Part 1: Wav Music Player Using Arduino Uno and SD Card

  1/*
  2 * PROJECT: Arduino Mini Karaoke
  3 *      1. wav files and lyrics is located in SD card
  4 *      2. Lyrics will be displayed to 16x2 LCD - not yet
  5 *      3. 
  6 *      
  7 * LINKS:
  8 *  https://github.com/TMRh20/TMRpcm/wiki
  9 *  https://github.com/TMRh20/TMRpcm/wiki/Advanced-Features
 10 *  https://github.com/TMRh20/TMRpcm
 11 *  
 12 *  https://audio.online-convert.com/convert-to-wav
 13 */
 14#include "TMRpcm.h"
 15#include "SD.h"
 16#include "SPI.h"
 17#include "LiquidCrystal.h"
 18
 19TMRpcm audio;
 20LiquidCrystal lcd( 8,  9,  4,  5,  6,  7);
 21File root;
 22
 23#define SD_CS_PIN     2
 24#define SPEAKER_PIN   3
 25#define TMRPCM_VOLUME 4
 26
 27// ####################################
 28// PROTOTHREADING DEFINITIONS HERE:
 29// ####################################
 30unsigned long checkKeypadTaskTimer = 0;
 31const unsigned long checkKeypadTaskInterval = 200;
 32
 33unsigned long playMusicTaskTimer = 0;
 34const unsigned long playMusicTaskInterval = 100;
 35
 36unsigned long updateLCDTaskTimer = 0;
 37const unsigned long updateLCDTaskInterval = 5000;
 38
 39// ####################################
 40// GLOBAL VARIABLES HERE:
 41// ####################################
 42String wavFiles[8];
 43byte wavCnt = 0;
 44byte wavCurrPos = 0;
 45int leftState, rightState, upState, downState, selectState = LOW;
 46long lastDebounceTime = 0;  // the last time the output pin was toggled
 47long debounceDelay = 500;    // the debounce time; increase if the output flickers
 48boolean isPlaying = false;
 49boolean isPaused = false;
 50boolean isPlayNOW = false;
 51boolean isPlayNEXT = false;
 52boolean isPlayPREVIOUS = false;
 53boolean isVolumeUP = false;
 54boolean isVolumeDOWN = false;
 55boolean isBusy = true;
 56int currVolume = TMRPCM_VOLUME;
 57// variables for LCD custom char
 58byte bPLAY[8] = {0x00, 0x00, 0x08, 0x0C, 0x0E, 0x0C, 0x08, 0x00};
 59byte bPAUSE[8] = {0x00, 0x00, 0x1B, 0x1B, 0x1B, 0x1B, 0x1B, 0x00};
 60byte bNEXT[8] = {0x00, 0x00, 0x11, 0x19, 0x1D, 0x19, 0x11, 0x00};
 61byte bPREVIOUS[8] = {0x00, 0x00, 0x11, 0x13, 0x17, 0x13, 0x11, 0x00};
 62byte bUPVOLUME[8] = {0x02, 0x07, 0x02, 0x11, 0x11, 0x1B, 0x0E, 0x04};
 63byte bDOWNVOLUME[8] = {0x00, 0x07, 0x00, 0x11, 0x11, 0x1B, 0x0E, 0x04};
 64
 65// ####################################
 66// PROTOTYPES HERE:
 67// ####################################
 68void getWAVFiles(File dir, int numTabs);
 69int cntChar(String str, char chr);
 70char* strToChar(String str);
 71String parseString(int idSeparator, char separator, String str);
 72int get_key(unsigned int input);
 73
 74// #########################################################
 75//  Put code here for initializations
 76// #########################################################
 77void setup()
 78{
 79  // Initialized LCD
 80  lcd.begin(16, 2);
 81  lcd.createChar(0, bPLAY);
 82  lcd.createChar(1, bPAUSE);
 83  lcd.createChar(2, bNEXT);
 84  lcd.createChar(3, bPREVIOUS);
 85  lcd.createChar(4, bUPVOLUME);
 86  lcd.createChar(5, bDOWNVOLUME);
 87  lcd.setCursor(0,0);
 88  lcd.print(" tech-to-tinker ");
 89
 90  // Initialized TMRPCM
 91  audio.speakerPin = SPEAKER_PIN;
 92  if(!SD.begin(SD_CS_PIN))
 93  {
 94    //Serial.println("SD fail");
 95    return;
 96  }
 97  audio.setVolume(TMRPCM_VOLUME);   // This is the maximum volume 
 98
 99  // Get the wav files available
100  root = SD.open("/");
101  getWAVFiles(root, 0);
102  lcd.setCursor(1,1);
103  lcd.write((byte)1);
104  lcd.setCursor(3,1);
105  lcd.print(wavFiles[wavCurrPos]);
106}
107
108// #########################################################
109//  Put your main code here, to run repeatedly:
110// #########################################################
111void loop() {
112  if(millis() >= checkKeypadTaskTimer + checkKeypadTaskInterval){
113    checkKeypadTaskTimer += checkKeypadTaskInterval;
114    checkKeypad();
115  }
116
117  if(millis() >= playMusicTaskTimer + playMusicTaskInterval){
118    playMusicTaskTimer += playMusicTaskInterval;
119    playMusic();
120  }
121
122  if(millis() >= updateLCDTaskTimer + updateLCDTaskInterval){
123    updateLCDTaskTimer += updateLCDTaskInterval;
124    updateLCD();
125  }
126}
127
128void updateLCD() {
129  if ( audio.isPlaying() ) {
130    if (isPaused) { // currently in paused
131      lcd.setCursor(1,1);
132      lcd.write((byte)1);
133    } else {  // from pause to play
134      lcd.setCursor(1,1);
135      lcd.write((byte)0);
136    }
137  }
138}
139
140void playMusic() {
141  if (isPlayNEXT) {
142    audio.disable();  // this is necessary to prevent overrun
143    lcd.setCursor(1,1);
144    lcd.write((byte)2);
145    isPlayNEXT = false;
146    isPlaying = false;
147    isPlayNOW = true;
148    isPaused = false;
149
150    if ( wavCurrPos < (wavCnt-1) ) {
151      wavCurrPos = wavCurrPos + 1;       // increase music pointer
152    } else {
153      wavCurrPos = 0;     // set music pointer to first
154    }
155  }
156
157  if (isPlayPREVIOUS) {
158    audio.disable();  // this is necessary to prevent overrun
159    lcd.setCursor(1,1);
160    lcd.write((byte)3);
161    isPlayPREVIOUS = false;
162    isPlaying = false;
163    isPlayNOW = true;
164    isPaused = false;
165
166    if ( wavCurrPos == 0 ) {
167      wavCurrPos = (wavCnt-1);  // set pointer to last array
168    } else {
169      wavCurrPos = wavCurrPos - 1;           // decrease pointer
170    }
171  }
172
173  if ( audio.isPlaying() ) {
174
175  } else {
176    if (isPlaying) {
177      audio.disable();  // this is necessary to prevent overrun
178      isPlayNEXT = false;
179      isPlaying = false;
180      isPlayNOW = true;
181      isPaused = false;
182  
183      if ( wavCurrPos < (wavCnt-1) ) {
184        wavCurrPos = wavCurrPos + 1;       // increase music pointer
185      } else {
186        wavCurrPos = 0;     // set music pointer to first
187      }
188    }
189  }
190
191  if (isPlayNOW) {  // Select button pressed
192    isPlayNOW = false;  // disable immediately to prevent playing again 
193    if ( audio.isPlaying() ) {
194      // pause playing
195      audio.pause();  // pauses/unpauses playback
196      if (isPaused) { // currently in paused
197        isPaused = false;
198      } else {  // from pause to play
199        isPaused = true;
200      } 
201    } else {
202      // start playing
203      audio.play( strToChar( wavFiles[wavCurrPos] ) );    //plays a file 
204      lcd.setCursor(3,1);
205      lcd.print("             ");
206      lcd.setCursor(3,1);
207      lcd.print(wavFiles[wavCurrPos]);
208      isPlaying = true;
209    }
210  } 
211  
212  if ( (isVolumeUP) && (currVolume<4) ) {  
213   lcd.setCursor(1,1);  
214   lcd.write((byte)4);  
215   currVolume++;  
216   audio.setVolume(currVolume);  
217   isVolumeUP = false;  
218  }  
219  if ( (isVolumeDOWN) && (currVolume>-1) ) {  
220   lcd.setCursor(1,1);  
221   lcd.write((byte)5);  
222   currVolume--;  
223   audio.setVolume(currVolume);  
224   isVolumeDOWN = false;  
225  }  
226}
227
228int adc_key_val[5] ={50, 200, 400, 600, 800 };  // Original, works after actually reading the analog0
229int NUM_KEYS = 5;
230int adc_key_in;
231int key=-1;  
232
233void checkKeypad() {
234  adc_key_in = analogRead(0);                 // Read the value from the sensor
235  key = get_key(adc_key_in);                  // Convert into key press
236  switch(key) {
237    case 0: // RIGHT
238      isPlayNEXT = true;
239      break;
240    case 1: // UP
241      isVolumeUP = true;
242      break;
243    case 2: // DOWN
244      isVolumeDOWN = true;
245      break;
246    case 3: // LEFT
247      isPlayPREVIOUS = true;
248      break;
249    case 4: // SELECT
250      if (isPlayNOW) {
251        isPlayNOW = false;
252      } else {
253        isPlayNOW = true;
254      }
255      break;
256    default:  // OTHERS
257      break;
258  }
259}
260
261int get_key(unsigned int input) {
262    int k;
263    for (k = 0; k < NUM_KEYS; k++)    // Start counting
264    {
265      //if (input == adc_key_val[k])          // Works, but doesn't allow for deviations
266      if (input < adc_key_val[k])             // should be more reliable as it looks for a range instead of a fixed value.
267      {
268            return k;                         // Breaks the for loop
269      }
270   }
271    if (k >= NUM_KEYS)k = -1;                 // No valid key pressed
272    return k;                                 // So break the loop and look for another keypress
273}
274
275void getWAVFiles(File dir, int numTabs) {
276  byte fileCnt = 0;
277  while (true) {
278    File entry =  dir.openNextFile();
279    if (! entry) {
280      // no more files
281      break;
282    }
283    //Serial.println(entry.name());
284    String ext = parseString(cntChar(entry.name(), '.'), '.', entry.name());
285    if (ext == "WAV") 
286    {
287      wavFiles[wavCnt] = entry.name();
288      wavCnt++;
289    }
290    
291    entry.close();
292  }
293
294  if (wavCnt > 0) {
295    for (byte i = 0; i < wavCnt; i++) {
296      Serial.println(wavFiles[i]);
297    }
298  }   
299  Serial.print("wavCnt :");
300  Serial.println(wavCnt,HEX);
301}
302
303int cntChar(String str, char chr) {
304  int n = 0;
305  for (int i = 0; i < str.length(); i++)
306  {
307    if (str[i] == chr) n++;
308  }
309  return n;
310}
311
312char* strToChar(String str) {
313  int len = str.length() + 1;
314  char* buf = new char[len];
315  strcpy(buf, str.c_str());
316  return buf;
317}
318
319String parseString(int idSeparator, char separator, String str) { // like a split JS
320  String output = "";
321  int separatorCout = 0;
322  for (int i = 0; i < str.length(); i++)
323  {
324    if ((char)str[i] == separator)
325    {
326      separatorCout++;
327    }
328    else
329    {
330      if (separatorCout == idSeparator)
331      {
332        output += (char)str[i];
333      }
334      else if (separatorCout > idSeparator)
335      {
336        break;
337      }
338    }
339  }
340  return output;
341}