How to start programming pedalSHIELD

Yes, thank you !
I had just done the part under "while," now it's starting to make sense.
void loop ()
{
  // Read the ADCs
  while ((ADC -> ADC_ISR & 0x1CC3)! = 0x1CC3); // expects the conversion of ADC 0, 1, 6, 7, 8, 9, 10 to complete.
  in_ADC0 = ADC -> ADC_CDR [7] // read data from ADC0
  in_ADC1 = ADC -> ADC_CDR [6] // read data from ADC1
  POT0 = ADC -> ADC_CDR [10] // read data from ADC8
  POT1 = ADC -> ADC_CDR [11] // read data from ADC9
  POT2 = ADC -> ADC_CDR [12] // read data from ADC10
  POT3 = ADC -> ADC_CDR [0]; // read data from ADC7
  POT4 = ADC -> ADC_CDR [1]; // read data from ADC6
  }

Without wanting to bother, but already bothering kk, I would like to know: if the "if" function is used 4 times can they be checked at the same time?
And 2 of them can be executed at the same time?

I'm trying to make an alternative pedal for a college job and I'm using the pedalshield programming as a base (of course I'll cite it as a reference and with all the credits). I intend to make the pedal with 4 effects. 2 of them can be used simultaneously and can be combined in parallel or in series. And for this I feel that here I will find help to make doubts and to progress with this
If I can and will work, as expected, I promise to post here on the site with all the details of execution for whoever wants to mount it.

Below is what I am referring to:


void loop ()
{
  // Read the ADCs
  while ((ADC -> ADC_ISR & 0x1CC3)! = 0x1CC3); // expects the conversion of ADC 0, 1, 6, 7, 8, 9, 10 to complete.
  in_ADC0 = ADC -> ADC_CDR [7] // read data from ADC0
  in_ADC1 = ADC -> ADC_CDR [6] // read data from ADC1
  POT0 = ADC -> ADC_CDR [10] // read data from ADC8
  POT1 = ADC -> ADC_CDR [11] // read data from ADC9
  POT2 = ADC -> ADC_CDR [12] // read data from ADC10
  POT3 = ADC -> ADC_CDR [0]; // read data from ADC7
  POT4 = ADC -> ADC_CDR [1]; // read data from ADC6
  }
 
void TC4_Handler ()
{{
  // We need to get the status to clear it and allow the interrupt to fire again
  TC_GetStatus (TC1, 1);
  
  if (effect_1 == HIGH) // EFFECT 1: Symmetric distortion
  {
 // digitalWrite (LED, LOW);
    upper_threshold = map (POT0, 0, 4095, 4095,! POT0);
    lower_threshold = map (POT0, 0, 4095, 0000, POT0);
    
  // upper_threshold0 =! upper_threshold;
  // lower_threshold0 =! lower_threshold;
 
  if (in_ADC0> = upper_threshold) in_ADC0 = upper_threshold;
  else if (in_ADC0 <lower_threshold) in_ADC0 = lower_threshold;
  // if (in_ADC1> = upper_threshold) in_ADC1 = upper_threshold;
  // else if (in_ADC1 <lower_threshold) in_ADC1 = lower_threshold;
  
  // adjust the volume with POT2 with constant intensity
  out_DAC0 = map (in_ADC0, lower_threshold, upper_threshold, 1, POT4);
 // out_DAC1 = map (in_ADC1, lower_threshold, upper_threshold, 1, POT2);
  
  // Record the DACs
  dacc_set_channel_selection (DACC_INTERFACE, 0) // selects DAC channel 0
  dacc_write_conversion_data (DACC_INTERFACE, out_DAC0) // write to DAC 0
  // dacc_set_channel_selection (DACC_INTERFACE, 1) // select DAC channel 1
  // dacc_write_conversion_data (DACC_INTERFACE, out_DAC1); // writes in DAC 1
  }
  
  if (effect_2 == HIGH) // EFFECT 2: Clean.
  {
    // Add volume feature with POT4
    out_DAC0 = map (in_ADC0,0,4095,1, POT4);
    // out_DAC1 = map (in_ADC1,0,4095,1, POT4);
    
    // Write the DACs
    dacc_set_channel_selection (DACC_INTERFACE, 0); // select DAC channel 0
    dacc_write_conversion_data (DACC_INTERFACE, out_DAC0); // writes in DAC 0
    // dacc_set_channel_selection (DACC_INTERFACE, 1); // select DAC channel 1
    // dacc_write_conversion_data (DACC_INTERFACE, out_DAC1); // writes in DAC 1
    }
    
    if (effect_3 == HIGH) // EFFECT 3: Delay.
  {
    // digitalWrite (LED, LOW);
    
  // Store current readings
  // sDelayBuffer0 [DelayCounter] = in_ADC0;
  sDelayBuffer1 [DelayCounter] = in_ADC1;
  
  // Set the delay depth based on the position of the pot1. $$$$
  Delay_Depth = map (POT2 >> 2.0,1023,1, MAX_DELAY);
  
  // Increse / reset delay counter.
  DelayCounter;
  if (DelayCounter> = Delay_Depth) DelayCounter = 0;
  // out_DAC0 = ((sDelayBuffer0 [DelayCounter]));
  out_DAC1 = ((sDelayBuffer1 [DelayCounter]));
  
  // Add volume feature
  // out_DAC0 = map (out_DAC0,0,4095,1, POT3);
  out_DAC1 = map (out_DAC1,0,4095,1, POT3);
  
  // Write the DACs
  // dacc_set_channel_selection (DACC_INTERFACE, 0); // select DAC channel 0
  // dacc_write_conversion_data (DACC_INTERFACE, out_DAC0); // writes in the DAC
  dacc_set_channel_selection (DACC_INTERFACE, 1); // select DAC channel 1
  dacc_write_conversion_data (DACC_INTERFACE, out_DAC1); // writes in DAC 0
  
  // Clear status allowing the interrupt to be triggered again.
  TC_GetStatus (TC1, 1);
  }}
  
  // void switch_handler ()
  
  // delayMicroseconds (100000); // debouncing protection
  // if (toggle_value! = digitalRead (TOGGLE)) effect;
  // delayMicroseconds (100000); // debouncing protection
    // toggle_value = digitalRead (TOGGLE);
    // if (effect == 1) effect = 0;
    // Delay_Depth = 300; // resets the variable.
    
    if (effect_4 == HIGH) // EFFECT 4: Tremolo.
    {
      // Store current readings in ECHO mode
      DelayBuffer_A [DelayCounter_A] = (in_ADC0 (DelayBuffer_A [DelayCounter_A])) >> 1;
      DelayBuffer_B [DelayCounter_B] = (in_ADC1 (DelayBuffer_B [DelayCounter_B])) >> 1;
      
      // Set the delay depth based on position POT0 and POT1.
      Delay_Depth_A = map (POT2 >> 3,0,512,1, MAX_DELAY_A);
      Delay_Depth_B = map (POT2 >> 3,0,512,1, MAX_DELAY_B);
      
      // Increse / reset delay counter.
      DelayCounter_A;
      DelayCounter_B;
      if (DelayCounter_A> = Delay_Depth_A) DelayCounter_A = 0;
      if (DelayCounter_B> = Delay_Depth_B) DelayCounter_B = 0;
      
      // Calculate the output as the sum of DelayBuffer_A DelayBuffer_B
      // out_DAC0 = (DelayBuffer_A [DelayCounter_A]);
      out_DAC1 = (DelayBuffer_B [DelayCounter_B]);
      
      // Add volume feature based on pot3 position.
      // out_DAC0 = map (out_DAC0,0,4095,1, POT3);
      out_DAC1 = map (out_DAC1,0,4095,1, POT3);
      
      // Write the DACs
      // dacc_set_channel_selection (DACC_INTERFACE, 0); //select DAC channel 0
       // dacc_write_conversion_data (DACC_INTERFACE, out_DAC0); // writes in DAC 0
       dacc_set_channel_selection (DACC_INTERFACE, 1); // select DAC channel 1
       dacc_write_conversion_data (DACC_INTERFACE, out_DAC1); // writes in DAC 1
       }}


2 of these effects will have to work simultaneously. And I'd like to know if it's possible 2 "if" to run at the same time.

I also want help from you with this error that appears when I check:

C: \ Users \ mathe \ AppData \ Local \ Arduino15 \ packages \ arduino \ hardware \ sam \ 1.6.12 \ colors \ arduino \ syscalls_sam3.c: In the '_exit' function:

C: \ Users \ mathe \ AppData \ Local \ Arduino15 \ packages \ arduino \ hardware \ sam \ 1.6.12 \ colors \ arduino \ syscalls_sam3.c: 133: 24: warning: unused parameter 'status' [-Wunused-parameter ]

extern void _exit (int status)

^



No error appears in the code, so I do not know what it can be. Can you help me with this?






This is the full code I am using:

   int in_ADC0, in_ADC1; // variables for 2 values ​​of ADCs (ADC0, ADC1)
   int POT0, POT1, POT2, POT3, POT4, out_DAC0, out_DAC1; // variables for 5 pots (ADC6, ADC7, ADC8, ADC9, ADC10)
   // int LED = 3;
   // int FOOTSWITCH = 7;
   // int TOGGLE = 2;
   int sample, accumulator, count, LFO;

   int effect_1 = 2;
   int effect_2 = 3;
   int effect_3 = 4;
   int effect_4 = 5;
   
  // int toggle_value = 0;
  // int effect = 0;
   
   int upper_threshold, lower_threshold;
   
   #define MAX_DELAY 20000
   uint16_t sDelayBuffer0 [MAX_DELAY];
   uint16_t sDelayBuffer1 [MAX_DELAY];
   unsigned int DelayCounter = 0;
   unsigned int Delay_Depth = MAX_DELAY;
   
   // # define MAX_DELAY 500
   // # define MIN_DELAY 200
   unsigned int count_up = 1;
   int p;
   int switch_handler = 0;

  #define MAX_DELAY_A 10000
  #define MAX_DELAY_B 10000
  uint16_t DelayBuffer_A [MAX_DELAY_A];
  uint16_t DelayBuffer_B [MAX_DELAY_B];
  unsigned int DelayCounter_A = 0;
  unsigned int DelayCounter_B = 0;
  unsigned int Delay_Depth_A, Delay_Depth_B;
 
void setup ()
{
  // * turns the timer on the power management control * /
  pmc_set_writeprotect (false);
  pmc_enable_periph_clk (TC_ID4);
 
  // we want wavesel 01 with RC
  TC_Configure (TC1,1, TC_CMR_WAVE | TC_CMR_WAVSEL_UP_RC | TC_CMR_TCCLKS_TIMER_CLOCK2);
  TC_SetRC (TC1, 1, 238); // define <> interruption rate of 44.1 KHz
  TC_Start (TC1, 1);

   
  // activates the timer interrupts on the timer
  TC1 -> TC_CHANNEL [1]. TC_IER = TC_IER_CPCS;
  TC1 -> TC_CHANNEL [1]. TC_IDR = ~ TC_IER_CPCS;
 
  // * Enables interrupt on null vector interrupt handler * /
  // * TC4_IRQn where 4 is the timer number * timer channels (3) + channel number
  // (= (1 * 3) +1) for timer1 channel1 * /
  NVIC_EnableIRQ (TC4_IRQn);
  
  // ADC Configuration
  ADC -> ADC_MR | = 0x80; // DAC in free running mode.
  ADC -> ADC_CR = 2; // Initiates ADC conversion.
  ADC -> ADC_CHER = 0x1CC3; // Activate ADC channels 0 and 1.
  
  
  // DAC Configuration
  analogWrite (DAC0, 0); // Enable DAC0
  analogWrite (DAC1, 0); // Enable DAC0
  
  
 // set pin2 as an input and enable the internal pull-up resistor
 // pinMode (LED, OUTPUT);
 // pinMode (TOGGLE, INPUT_PULLUP);
 // attachInterrupt (TOGGLE, switch_handler, CHANGE);
 // pinMode (FOOTSWITCH, INPUT);
  }
 
void loop ()
{
  // Read the ADCs
  while ((ADC -> ADC_ISR & 0x1CC3)! = 0x1CC3); // expects the conversion of ADC 0, 1, 6, 7, 8, 9, 10 to complete.
  in_ADC0 = ADC -> ADC_CDR [7] // read data from ADC0
  in_ADC1 = ADC -> ADC_CDR [6] // read data from ADC1
  POT0 = ADC -> ADC_CDR [10] // read data from ADC8
  POT1 = ADC -> ADC_CDR [11] // read data from ADC9
  POT2 = ADC -> ADC_CDR [12] // read data from ADC10
  POT3 = ADC -> ADC_CDR [0]; // read data from ADC7
  POT4 = ADC -> ADC_CDR [1]; // read data from ADC6
  }
 
void TC4_Handler ()
{
  // We need to get the status to clear it and allow the interrupt to fire again
  TC_GetStatus (TC1, 1);
  
  if (effect_1 == HIGH) // EFFECT 1: Symmetric distortion
  {
   // digitalWrite (LED, LOW);
    upper_threshold = map (POT0, 0, 4095, 4095,! POT0);
    lower_threshold = map (POT0, 0, 4095, 0000, POT0);
    
  // upper_threshold0 =! upper_threshold;
  // lower_threshold0 =! lower_threshold;
 
  if (in_ADC0> = upper_threshold) in_ADC0 = upper_threshold;
  else if (in_ADC0 <lower_threshold) in_ADC0 = lower_threshold;
  // if (in_ADC1> = upper_threshold) in_ADC1 = upper_threshold;
  // else if (in_ADC1 <lower_threshold) in_ADC1 = lower_threshold;
  
  // adjust the volume with POT4 with constant intensity
  out_DAC0 = map (in_ADC0, lower_threshold, upper_threshold, 1, POT4);
  // out_DAC1 = map (in_ADC1, lower_threshold, upper_threshold, 1, POT4);
  
  // Record the DACs
  dacc_set_channel_selection (DACC_INTERFACE, 0) // selects DAC channel 0
  dacc_write_conversion_data (DACC_INTERFACE, out_DAC0) // write to DAC 0
  // dacc_set_channel_selection (DACC_INTERFACE, 1) // select DAC channel 1
  // dacc_write_conversion_data (DACC_INTERFACE, out_DAC1); // writes in DAC 1
  }
  
  if (effect_2 == HIGH) // EFFECT 2: Clean.
  {
    // Addvolume feature with POT4
    out_DAC0 = map (in_ADC0,0,4095,1, POT4);
    // out_DAC1 = map (in_ADC1,0,4095,1, POT4);
    
    // Write the DACs
    dacc_set_channel_selection (DACC_INTERFACE, 0); // select DAC channel 0
    dacc_write_conversion_data (DACC_INTERFACE, out_DAC0); // writes in DAC 0
    // dacc_set_channel_selection (DACC_INTERFACE, 1); // select DAC channel 1
    // dacc_write_conversion_data (DACC_INTERFACE, out_DAC1); // writes in DAC 1
    }
    
    if (effect_3 == HIGH) // EFFECT 3: Delay.
  {
    // digitalWrite (LED, LOW);
    
  // Store current readings
  // sDelayBuffer0 [DelayCounter] = in_ADC0;
  sDelayBuffer1 [DelayCounter] = in_ADC1;
  
  // Set the delay depth based on the position of pot2.
  Delay_Depth = map (POT2 >> 2.0,1023,1, MAX_DELAY);
  
  // Increse / reset delay counter.
  DelayCounter ++;
  if (DelayCounter> = Delay_Depth) DelayCounter = 0;
  // out_DAC0 = ((sDelayBuffer0 [DelayCounter]));
  out_DAC1 = ((sDelayBuffer1 [DelayCounter]));
  
  // Add volume feature
  // out_DAC0 = map (out_DAC0,0,4095,1, POT3);
  out_DAC1 = map (out_DAC1,0,4095,1, POT3);
  
  // Write the DACs
  // dacc_set_channel_selection (DACC_INTERFACE, 0); // select DAC channel 0
  // dacc_write_conversion_data (DACC_INTERFACE, out_DAC0); // writes in the DAC
  dacc_set_channel_selection (DACC_INTERFACE, 1); // select DAC channel 1
  dacc_write_conversion_data (DACC_INTERFACE, out_DAC1); // writes in DAC 0
  
  // Clear status allowing the interrupt to be triggered again.
  TC_GetStatus (TC1, 1);
  }
  
  // void switch_handler ()
  
  // delayMicroseconds (100000); // debouncing protection
  // if (toggle_value! = digitalRead (TOGGLE)) ++ effect;
  // delayMicroseconds (100000); // debouncing protection
    // toggle_value = digitalRead (TOGGLE);
    // if (effect == 1) effect = 0;
    // Delay_Depth = 300; // resets the variable.
    
    if (effect_4 == HIGH) // EFFECT 4: Tremolo.
    {
      // Store current readings in ECHO mode
      DelayBuffer_A [DelayCounter_A] = (in_ADC0 + (DelayBuffer_A [DelayCounter_A])) >> 1;
      DelayBuffer_B [DelayCounter_B] = (in_ADC1 + (DelayBuffer_B [DelayCounter_B])) >> 1;
      
      // Set the delay depth based on position POT2 and POT2.
      Delay_Depth_A = map (POT2 >> 3,0,512,1, MAX_DELAY_A);
      Delay_Depth_B = map (POT2 >> 3,0,512,1, MAX_DELAY_B);
      
      // Increse / reset delay counter.
      DelayCounter_A ++;
      DelayCounter_B ++;
      if (DelayCounter_A> = Delay_Depth_A) DelayCounter_A = 0;
      if (DelayCounter_B> = Delay_Depth_B) DelayCounter_B = 0;
      
      // Calculate the output as the sum of DelayBuffer_A + DelayBuffer_B
      // out_DAC0 = (DelayBuffer_A [DelayCounter_A]);
      out_DAC1 = (DelayBuffer_B [DelayCounter_B]);
      
      // Add volume feature based on pot3 position.
      // out_DAC0 = map (out_DAC0,0,4095,1, POT3);
      out_DAC1 = map (out_DAC1,0,4095,1, POT3);
      
      // Write the DACs
      // dacc_set_channel_selection (DACC_INTERFACE, 0); // select DAC channel 0
      // dacc_write_conversion_data (DACC_INTERFACE, out_DAC0); // writes in DAC 0
      dacc_set_channel_selection (DACC_INTERFACE, 1); // select DAC channel 1
      dacc_write_conversion_data (DACC_INTERFACE, out_DAC1); // writes in DAC 1
      }}