c.write(m_addr, cmd, 2);          

    wait_ranging();
    
    cmd[0] = 0x02;                        
    m_i2c.write(m_addr, cmd, 1, 1);        
    m_i2c.read(m_addr, eco_high, 1);            
    
    cmd[0] = 0x03;
    m_i2c.write(m_addr,cmd,1,1);
    m_i2c.read(m_addr,eco_low,1);

    int range = (eco_high[0]<<8)|eco_low[0];

    return range;
}

//Change adress of the device. Remember to have only one sensor conected to execute this method.
void SRF02::change_addr(char new_addr)
{
 char cmd[2];
    
    cmd[0]=0x00;
    cmd[1]=0xA0;
    m_i2c.write(m_addr,cmd,2);
    cmd[0]=0x00;
    cmd[1]=0xAA;
    m_i2c.write(m_addr,cmd,2);
    cmd[0]=0x00;
    cmd[1]=0xA5;
    m_i2c.write(m_addr,cmd,2);
    cmd[0]=0x00;
    cmd[1]=new_addr;
    m_i2c.write(m_addr,cmd,2);
    
    }
    
void SRF02::wait_ranging(void)
{
 char eco;
 
    do {
        eco=m_i2c.read(1);
    }while(eco == 0xff);    
}