#include <avr/io.h>
#include <avr/interrupt.h>
#include <stdlib.h>


    //////////////////////////////////////////////////////////////
    //               QuizMaster Firmware                        //
    //      --------------------------------------              //
    //            (c) 2008 by Hubersoft.net                     //
    //                                                          //
    //          Taster: PB0...PB3                               //
    //          Reset:  PD6                                     //
    //          Lampen: PD0...PD3                               //
    //          Summer: PB4                                     //
    //          LED: PA0, PA1                                   //
    //                                                          //
    //////////////////////////////////////////////////////////////


//8 MHz interner Oszillator

//***********************************************************************************//

#define sbi(ADDRESS,BIT) (ADDRESS |= (1<<BIT))
#define cbi(ADDRESS,BIT) (ADDRESS &= ~(1<<BIT))

//***********************************************************************************//

void delay(unsigned int ms)          //ms Millisekunden warten, geht bis 
{
  register unsigned int a, b, c;
  for (a=ms; a>0; --a)
  for (b=212; b>0; --b)
  for (c=255; c>0; --c);
}

//***********************************************************************************//

void udelay(unsigned int ms)          //kürzer warten
{
  register unsigned int a, c;
  for (a=ms; a>0; --a)
  for (c=255; c>0; --c);
}

//***********************************************************************************//

void setlampe(unsigned char nr)          //Schaltet Lampen ein und aus
{
  PORTD=64;
  if (nr<=3) PORTD|=(1<<nr);
}

//***********************************************************************************//

void setled(unsigned char status)          //Schaltet LED grün/rot: 0=rot, Rest grün
{
  if (status==0) PORTA=2; else PORTA=1;
}

//***********************************************************************************//

unsigned char getbutton(void)          //Ermittelt den gedrückten Knopf, keiner=255
{
  unsigned char button=255;

  if ((PIND&64)==0) button=4;  //Resettaster
  if ((PINB&1)==0) button=0;   //Lampe 1
  if ((PINB&2)==0) button=1;   //Lampe 2
  if ((PINB&4)==0) button=2;   //Lampe 3
  if ((PINB&8)==0) button=3;   //Lampe 4
  return button;
}

//***********************************************************************************//

void makesound(void)
{
  unsigned int w;
  unsigned char z;
  for (w=0; w<170; w++)
   for (z=0; z<3; z++){
     sbi(PORTB, 4);
     udelay((w*w)/100+10);
     cbi(PORTB, 4);
     udelay((w*w)/100+10);
    }
}

//***********************************************************************************//

unsigned char w;

int main( void )
{ 
  unsigned char button=0;

  DDRB=16;     //Taster in, Summer out
  DDRD=15;     //Lampen out, Reset button in
  DDRA=3;      //LED out
  PORTA=0;     //LED aus
  PORTB=255;   //Taster pullups aus (sind in Hardware), Summer aus
  PORTD=64;    //Lampen aus, Reset pullup on
  setled(1);
  delay(10);
  for(;;) {
    button=getbutton();
    if (button<4) {
     setlampe(button);
     setled(0);
     makesound();
     delay(10);
     while (getbutton()!=4);
     delay(10);
    }
    setled(1);
    setlampe(5);
  }
}
//***********************************************************************************//