Запрос на помощь в сжатии кода и сохранении памяти

Я строю окончательный проект для класса, который включает в себя воспроизведение аудиофайла волнового щита каждый раз, когда я сканирую amiibo с помощью RFID-сканера. Я довольно неопытный программист, поэтому я не очень хорошо знаком с тем, как лучше всего уменьшить использование DRAM. Таким образом, при попытке выполнить последнюю итерацию кода я получил следующую ошибку:

Глобальные переменные используют 2801 байт (136%) динамической памяти, оставляя -753 байта для локальных переменных. Максимум-2048 байт.

Вот мой код:

////// WAVE SHIELD HEADERS //////
#include <FatReader.h>
#include <SdReader.h>
#include <avr/pgmspace.h>
#include "WaveUtil.h"
#include "WaveHC.h"
/////////////////////////////////

/////// LCD HEADERS /////////////
#include <Wire.h> 
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,16,2);  // set the LCD address to 0x27 for a 16 chars and 2 line display

//////////////////////////////////////////

////////// RFID HEADERS /////////////////
#include <SPI.h>
#include <Adafruit_PN532.h>

#define PN532_IRQ   (6)
#define PN532_RESET (3)  // Not connected by default on the NFC Shield

Adafruit_PN532 nfc(PN532_IRQ, PN532_RESET);

/////// various declarations /////////
uint8_t GLOBALUID[7];


//////////////////////////// WAVE SHIELD PORTION OF CODE ///////////////////////////////////


SdReader card;    // This object holds the information for the card
FatVolume vol;    // This holds the information for the partition on the card
FatReader root;   // This holds the information for the filesystem on the card
FatReader f;      // This holds the information for the file we're play

WaveHC wave;      // This is the only wave (audio) object, since we will only play one at a time

#define DEBOUNCE 100  // button debouncer

// this handy function will return the number of bytes currently free in RAM, great for debugging!   
int freeRam(void)
{
  extern int  __bss_end; 
  extern int  *__brkval; 
  int free_memory; 
  if((int)__brkval == 0) {
    free_memory = ((int)&free_memory) - ((int)&__bss_end); 
  }
  else {
    free_memory = ((int)&free_memory) - ((int)__brkval); 
  }
  return free_memory; 
} 

void sdErrorCheck(void)
{
  if (!card.errorCode()) return;
  putstring("\n\rSD I/O error: ");
  Serial.print(card.errorCode(), HEX);
  putstring(", ");
  Serial.println(card.errorData(), HEX);
  while(1);
}

/////// MAIN SETUP /////////

void setup() {
  // set up serial port
  Serial.begin(115200);
  
  // Set the output pins for the DAC control in the wave shield.
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);

  // Set button outputs
  pinMode(A0, INPUT);
  pinMode(A1, INPUT);
  
  // Set random seed for picking amiibo
  randomSeed(analogRead(A2));

  // initialize lcd
  lcd.init();
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0,0);
  
   if (!card.init()) {
    putstring_nl("Card init. failed!");
    sdErrorCheck();
    while(1);
  }
  
  // enable optimize read - some cards may timeout. Disable if you're having problems
  card.partialBlockRead(true);
 
// look for a FAT partition
  uint8_t part;
  for (part = 0; part < 5; part++) {
    if (vol.init(card, part)) 
      break;
  }
  if (part == 5) {
    putstring_nl("No valid FAT partition!");
    sdErrorCheck();
    while(1);
  }
  
  // tell the user about what was found
  putstring("Using partition ");
  Serial.print(part, DEC);
  putstring(", type is FAT");
  Serial.println(vol.fatType(),DEC);     // FAT16 or FAT32?
  
  // Try to open the root directory
  if (!root.openRoot(vol)) {
    putstring_nl("Can't open root dir!");
    while(1);
  }
}
//////////// END OF WAVE SHIELD ///////////////


////////////// FUNCTION FOR SELECTING AUDIO FILES ////////////
void playSoundClip(){

  char charUID[7];

  for(int i = 0; i < 7; i++)
    charUID[i] = GLOBALUID[i];

  Serial.println();

/*
      {"Mario",                   { 4, 79, 119, 42, 55, 60, 128 },"MARIO"},     //0
      {"Meta Knight",             { 4, 243, 209, 58, 117, 76, 128},"MK"},       //1
      {"Inkling",                 { 4, 84, 47, 218, 87, 73, 128 },"INK"},       //2
      {"Donkey Kong",             { 4, 244, 122, 98, 249, 61, 128 },"DK"},      //3
      {"Lucas",                   { 4, 7, 52, 202, 178, 73, 129 },"LUCAS"},     //4
      {"Duck Hunt",               { 4, 40, 173, 146, 84, 73, 128 },"DUCKH"},    //5
      {"Ocarina of Time Link",    { 4 163 57 114 221 76 128 },"OOTL"},          //6
      {"Breath of The Wild Link", ( 4 133 61 74 120 76 128 },"BOTWL"},          //7
      {"8-bit Link",              { 4 192 150 130 221 76 128 },"8BITL"},        //8
      {"Toon Link",               { 4, 89, 88, 226, 161, 62, 128 },"TOONL"},    //9      
      {"Mr. Game and Watch",      { 4, 134, 32, 154, 85, 73, 128 },"GANDW"},    //10
      {"Falco",                   { 4, 23, 139, 178, 17, 74, 129 },"FALCO"},    //11
      {"King Dedede",             { 4, 108, 188, 242, 232, 73, 128 },"DEDEDE"}, //12
      {"Mewtwo",                  { 4, 241, 126, 202, 87, 73, 128 },"MEWTWO"},  //13
      {"Captain Falcon",          { 4, 11, 204, 178, 124, 72, 129 },"CAPF"},    //14
      {"ROB",                     { 4, 40, 208, 50, 3, 73, 128 },"ROB"},        //15
      {"PAC-MAN",                 { 4, 45, 26, 2, 114, 64, 129 },"PACMAN"},     //16
      {"Cloud",                   { 4, 107, 128, 26, 114, 64, 128 },"CLOUD"},   //17
      {"Ness",                    { 4, 107, 128, 26, 114, 64, 128 },"NESS"},    //18
      {"Ryu",                     { 4, 109, 252, 234, 33, 75, 128 },"RYU"}      //19
*/

  uint8_t amiiboNo = 0;
  
  if(strcmp(charUID,"479119425560128"))
    amiiboNo = 0; //Mario
  else if(strcmp(charUID,"42432095811776128"))
    amiiboNo = 1; //Meta Knight
  else if(strcmp(charUID,"484472188773128"))
    amiiboNo = 2; //Inkling
  else if(strcmp(charUID,"42441229824961128"))
    amiiboNo = 3;// Donkey Kong
  else if(strcmp(charUID,"475220217873129"))
    amiiboNo = 4;// Lucas
  else if(strcmp(charUID,"4401731468473128"))
    amiiboNo = 5;// Duck Hunt
  else if(strcmp(charUID,"41635711422176128"))
    amiiboNo = 6;// Ocarina of Time Link
  else if(strcmp(charUID,"4133617412076128"))
    amiiboNo = 7;// Breath of The Wild Link
  else if(strcmp(charUID,"419215013022176128"))
    amiiboNo = 8;// 8-bit link
  else if(strcmp(charUID,"4898822616162128"))
    amiiboNo = 9;// toon link
  else if(strcmp(charUID,"4134321548573128"))
    amiiboNo = 10;// Mr. Game and Watch
  else if(strcmp(charUID,"4231391781774129"))
    amiiboNo = 11;// Falco
  else if(strcmp(charUID,"410818824223273128"))
    amiiboNo = 12;// king dedede
  else if(strcmp(charUID,"42411262028773128"))
    amiiboNo = 13;// Mewtwo
  else if(strcmp(charUID,"41120417812472129"))
    amiiboNo = 14;// Captain Falcon
  else if(strcmp(charUID,"44020850373128"))
    amiiboNo = 15;// ROB
  else if(strcmp(charUID,"44526211464129"))
    amiiboNo = 16;// Pacman
  else if(strcmp(charUID,"424913721823376128"))
    amiiboNo = 17;// Cloud
  else if(strcmp(charUID,"41071282611464128"))
    amiiboNo = 18;// Ness
  else if(strcmp(charUID,"41092522343375128"))
    amiiboNo = 19;// Ryu

  Serial.println(amiiboNo);
  
  uint8_t clipNo = random(3);
  
  switch(amiiboNo){
    case 0:
      if(clipNo == 0)
        playComplete("MARIO01.WAV");
      else if(clipNo == 1)
        playComplete("MARIO02.WAV");
      else if(clipNo == 2)
        playComplete("MARIO03.WAV");
      break;
    case 1:
      if(clipNo == 0)
        playComplete("MK01.WAV");
      else if(clipNo == 1)
        playComplete("MK02.WAV");
      else if(clipNo == 2)
        playComplete("MK03.WAV");
      break;
    case 2:
      if(clipNo == 0)
        playComplete("INK01.WAV");
      else if(clipNo == 1)
        playComplete("INK02.WAV");
      else if(clipNo == 2)
        playComplete("INK03.WAV");
       break;
    case 3:
      if(clipNo == 0)
        playComplete("DK01.WAV");
      else if(clipNo == 1)
        playComplete("DK02.WAV");
      else if(clipNo == 2)
        playComplete("DK03.WAV");
       break;
    case 4:
      if(clipNo == 0)
        playComplete("LUCAS01.WAV");
      else if(clipNo == 1)
        playComplete("LUCAS02.WAV");
      else if(clipNo == 2)
        playComplete("LUCAS03.WAV");
       break;
    case 5:
      if(clipNo == 0)
        playComplete("DUCKH01.WAV");
      else if(clipNo == 1)
        playComplete("DUCKH02.WAV");
      else if(clipNo == 2)
        playComplete("DUCKH03.WAV");
       break;
    case 6:
      if(clipNo == 0)
        playComplete("OOT01.WAV");
      else if(clipNo == 1)
        playComplete("OOT02.WAV");
      else if(clipNo == 2)
        playComplete("OOT03.WAV");
       break;
    case 7:
      if(clipNo == 0)
        playComplete("BOTWL01.WAV");
      else if(clipNo == 1)
        playComplete("BOTWL02.WAV");
      else if(clipNo == 2)
        playComplete("BOTWL03.WAV");
       break;
    case 8:
      if(clipNo == 0)
        playComplete("8BITL01.WAV");
      else if(clipNo == 1)
        playComplete("8BITL02.WAV");
      else if(clipNo == 2)
        playComplete("8BITL03.WAV");
       break;
    case 9:
      if(clipNo == 0)
        playComplete("TOONL01.WAV");
      else if(clipNo == 1)
        playComplete("TOONL02.WAV");
      else if(clipNo == 2)
        playComplete("TOONL03.WAV");
       break;
    case 10:
      if(clipNo == 0)
        playComplete("GANDW01.WAV");
      else if(clipNo == 1)
        playComplete("GANDW02.WAV");
      else if(clipNo == 2)
        playComplete("GANDW03.WAV");
       break;
    case 11:
      if(clipNo == 0)
        playComplete("FALCO01.WAV");
      else if(clipNo == 1)
        playComplete("FALCO02.WAV");
      else if(clipNo == 2)
        playComplete("FALCO03.WAV");
       break;
    case 12:
      if(clipNo == 0)
        playComplete("DEDEDE01.WAV");
      else if(clipNo == 1)
        playComplete("DEDEDE02.WAV");
      else if(clipNo == 2)
        playComplete("DEDEDE03.WAV");
       break;
    case 13:
      if(clipNo == 0)
        playComplete("MEWTWO01.WAV");
      else if(clipNo == 1)
        playComplete("MEWTWO02.WAV");
      else if(clipNo == 2)
        playComplete("MEWTWO03.WAV");
       break;
    case 14:
      if(clipNo == 0)
        playComplete("CAPF01.WAV");
      else if(clipNo == 1)
        playComplete("CAPF02.WAV");
      else if(clipNo == 2)
        playComplete("CAPF03.WAV");
       break;
    case 15:
      if(clipNo == 0)
        playComplete("ROB01.WAV");
      else if(clipNo == 1)
        playComplete("ROB02.WAV");
      else if(clipNo == 2)
        playComplete("ROB03.WAV");
       break;
    case 16:
      if(clipNo == 0)
        playComplete("PACMAN01.WAV");
      else if(clipNo == 1)
        playComplete("PACMAN02.WAV");
      else if(clipNo == 2)
        playComplete("PACMAN03.WAV");
       break;
    case 17:
      if(clipNo == 0)
        playComplete("CLOUD01.WAV");
      else if(clipNo == 1)
        playComplete("CLOUD02.WAV");
      else if(clipNo == 2)
        playComplete("CLOUD03.WAV");
       break;
    case 18:
      if(clipNo == 0)
        playComplete("NESS01.WAV");
      else if(clipNo == 1)
        playComplete("NESS02.WAV");
      else if(clipNo == 2)
        playComplete("NESS03.WAV");
       break;
    case 19:
      if(clipNo == 0)
        playComplete("RYU01.WAV");
      else if(clipNo == 1)
        playComplete("RYU02.WAV");
      else if(clipNo == 2)
        playComplete("RYU03.WAV");
       break;
       
    }
}

//////// MAIN LOOP /////////
void loop() {

      lcd.print("Scan an");
      lcd.setCursor(0,1);
      lcd.print("amiibo!");
      delay(3000);
    
    uint8_t * ID{};
        
    waitForRFID();
    
    playSoundClip();
    
  
}


//////////////// MORE WAVE SHIELD ///////////////////////

// Plays a full file from beginning to end with no pause.
void playComplete(char *name) {
  // call our helper to find and play this name
  playfile(name);
  while (wave.isplaying) {
  // do nothing while its playing
  }
  // now its done playing
}

void playfile(char *name) {
  // see if the wave object is currently doing something
  if (wave.isplaying) {// already playing something, so stop it!
    wave.stop(); // stop it
  }
  // look in the root directory and open the file
  if (!f.open(root, name)) {
    putstring("Couldn't open file "); Serial.println(name); return;
  }
  // OK read the file and turn it into a wave object
  if (!wave.create(f)) {
    putstring_nl("Not a valid WAV"); return;
  }
  
  // ok time to play! start playback
  wave.play();
}

/////////////// END OF WAVE SHIELD //////////////////////

//////////////// RFID FUNCTION /////////////////////////
uint8_t* waitForRFID(){
    nfc.SAMConfig();
  
  Serial.println("Waiting for an amiibo ...");

  uint8_t success;
  uint8_t uid[] = { 0, 0, 0, 0, 0, 0, 0 };
  uint8_t uidLength;
  uint8_t testuid[7];
  while(true){
    if (nfc.readPassiveTargetID(PN532_MIFARE_ISO14443A, uid, &uidLength)){

      Serial.print("Hex UID: ");
      nfc.PrintHex(uid, uidLength);
      Serial.print("Octal UID: { ");
      for(int i = 0; i < uidLength; i++){
        Serial.print(uid[i]);
        GLOBALUID[i] = uid[i];
        if (i != uidLength - 1)
          Serial.print(", ");
      }
      Serial.println(" }");

      Serial.print("GLOBALUID: ");
      for(int i = 0; i < 7; i++)
        Serial.print(GLOBALUID[i]);
        
      Serial.println();
      Serial.println();
    }
    return testuid;
  }
  
}

//////////////// END OF RFID FUNCTION /////////////////

Мое первое предположение о том, что может занимать больше всего памяти, - это оператор switch. Когда я раскомментирую его, использование памяти подскочит с 90% до более чем 130%. Я пробовал другие способы заставить этот код работать, например конкатенацию текста, но это единственный способ, который, казалось, работал надежно, пока у меня не закончилась память.

Я также использую множество библиотек, чтобы помочь использовать щиты и ЖК-дисплей, которые я прикрепил к Uno. Я не мог избавиться от этих библиотек, не поставив под угрозу проект.

Кроме этого, я не знаю, что делать. Если у кого-то есть какие-либо предложения по сжатию кода, я был бы очень признателен за любой совет, который вы можете предложить.

Спасибо.