// CC-by-www.Electrosmash.com
// Based on OpenMusicLabs and GFB previous works.
// pedalshield_metronome.ino plays a beep (togheter with the LED) like a metronome.
// pressing the pushbutton_1 or 2 changes the speed.

const byte waveform[]=
{
0x80,0x80,0x81,0x82,0x83,0x83,0x84,0x85,0x86,0x87,0x87,0x88,0x89,0x8a,0x8a,0x8b,
0x8c,0x8d,0x8e,0x8e,0x8f,0x90,0x91,0x91,0x92,0x93,0x94,0x95,0x95,0x96,0x97,0x98,
0x98,0x99,0x9a,0x9b,0x9b,0x9c,0x9d,0x9e,0x9f,0x9f,0xa0,0xa1,0xa2,0xa2,0xa3,0xa4,
0xa5,0xa5,0xa6,0xa7,0xa8,0xa8,0xa9,0xaa,0xaa,0xab,0xac,0xad,0xad,0xae,0xaf,0xb0,
0xb0,0xb1,0xb2,0xb2,0xb3,0xb4,0xb5,0xb5,0xb6,0xb7,0xb7,0xb8,0xb9,0xba,0xba,0xbb,
0xbc,0xbc,0xbd,0xbe,0xbe,0xbf,0xc0,0xc0,0xc1,0xc2,0xc2,0xc3,0xc4,0xc4,0xc5,0xc6,
0xc6,0xc7,0xc8,0xc8,0xc9,0xca,0xca,0xcb,0xcc,0xcc,0xcd,0xcd,0xce,0xcf,0xcf,0xd0,
0xd0,0xd1,0xd2,0xd2,0xd3,0xd3,0xd4,0xd5,0xd5,0xd6,0xd6,0xd7,0xd7,0xd8,0xd9,0xd9,
0xda,0xda,0xdb,0xdb,0xdc,0xdc,0xdd,0xde,0xde,0xdf,0xdf,0xe0,0xe0,0xe1,0xe1,0xe2,
0xe2,0xe3,0xe3,0xe4,0xe4,0xe5,0xe5,0xe6,0xe6,0xe6,0xe7,0xe7,0xe8,0xe8,0xe9,0xe9,
0xea,0xea,0xea,0xeb,0xeb,0xec,0xec,0xed,0xed,0xed,0xee,0xee,0xef,0xef,0xef,0xf0,
0xf0,0xf0,0xf1,0xf1,0xf1,0xf2,0xf2,0xf2,0xf3,0xf3,0xf3,0xf4,0xf4,0xf4,0xf5,0xf5,
0xf5,0xf6,0xf6,0xf6,0xf7,0xf7,0xf7,0xf7,0xf8,0xf8,0xf8,0xf8,0xf9,0xf9,0xf9,0xf9,
0xfa,0xfa,0xfa,0xfa,0xfa,0xfb,0xfb,0xfb,0xfb,0xfb,0xfc,0xfc,0xfc,0xfc,0xfc,0xfc,
0xfd,0xfd,0xfd,0xfd,0xfd,0xfd,0xfd,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,
0xfe,0xfe,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,
0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xfe,
0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfe,0xfd,0xfd,0xfd,0xfd,0xfd,0xfd,0xfd,
0xfd,0xfc,0xfc,0xfc,0xfc,0xfc,0xfb,0xfb,0xfb,0xfb,0xfb,0xfb,0xfa,0xfa,0xfa,0xfa,
0xf9,0xf9,0xf9,0xf9,0xf8,0xf8,0xf8,0xf8,0xf7,0xf7,0xf7,0xf7,0xf6,0xf6,0xf6,0xf5,
0xf5,0xf5,0xf5,0xf4,0xf4,0xf4,0xf3,0xf3,0xf3,0xf2,0xf2,0xf2,0xf1,0xf1,0xf1,0xf0,
0xf0,0xef,0xef,0xef,0xee,0xee,0xee,0xed,0xed,0xec,0xec,0xeb,0xeb,0xeb,0xea,0xea,
0xe9,0xe9,0xe8,0xe8,0xe8,0xe7,0xe7,0xe6,0xe6,0xe5,0xe5,0xe4,0xe4,0xe3,0xe3,0xe2,
0xe2,0xe1,0xe1,0xe0,0xe0,0xdf,0xdf,0xde,0xde,0xdd,0xdd,0xdc,0xdc,0xdb,0xdb,0xda,
0xd9,0xd9,0xd8,0xd8,0xd7,0xd7,0xd6,0xd5,0xd5,0xd4,0xd4,0xd3,0xd3,0xd2,0xd1,0xd1,
0xd0,0xd0,0xcf,0xce,0xce,0xcd,0xcc,0xcc,0xcb,0xcb,0xca,0xc9,0xc9,0xc8,0xc7,0xc7,
0xc6,0xc5,0xc5,0xc4,0xc3,0xc3,0xc2,0xc1,0xc1,0xc0,0xbf,0xbf,0xbe,0xbd,0xbd,0xbc,
0xbb,0xbb,0xba,0xb9,0xb9,0xb8,0xb7,0xb6,0xb6,0xb5,0xb4,0xb4,0xb3,0xb2,0xb1,0xb1,
0xb0,0xaf,0xaf,0xae,0xad,0xac,0xac,0xab,0xaa,0xa9,0xa9,0xa8,0xa7,0xa6,0xa6,0xa5,
0xa4,0xa3,0xa3,0xa2,0xa1,0xa0,0xa0,0x9f,0x9e,0x9d,0x9d,0x9c,0x9b,0x9a,0x9a,0x99,
0x98,0x97,0x96,0x96,0x95,0x94,0x93,0x93,0x92,0x91,0x90,0x90,0x8f,0x8e,0x8d,0x8c,
0x8c,0x8b,0x8a,0x89,0x88,0x88,0x87,0x86,0x85,0x85,0x84,0x83,0x82,0x81,0x81,0x80,
0x7f,0x7e,0x7e,0x7d,0x7c,0x7b,0x7a,0x7a,0x79,0x78,0x77,0x77,0x76,0x75,0x74,0x73,
0x73,0x72,0x71,0x70,0x6f,0x6f,0x6e,0x6d,0x6c,0x6c,0x6b,0x6a,0x69,0x69,0x68,0x67,
0x66,0x65,0x65,0x64,0x63,0x62,0x62,0x61,0x60,0x5f,0x5f,0x5e,0x5d,0x5c,0x5c,0x5b,
0x5a,0x59,0x59,0x58,0x57,0x56,0x56,0x55,0x54,0x53,0x53,0x52,0x51,0x50,0x50,0x4f,
0x4e,0x4e,0x4d,0x4c,0x4b,0x4b,0x4a,0x49,0x49,0x48,0x47,0x46,0x46,0x45,0x44,0x44,
0x43,0x42,0x42,0x41,0x40,0x40,0x3f,0x3e,0x3e,0x3d,0x3c,0x3c,0x3b,0x3a,0x3a,0x39,
0x38,0x38,0x37,0x36,0x36,0x35,0x34,0x34,0x33,0x33,0x32,0x31,0x31,0x30,0x2f,0x2f,
0x2e,0x2e,0x2d,0x2c,0x2c,0x2b,0x2b,0x2a,0x2a,0x29,0x28,0x28,0x27,0x27,0x26,0x26,
0x25,0x24,0x24,0x23,0x23,0x22,0x22,0x21,0x21,0x20,0x20,0x1f,0x1f,0x1e,0x1e,0x1d,
0x1d,0x1c,0x1c,0x1b,0x1b,0x1a,0x1a,0x19,0x19,0x18,0x18,0x17,0x17,0x17,0x16,0x16,
0x15,0x15,0x14,0x14,0x14,0x13,0x13,0x12,0x12,0x11,0x11,0x11,0x10,0x10,0x10,0xf,
0xf,0xe,0xe,0xe,0xd,0xd,0xd,0xc,0xc,0xc,0xb,0xb,0xb,0xa,0xa,0xa,
0xa,0x9,0x9,0x9,0x8,0x8,0x8,0x8,0x7,0x7,0x7,0x7,0x6,0x6,0x6,0x6,
0x5,0x5,0x5,0x5,0x4,0x4,0x4,0x4,0x4,0x4,0x3,0x3,0x3,0x3,0x3,0x2,
0x2,0x2,0x2,0x2,0x2,0x2,0x2,0x1,0x1,0x1,0x1,0x1,0x1,0x1,0x1,0x1,
0x1,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,
0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x0,0x1,0x1,
0x1,0x1,0x1,0x1,0x1,0x1,0x1,0x1,0x1,0x2,0x2,0x2,0x2,0x2,0x2,0x2,
0x3,0x3,0x3,0x3,0x3,0x3,0x4,0x4,0x4,0x4,0x4,0x5,0x5,0x5,0x5,0x5,
0x6,0x6,0x6,0x6,0x7,0x7,0x7,0x7,0x8,0x8,0x8,0x8,0x9,0x9,0x9,0xa,
0xa,0xa,0xb,0xb,0xb,0xc,0xc,0xc,0xd,0xd,0xd,0xe,0xe,0xe,0xf,0xf,
0xf,0x10,0x10,0x10,0x11,0x11,0x12,0x12,0x12,0x13,0x13,0x14,0x14,0x15,0x15,0x15,
0x16,0x16,0x17,0x17,0x18,0x18,0x19,0x19,0x19,0x1a,0x1a,0x1b,0x1b,0x1c,0x1c,0x1d,
0x1d,0x1e,0x1e,0x1f,0x1f,0x20,0x20,0x21,0x21,0x22,0x23,0x23,0x24,0x24,0x25,0x25,
0x26,0x26,0x27,0x28,0x28,0x29,0x29,0x2a,0x2a,0x2b,0x2c,0x2c,0x2d,0x2d,0x2e,0x2f,
0x2f,0x30,0x30,0x31,0x32,0x32,0x33,0x33,0x34,0x35,0x35,0x36,0x37,0x37,0x38,0x39,
0x39,0x3a,0x3b,0x3b,0x3c,0x3d,0x3d,0x3e,0x3f,0x3f,0x40,0x41,0x41,0x42,0x43,0x43,
0x44,0x45,0x45,0x46,0x47,0x48,0x48,0x49,0x4a,0x4a,0x4b,0x4c,0x4d,0x4d,0x4e,0x4f,
0x4f,0x50,0x51,0x52,0x52,0x53,0x54,0x55,0x55,0x56,0x57,0x57,0x58,0x59,0x5a,0x5a,
0x5b,0x5c,0x5d,0x5d,0x5e,0x5f,0x60,0x60,0x61,0x62,0x63,0x64,0x64,0x65,0x66,0x67,
0x67,0x68,0x69,0x6a,0x6a,0x6b,0x6c,0x6d,0x6e,0x6e,0x6f,0x70,0x71,0x71,0x72,0x73,
0x74,0x75,0x75,0x76,0x77,0x78,0x78,0x79,0x7a,0x7b,0x7c,0x7c,0x7d,0x7e,0x7f,0x80,
};

//defining harware resources.
#define LED 13
#define FOOTSWITCH 12
#define TOGGLE 2
#define PUSHBUTTON_1 A5
#define PUSHBUTTON_2 A4

//defining the output PWM parameters
#define PWM_FREQ 0x00FF // pwm frequency - 31.3KHz
#define PWM_MODE 0 // Fast (1) or Phase Correct (0)
#define PWM_QTY 2 // 2 PWMs in parallel

//other variables
int input; 
long delay_time=20000;
int counter=0;
int sample=0;

void setup() {
  //setup IO
  pinMode(FOOTSWITCH, INPUT_PULLUP);
  pinMode(TOGGLE, INPUT_PULLUP);
  pinMode(PUSHBUTTON_1, INPUT_PULLUP);
  pinMode(PUSHBUTTON_2, INPUT_PULLUP);
  pinMode(LED, OUTPUT);
  
  // setup ADC
  ADMUX = 0x60; // left adjust, adc0, internal vcc
  ADCSRA = 0xe5; // turn on adc, ck/32, auto trigger
  ADCSRB = 0x07; // t1 capture for trigger
  DIDR0 = 0x01; // turn off digital inputs for adc0

  // setup PWM
  TCCR1A = (((PWM_QTY - 1) << 5) | 0x80 | (PWM_MODE << 1)); //
  TCCR1B = ((PWM_MODE << 3) | 0x11); // ck/1
  TIMSK1 = 0x20; // interrupt on capture interrupt
  ICR1H = (PWM_FREQ >> 8);
  ICR1L = (PWM_FREQ & 0xff);
  DDRB |= ((PWM_QTY << 1) | 0x02); // turn on outputs
  sei(); // turn on interrupts - not really necessary with arduino
  }

void loop() 
{
  
//BEEP PART: Enable Interruption which makes the sinewave.   
digitalWrite(LED, HIGH); 
sei(); // turn on interrupts - not really necessary with arduino  
delay(50); //the beep has a constant time of 50ms.
 
//SILENT PART: Disabling Interruption which makes the sinewave.
digitalWrite(LED, LOW); 
cli();
//IC_DisableIRQ(TC4_IRQn);
 
sample=0;
delay(delay_time);
 
}

ISR(TIMER1_CAPT_vect) 
{
  
counter++; //to save resources, the pushbuttons are checked every 100 times.
if(counter==1000)
{ 
counter=0;
if (!digitalRead(PUSHBUTTON_1)) {
  if (delay_time<2000000)delay_time=delay_time+1000; //increase the vol
 //   digitalWrite(LED, LOW); //blinks the led
    }

    if (!digitalRead(PUSHBUTTON_2)) {
  if (delay_time>600)delay_time=delay_time-1000; //decrease vol
//  digitalWrite(LED, LOW); //blinks the led
    }
}

input = waveform[sample];//((ADC_high << 8) | ADC_low) + 0x8000; // make a signed 16b value
sample=sample+20;
if(sample>=1023)sample=0;

  //write the PWM signal
 OCR1AL =waveform[sample];
 OCR1BL = waveform[sample];
}