unsigned int compArrays(void)
{
    unsigned int correct=0;     //number of matching knocks
    unsigned int secret;        //programmed knock value
    unsigned int listen;        //sensed knock value
    unsigned int error;         //allowable percent error
    char k=0;
    secret=knock[PROGRAM][k];
    listen=knock[LISTEN][k];
    while((k<MAX_KNOCKS)&&(secret!=0)&&(listen!=0)) //check individual times and see if they're within 25% error
    {
        error=secret>>4;
        if((secret+error)>knock[LISTEN][k]>(secret-error))  //if within allowable error...
        {
            correct++;      //increase number of correct knock times
        }
        k++;
    }
    if(correct==knockNumber)        //if number of correct knocks match number of knocks...
    {
        char a;
        for(a=0; a<3; a++)      //flash green LED a few times
        {
            GREEN_LED=1;
            Delay10KTCYx(3);
            GREEN_LED=0;
            Delay10KTCYx(5);
        }
        unlockDoor();           //proceed to unlock door
    }
    else                    //if incorrect...
    {
        char b;
        for(b=0; b<3; b++)      //flash red LED a few times
        {
            RED_LED=1;
            Delay10KTCYx(3);
            RED_LED=0;
            Delay10KTCYx(5);
        }
    }
}