/*********************************************************************
 *
 *               Funzioni protocollo ONEWIRE
 *
 ********************************************************************/
#include "compiler.h"
#include "onewire.h"
#include <delays.h>


/*********************************************************************
 * Funzione:        unsigned char OWReset(void)
 *
 * Input:           Nessuno
 * Output:          1 = Dispositivo presente
 *                  0 = Dispositivo non presente
 * Descrizione:     Reset ONWIRE
 *
 ********************************************************************/
unsigned char OWReset(void)
{
    unsigned char pd;

    pd = 0;
    TRISBbits.TRISB5 = 0;
    PORTBbits.RB5 = 0;
    Delay10TCYx(240);
    TRISBbits.TRISB5 = 1;
    Delay10TCYx(40);
    if (PORTBbits.RB5 ==0)    
    pd = 1;
    Delay10TCYx(200);
    return pd;
}

/*********************************************************************
 * Funzione:        void OWTX(unsigned char DATO)
 *
 * Input:           Byte da inviare
 * Output:          Nessuno
 * Descrizione:     Invia un byte al dispositivo ONWIRE
 *
 ********************************************************************/
void OWTX(unsigned char DATO)
{
 unsigned char j;
 
 for (j=0;j<8;j++)
 {
    if ((DATO >> j) & 0x01)
    {
     TRISBbits.TRISB5 = 0;
     PORTBbits.RB5 = 0;
     Delay10TCYx(3);
     TRISBbits.TRISB5 = 1;
     Delay10TCYx(37);
     TRISBbits.TRISB5 = 1;
     Delay10TCYx(1); 
     }    
    else
    {
     TRISBbits.TRISB5 = 0;
     PORTBbits.RB5 = 0;
     Delay10TCYx(40);
     TRISBbits.TRISB5 = 1;
     Delay10TCYx(1); 
     }
  }
}


/*********************************************************************
 * Funzione:        unsigned char OWRX(void)
 *
 * Input:           Nessuno
 * Output:          Byte ricevuto
 * Descrizione:     Riceve un byte dal dispositivo ONWIRE
 *
 ********************************************************************/
unsigned char OWRX(void)
{
 unsigned char j,a,b;

 a=0;
 b=0;
 for (j=0;j<8;j++)
 {
     PORTBbits.RB5 = 0;
     TRISBbits.TRISB5 = 0;
     Delay10TCYx(2);
     TRISBbits.TRISB5 = 1;
     Delay10TCYx(2);
     a = PORTBbits.RB5;  
     a <<= j;
     b |= a;
     Delay10TCYx(36);
  }    
return b;
}    

/*********************************************************************
 * Funzione:        unsigned char OWRX1(void)
 *
 * Input:           Nessuno
 * Output:          Bit ricevuto
 * Descrizione:     Riceve un bit dal dispositivo ONWIRE
 *
 ********************************************************************/
unsigned char OWRX1(void)
{
 unsigned char a;

     a=0;
     PORTBbits.RB5 = 0;
     TRISBbits.TRISB5 = 0;
     Delay10TCYx(2);
     TRISBbits.TRISB5 = 1;
     Delay10TCYx(2);
     a = PORTBbits.RB5;
     Delay10TCYx(36);  
     return a;
}