Lawrence Quizon / Mbed OS play_wav

For MAX323630FTHR: Plays a WAV file in the SD card. Interfaced through serial port using puTTY or powershell.

Dependencies:   USBMSD_BD SDFileSystem max32630fthr USBDevice

main.cpp@0:12c56a256ee1, 2019-07-16 (annotated)

Committer:
Lugs
Date:
Tue Jul 16 08:11:48 2019 +0000
Revision:
0:12c56a256ee1
Child:
1:7884bc0fb012
still caching version

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Lugs 0:12c56a256ee1 1 #include "mbed.h"
Lugs 0:12c56a256ee1 2 #include "max32630fthr.h"
Lugs 0:12c56a256ee1 3 #include "USBSerial.h"
Lugs 0:12c56a256ee1 4 #include "stdio.h"
Lugs 0:12c56a256ee1 5 #include "SDFileSystem.h"
Lugs 0:12c56a256ee1 6
Lugs 0:12c56a256ee1 7 //still needs BITS PER SAMPLE PARSING.
Lugs 0:12c56a256ee1 8 //do this like so: PWM.write(WavValue/2^BPS)
Lugs 0:12c56a256ee1 9
Lugs 0:12c56a256ee1 10 #define BUFFER_SIZE 1024
Lugs 0:12c56a256ee1 11 #define HALF_BUFFER 512
Lugs 0:12c56a256ee1 12
Lugs 0:12c56a256ee1 13 DigitalOut rLED(LED1);
Lugs 0:12c56a256ee1 14 DigitalOut gLED(LED2);
Lugs 0:12c56a256ee1 15 DigitalOut bLED(LED3);
Lugs 0:12c56a256ee1 16
Lugs 0:12c56a256ee1 17 DigitalIn Button(P2_3);
Lugs 0:12c56a256ee1 18
Lugs 0:12c56a256ee1 19 MAX32630FTHR pegasus(MAX32630FTHR::VIO_3V3);
Lugs 0:12c56a256ee1 20 PwmOut PWM(P5_6);
Lugs 0:12c56a256ee1 21 AnalogIn POT(AIN_0);
Lugs 0:12c56a256ee1 22 volatile int bufferPOS = 0;
Lugs 0:12c56a256ee1 23
Lugs 0:12c56a256ee1 24 Serial daplink(P2_1,P2_0);
Lugs 0:12c56a256ee1 25 USBSerial microUSB;
Lugs 0:12c56a256ee1 26 SDFileSystem sd(P0_5, P0_6, P0_4, P0_7, "sd");
Lugs 0:12c56a256ee1 27
Lugs 0:12c56a256ee1 28 int audioDataBuffer[BUFFER_SIZE];
Lugs 0:12c56a256ee1 29
Lugs 0:12c56a256ee1 30 struct WavFile
Lugs 0:12c56a256ee1 31 {
Lugs 0:12c56a256ee1 32 long int size;
Lugs 0:12c56a256ee1 33 int channels;
Lugs 0:12c56a256ee1 34 int sampleRate;
Lugs 0:12c56a256ee1 35 int bitsPerSample;
Lugs 0:12c56a256ee1 36 };
Lugs 0:12c56a256ee1 37
Lugs 0:12c56a256ee1 38 WavFile Track;
Lugs 0:12c56a256ee1 39
Lugs 0:12c56a256ee1 40 void placeNewSample(void)
Lugs 0:12c56a256ee1 41 {
Lugs 0:12c56a256ee1 42 //POT.read(); //COMMENTED OUT FOR TESTING
Lugs 0:12c56a256ee1 43 PWM = (float) audioDataBuffer[bufferPOS]/Track.bitsPerSample; //multiply by POT value for volume.
Lugs 0:12c56a256ee1 44 bufferPOS = (bufferPOS+1) & 0x07F;
Lugs 0:12c56a256ee1 45 }
Lugs 0:12c56a256ee1 46
Lugs 0:12c56a256ee1 47
Lugs 0:12c56a256ee1 48 int main()
Lugs 0:12c56a256ee1 49 {
Lugs 0:12c56a256ee1 50
Lugs 0:12c56a256ee1 51 daplink.printf("\f---DAPLINK SERIAL PORT---\r\n\r\nWAV PLAYER VER 2\r\n\r\n");
Lugs 0:12c56a256ee1 52 microUSB.printf("micro USB serial port\r\n");
Lugs 0:12c56a256ee1 53 rLED = LED_ON;
Lugs 0:12c56a256ee1 54 wait_ms(500);
Lugs 0:12c56a256ee1 55 rLED = LED_OFF;
Lugs 0:12c56a256ee1 56 gLED = LED_ON;
Lugs 0:12c56a256ee1 57 wait_ms(500);
Lugs 0:12c56a256ee1 58 bLED = LED_ON;
Lugs 0:12c56a256ee1 59 gLED = LED_OFF;
Lugs 0:12c56a256ee1 60
Lugs 0:12c56a256ee1 61 Ticker SampleTime;
Lugs 0:12c56a256ee1 62
Lugs 0:12c56a256ee1 63 FILE *audio = fopen("/sd/1.wav","r");
Lugs 0:12c56a256ee1 64
Lugs 0:12c56a256ee1 65 if(!audio)
Lugs 0:12c56a256ee1 66 {
Lugs 0:12c56a256ee1 67 printf("Failed to open file. [Exit]\r\n");
Lugs 0:12c56a256ee1 68 return 0;
Lugs 0:12c56a256ee1 69 }
Lugs 0:12c56a256ee1 70
Lugs 0:12c56a256ee1 71 printf("File opened.\r\n\r\n");
Lugs 0:12c56a256ee1 72
Lugs 0:12c56a256ee1 73 //find file size
Lugs 0:12c56a256ee1 74 fseek(audio,0L,SEEK_END);
Lugs 0:12c56a256ee1 75 Track.size = ftell(audio);
Lugs 0:12c56a256ee1 76
Lugs 0:12c56a256ee1 77 printf("File Size:%li \r\n",Track.size);
Lugs 0:12c56a256ee1 78
Lugs 0:12c56a256ee1 79 //read sample rate of wav file
Lugs 0:12c56a256ee1 80 fseek(audio,22,SEEK_SET);
Lugs 0:12c56a256ee1 81 fread(audioDataBuffer, 4, 1,audio);
Lugs 0:12c56a256ee1 82
Lugs 0:12c56a256ee1 83 printf("Raw Sample Rate Data: %i\r\n",audioDataBuffer[4]);
Lugs 0:12c56a256ee1 84
Lugs 0:12c56a256ee1 85 Track.channels = audioDataBuffer[0];
Lugs 0:12c56a256ee1 86 Track.sampleRate =(audioDataBuffer[3] << 8) + audioDataBuffer[2]; //needs to be done due to little-endian encoding of wave file headers
Lugs 0:12c56a256ee1 87
Lugs 0:12c56a256ee1 88 printf("Sample Rate: %i\r\n",Track.sampleRate);
Lugs 0:12c56a256ee1 89 printf("%i channels \r\n",Track.channels);
Lugs 0:12c56a256ee1 90
Lugs 0:12c56a256ee1 91 //read bits per sample
Lugs 0:12c56a256ee1 92 fseek(audio,34,SEEK_SET);
Lugs 0:12c56a256ee1 93 fread(audioDataBuffer, 2, 1,audio);
Lugs 0:12c56a256ee1 94 Track.bitsPerSample = (audioDataBuffer[1] << 8) + audioDataBuffer[0];
Lugs 0:12c56a256ee1 95
Lugs 0:12c56a256ee1 96 printf("Bits Per Sample: %i\r\n",Track.bitsPerSample);
Lugs 0:12c56a256ee1 97
Lugs 0:12c56a256ee1 98 int flag;
Lugs 0:12c56a256ee1 99 //find start of actual audio
Lugs 0:12c56a256ee1 100 fseek(audio,44,SEEK_SET);
Lugs 0:12c56a256ee1 101 int bytecount;
Lugs 0:12c56a256ee1 102 bytecount = Track.size;
Lugs 0:12c56a256ee1 103
Lugs 0:12c56a256ee1 104 printf("Size: %i bytes\r\nPlay time: %f minutes",Track.size,(float)((Track.size-44)*8)/Track.bitsPerSample);
Lugs 0:12c56a256ee1 105
Lugs 0:12c56a256ee1 106 //initialize PWM to 1us period [1MHz]
Lugs 0:12c56a256ee1 107 PWM.period_us(1);
Lugs 0:12c56a256ee1 108 SampleTime.attach(&placeNewSample,1/(Track.sampleRate));
Lugs 0:12c56a256ee1 109 //microcontroller may not be strong enough to call fread after attaching a 44.1kHz wav file.
Lugs 0:12c56a256ee1 110
Lugs 0:12c56a256ee1 111 printf("\r\nTicker attached.\r\nRunning Loop...\r\n\r\n");
Lugs 0:12c56a256ee1 112
Lugs 0:12c56a256ee1 113 //take the first block of audio data into the buffer (buffer size is two blocks)
Lugs 0:12c56a256ee1 114 fread(audioDataBuffer,HALF_BUFFER,1,audio);
Lugs 0:12c56a256ee1 115
Lugs 0:12c56a256ee1 116 int g=0;
Lugs 0:12c56a256ee1 117
Lugs 0:12c56a256ee1 118 while(ftell(audio) != Track.size)
Lugs 0:12c56a256ee1 119 {
Lugs 0:12c56a256ee1 120 printf("Loop %i\f",g++);
Lugs 0:12c56a256ee1 121 if(bufferPOS < HALF_BUFFER && flag == 0)
Lugs 0:12c56a256ee1 122 {
Lugs 0:12c56a256ee1 123 fread(audioDataBuffer + HALF_BUFFER,HALF_BUFFER,1,audio);
Lugs 0:12c56a256ee1 124 bytecount -= HALF_BUFFER;
Lugs 0:12c56a256ee1 125 flag = 1;
Lugs 0:12c56a256ee1 126 }
Lugs 0:12c56a256ee1 127 else if(bufferPOS >= HALF_BUFFER && flag == 1)
Lugs 0:12c56a256ee1 128 {
Lugs 0:12c56a256ee1 129 fread(audioDataBuffer,HALF_BUFFER,1,audio);
Lugs 0:12c56a256ee1 130 bytecount -= HALF_BUFFER;
Lugs 0:12c56a256ee1 131 flag = 0;
Lugs 0:12c56a256ee1 132 }
Lugs 0:12c56a256ee1 133 }
Lugs 0:12c56a256ee1 134 };
Lugs 0:12c56a256ee1 135