main.cpp

00001 #include "mbed.h"
00002 #include "SDFileSystem.h"
00003 #include "wave_player.h"
00004 #include "TextLCD.h"
00005 #include "PinDetect.h"
00006 #include "Speaker.h"
00007 #include <vector>
00008 #include <string>
00009 
00010 //Set up LEDs
00011 DigitalOut myled(LED1);
00012 DigitalOut myled2(LED2);
00013 DigitalOut myled3(LED3);
00014 DigitalOut myled4(LED4);
00015 
00016 using namespace std;
00017 
00018 SDFileSystem sd(p5, p6, p7, p8, "sd"); //SD card
00019 TextLCD lcd(p9, p10, p11, p12, p13, p14); // rs, e, d4-d7
00020 DigitalIn sdDetect(p17); // Set up a pin for SD Card Detect
00021 
00022 PinDetect pb1(p28); // pb forup shift
00023 PinDetect pb2(p29); // pb fordown shift
00024 PinDetect pb3(p30); // pb for pause
00025 PinDetect pb4(p27); // pb for volume or play
00026 
00027 
00028 AnalogOut DACout(p18); //set up speaker
00029 wave_player waver(&DACout); //set up wave player library
00030 int pos = 0; // index of the song
00031 int vol = 0; // volume controller
00032  
00033 bool playing = false; //variable for pause/play since we only have 1 pb for that
00034 vector<string> filenames; //filenames are stored in a vector string
00035 void read_file_names(char *dir) // function that reads in file names from sd cards
00036 {
00037     DIR *dp;
00038     struct dirent *dirp;
00039     dp = opendir(dir);
00040     //read all directory and file names in current directory into filename vector
00041     while((dirp = readdir(dp)) != NULL) {
00042         filenames.push_back(string(dirp->d_name));
00043     }
00044 }
00045 //interrupt handler for pb1 
00046 void pb1_hit_callback (void)
00047 {
00048     // it checks for the total number of songs in the sd card..then increments the index until it reaches the last one, then resets to 0
00049     int l = filenames.size();
00050     if (pos < (l-1)) {
00051         pos++;
00052     } else if (pos == (l-1)) {
00053         pos = 0;
00054     }
00055     string songname = filenames[pos];
00056     unsigned index = songname.find(".wav");
00057     songname = songname.substr(0,index);
00058     lcd.cls();
00059     lcd.printf(songname.c_str()); //it clears screen and then sets the new index song in the lcd display
00060 }
00061 //interrupt handler for pb2
00062 void pb2_hit_callback (void)
00063 {
00064     //does opposite of pb1..moves the index down..from 2nd song to 1st song via changing the index number and then calling in the vector
00065     int l = filenames.size();
00066     if (pos > 0) {
00067         pos--;
00068     } else if (pos == 0 ) {
00069         pos = l-1;
00070     }
00071     string songname = filenames[pos];
00072     unsigned index = songname.find(".wav");
00073     songname = songname.substr(0,index);
00074     lcd.cls();
00075     lcd.printf(songname.c_str());
00076 }
00077 //interrupt handler for 3rd pushbutton
00078 void pb3_hit_callback (void)
00079 {
00080     //this interrupt handler changes the play to pause mode or vice versa
00081     //this is done using the boolean playing
00082     if (playing == false) {
00083         playing = true; 
00084     } else if (playing == true) {
00085         lcd.cls();
00086         playing = false; 
00087         string songname = filenames[pos];
00088         unsigned index = songname.find(".wav");
00089         songname = songname.substr(0,index);
00090         lcd.printf(songname.c_str());
00091     }
00092 }
00093 //interrupt handler for pb4
00094 void pb4_hit_callback (void){
00095     // this pb changes the volume by lowering the volume until it reaches 0. then it resets to the max volume
00096     // the volume range has been divided into 16 possible ranges. and hence, it toggles through those 16 values
00097     // this only changes the variable vol, which is then used in the wave player file to actually adjust the volume
00098     vol = (vol+1) % 16;
00099 }
00100 
00101 int main()
00102 {
00103     sdDetect.mode(PullUp);
00104      wait(.1);
00105      //wait after pulling up the sd card, 
00106     // read file names into vector of strings
00107     pb1.mode(PullUp);
00108     pb2.mode(PullUp);
00109     pb3.mode(PullUp);
00110     pb4.mode(PullUp);
00111     // Delay for initial pullup to take effect
00112     wait(.01);
00113     // Setup Interrupt callback functions for a pb hit
00114     pb1.attach_deasserted(&pb1_hit_callback);
00115     pb2.attach_deasserted(&pb2_hit_callback);
00116     pb3.attach_deasserted(&pb3_hit_callback);
00117     pb4.attach_deasserted(&pb4_hit_callback);
00118     // Start sampling pb inputs using interrupts
00119     pb1.setSampleFrequency();
00120     pb2.setSampleFrequency();
00121     pb3.setSampleFrequency();
00122     pb4.setSampleFrequency();
00123     lcd.cls();
00124     //detects whethere there is a SD card or not.. if not then it prints and informs the user
00125     while(sdDetect ==0) {
00126         lcd.locate(0,0);
00127         lcd.printf("Insert SD Card");
00128         wait(.5);
00129     }    
00130     lcd.cls(); 
00131     wait(.5);
00132     sd.disk_initialize();
00133     read_file_names("/sd/Music");
00134     while(1) {
00135         //while pb3 is low, then we can start playing the song
00136         while(playing == true) { //we have 2 while loops..one while loop makes sure the music player is always on, the other one is for the song
00137             string songname = filenames[pos];
00138             string a = "/sd/Music/";
00139             string fname = a + songname; //retrieves the file name
00140             FILE *wave_file; 
00141             lcd.locate(0,1);
00142             lcd.printf("Now Playing");
00143             wave_file = fopen(fname.c_str(),"r"); //opens the music file
00144             waver.play(wave_file); //plays the music file
00145             fclose(wave_file);
00146         }
00147     }
00148 }