//*************************************** 
//***************************************
//   
//  AVRLIB-DEMO
//  For avrlib and avrmini development board.
//  
//
//  File:     buttons_sensors.c
//  Author:   Michael Gurevich
//  Date:     Nov. 3, 2002


#include <io.h>
#include <interrupt.h>
#include <sig-avr.h>

#include "global.h"
#include "midi.h"
#include "uart.h"
#include "timer.h"
#include "a2d.h"

#define DEBOUNCE_THRESHOLD 10


//returns 1 if button is down, 0 otherwise
u08 checkButton(u08 button) {

  //array of debounce counters
  static u08 buttonUpCounter[9];
  static u08 buttonDownCounter[9];

  //button status doesn't change until ..Counter == DEBOUNCE_THRESHOLD
  static u08 buttonDown[9];
 
  //button 8 is on a different port, so check it separately
  if (button == 8) { 
    if (! bit_is_set(PIND,0)) { //button is pressed
	    //check if DEBOUNCE_THRESHOLD has been reached
	    if (buttonDown[button]==0){
		if (buttonDownCounter[button]++ == DEBOUNCE_THRESHOLD){
		    buttonDown[button] = 1;
			buttonUpCounter[button] = 0;
			timer0ClearOverflowCount();
		}
	    }
	} 

    else { 
      if (buttonDown[button]==1){
	if (buttonUpCounter[button]++ == DEBOUNCE_THRESHOLD){
	  buttonDown[button] = 0;
	  buttonDownCounter[button] = 0;
	}
      }
    }
  }
  
  else {

    if (! bit_is_set(PINC,button)) { //button is pressed
      //check if DEBOUNCE_THRESHOLD has been reached
      if (buttonDown[button]==0){
	if (buttonDownCounter[button]++ == DEBOUNCE_THRESHOLD){
	  buttonDown[button] = 1;
	  buttonUpCounter[button] = 0;
	  timer0ClearOverflowCount();
	}
      }
    } 
    else { 
      if (buttonDown[button]==1){
	if (buttonUpCounter[button]++ == DEBOUNCE_THRESHOLD){
	  buttonDown[button] = 0;
	  buttonDownCounter[button] = 0;
	}
      }
    }
  }

return buttonDown[button];	  
}	


int main(void)
{

	u08 i;
	u08 buttonstate[9] = {0, 0, 0, 0, 0, 0, 0, 0, 0};
	u08 temp;
	s16 a2dvalue[4];

	// these are for filtering
	s16 a2d_filt[4];
       	s16 a2d_last[4] = {0, 0, 0, 0};

	uartInit();     
	midiInit();
	timerInit();
	a2dInit();
	a2dSetReference(0x01);

	//set a2d pins to inputs
	outb(DDRA, 0x00);   

	// set button pins as inputs
	outb(DDRC, 0x00);
	
	// loop forever
	while(1) {

	  for(i=0;i<9;i++){
	    temp = checkButton(i);
	    if (temp != buttonstate[i])
	      {
		buttonstate[i] = !buttonstate[i];
		midiNoteOnOut(i, buttonstate[i], 1);
	      }
	    
	    if (i<4){

	      //filter the a2d values
	      a2dvalue[i] = a2dConvert10bit(i) - 512;
	      a2d_filt[i] = (31*a2d_last[i] + a2dvalue[i])/32;
	      a2d_last[i] = a2d_filt[i];
	      a2d_filt[i]+=512;
	      a2dvalue[i]+=512;

	      //send raw a2d
	      midiControlChangeOut((a2dvalue[i]>>7),(a2dvalue[i] & 0x7F),i); 

	      // send filtered a2d
	      //  midiControlChangeOut((a2d_filt[i]>>7),(a2d_filt[i] & 0x7F),i+4); 
	    }
	  }
	  timerPause(2);

	}

	return 0;
}