PIC16 C Sample: 1-Wire

Environment: MPLAB X IDE + HI TECH Compiler for PIC16

#define OW_TRIS TRISA0      //Port mode register, 1=input,0=output
#define OW_PORT RA0         //Pin connected to 1-wire bus

int owReset(void)
{
    char state = 0;
    OW_TRIS = 0;        //Set as output
    OW_PORT = 0;        //Drive Low
    __delay_us(480);
    OW_TRIS = 1;        //Release, Set back as input
    __delay_us(70);
    state = !OW_PORT;   //If devices are present, it will keep the pin low
                        //! will invert 1=0, 0=1
    __delay_us(410);
    return state;       //Returns 1 if devices are present
}

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