Adam Lawrence / Mbed 2 deprecated smartSafe

A safe using the mbed, dc motor, solenoid, and more!

Dependencies:   4DGL-uLCD-SE DebounceIn Motordriver PinDetect SDFileSystem mbed-rtos mbed

wave_player/wave_player.cpp@0:6b5c0ae5acc6, 2016-04-29 (annotated)

Committer:
adamlawrence
Date:
Fri Apr 29 20:01:29 2016 +0000
Revision:
0:6b5c0ae5acc6
initial commit;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
adamlawrence 0:6b5c0ae5acc6 1 //-----------------------------------------------------------------------------
adamlawrence 0:6b5c0ae5acc6 2 // a sample mbed library to play back wave files.
adamlawrence 0:6b5c0ae5acc6 3 //
adamlawrence 0:6b5c0ae5acc6 4 // explanation of wave file format.
adamlawrence 0:6b5c0ae5acc6 5 // https://ccrma.stanford.edu/courses/422/projects/WaveFormat/
adamlawrence 0:6b5c0ae5acc6 6
adamlawrence 0:6b5c0ae5acc6 7 // if VERBOSE is uncommented then the wave player will enter a verbose
adamlawrence 0:6b5c0ae5acc6 8 // mode that displays all data values as it reads them from the file
adamlawrence 0:6b5c0ae5acc6 9 // and writes them to the DAC. Very slow and unusable output on the DAC,
adamlawrence 0:6b5c0ae5acc6 10 // but useful for debugging wave files that don't work.
adamlawrence 0:6b5c0ae5acc6 11 //#define VERBOSE
adamlawrence 0:6b5c0ae5acc6 12
adamlawrence 0:6b5c0ae5acc6 13
adamlawrence 0:6b5c0ae5acc6 14 #include <mbed.h>
adamlawrence 0:6b5c0ae5acc6 15 #include <stdio.h>
adamlawrence 0:6b5c0ae5acc6 16 #include <wave_player.h>
adamlawrence 0:6b5c0ae5acc6 17
adamlawrence 0:6b5c0ae5acc6 18
adamlawrence 0:6b5c0ae5acc6 19 //-----------------------------------------------------------------------------
adamlawrence 0:6b5c0ae5acc6 20 // constructor -- accepts an mbed pin to use for AnalogOut. Only p18 will work
adamlawrence 0:6b5c0ae5acc6 21 wave_player::wave_player(AnalogOut *_dac)
adamlawrence 0:6b5c0ae5acc6 22 {
adamlawrence 0:6b5c0ae5acc6 23 wave_DAC=_dac;
adamlawrence 0:6b5c0ae5acc6 24 wave_DAC->write_u16(32768); //DAC is 0-3.3V, so idles at ~1.6V
adamlawrence 0:6b5c0ae5acc6 25 verbosity=0;
adamlawrence 0:6b5c0ae5acc6 26 }
adamlawrence 0:6b5c0ae5acc6 27
adamlawrence 0:6b5c0ae5acc6 28 //-----------------------------------------------------------------------------
adamlawrence 0:6b5c0ae5acc6 29 // if verbosity is set then wave player enters a mode where the wave file
adamlawrence 0:6b5c0ae5acc6 30 // is decoded and displayed to the screen, including sample values put into
adamlawrence 0:6b5c0ae5acc6 31 // the DAC FIFO, and values read out of the DAC FIFO by the ISR. The DAC output
adamlawrence 0:6b5c0ae5acc6 32 // itself is so slow as to be unusable, but this might be handy for debugging
adamlawrence 0:6b5c0ae5acc6 33 // wave files that don't play
adamlawrence 0:6b5c0ae5acc6 34 //-----------------------------------------------------------------------------
adamlawrence 0:6b5c0ae5acc6 35 void wave_player::set_verbosity(int v)
adamlawrence 0:6b5c0ae5acc6 36 {
adamlawrence 0:6b5c0ae5acc6 37 verbosity=v;
adamlawrence 0:6b5c0ae5acc6 38 }
adamlawrence 0:6b5c0ae5acc6 39
adamlawrence 0:6b5c0ae5acc6 40 //-----------------------------------------------------------------------------
adamlawrence 0:6b5c0ae5acc6 41 // player function. Takes a pointer to an opened wave file. The file needs
adamlawrence 0:6b5c0ae5acc6 42 // to be stored in a filesystem with enough bandwidth to feed the wave data.
adamlawrence 0:6b5c0ae5acc6 43 // LocalFileSystem isn't, but the SDcard is, at least for 22kHz files. The
adamlawrence 0:6b5c0ae5acc6 44 // SDcard filesystem can be hotrodded by increasing the SPI frequency it uses
adamlawrence 0:6b5c0ae5acc6 45 // internally.
adamlawrence 0:6b5c0ae5acc6 46 //-----------------------------------------------------------------------------
adamlawrence 0:6b5c0ae5acc6 47 void wave_player::play(FILE *wavefile)
adamlawrence 0:6b5c0ae5acc6 48 {
adamlawrence 0:6b5c0ae5acc6 49 unsigned chunk_id,chunk_size,channel;
adamlawrence 0:6b5c0ae5acc6 50 unsigned data,samp_int,i;
adamlawrence 0:6b5c0ae5acc6 51 short unsigned dac_data;
adamlawrence 0:6b5c0ae5acc6 52 long long slice_value;
adamlawrence 0:6b5c0ae5acc6 53 char *slice_buf;
adamlawrence 0:6b5c0ae5acc6 54 short *data_sptr;
adamlawrence 0:6b5c0ae5acc6 55 unsigned char *data_bptr;
adamlawrence 0:6b5c0ae5acc6 56 int *data_wptr;
adamlawrence 0:6b5c0ae5acc6 57 FMT_STRUCT wav_format;
adamlawrence 0:6b5c0ae5acc6 58 long slice,num_slices;
adamlawrence 0:6b5c0ae5acc6 59 DAC_wptr=0;
adamlawrence 0:6b5c0ae5acc6 60 DAC_rptr=0;
adamlawrence 0:6b5c0ae5acc6 61 for (i=0;i<256;i+=2) {
adamlawrence 0:6b5c0ae5acc6 62 DAC_fifo[i]=0;
adamlawrence 0:6b5c0ae5acc6 63 DAC_fifo[i+1]=3000;
adamlawrence 0:6b5c0ae5acc6 64 }
adamlawrence 0:6b5c0ae5acc6 65 DAC_wptr=4;
adamlawrence 0:6b5c0ae5acc6 66 DAC_on=0;
adamlawrence 0:6b5c0ae5acc6 67
adamlawrence 0:6b5c0ae5acc6 68 fread(&chunk_id,4,1,wavefile);
adamlawrence 0:6b5c0ae5acc6 69 fread(&chunk_size,4,1,wavefile);
adamlawrence 0:6b5c0ae5acc6 70 while (!feof(wavefile)) {
adamlawrence 0:6b5c0ae5acc6 71 if (verbosity)
adamlawrence 0:6b5c0ae5acc6 72 printf("Read chunk ID 0x%x, size 0x%x\n",chunk_id,chunk_size);
adamlawrence 0:6b5c0ae5acc6 73 switch (chunk_id) {
adamlawrence 0:6b5c0ae5acc6 74 case 0x46464952:
adamlawrence 0:6b5c0ae5acc6 75 fread(&data,4,1,wavefile);
adamlawrence 0:6b5c0ae5acc6 76 if (verbosity) {
adamlawrence 0:6b5c0ae5acc6 77 printf("RIFF chunk\n");
adamlawrence 0:6b5c0ae5acc6 78 printf(" chunk size %d (0x%x)\n",chunk_size,chunk_size);
adamlawrence 0:6b5c0ae5acc6 79 printf(" RIFF type 0x%x\n",data);
adamlawrence 0:6b5c0ae5acc6 80 }
adamlawrence 0:6b5c0ae5acc6 81 break;
adamlawrence 0:6b5c0ae5acc6 82 case 0x20746d66:
adamlawrence 0:6b5c0ae5acc6 83 fread(&wav_format,sizeof(wav_format),1,wavefile);
adamlawrence 0:6b5c0ae5acc6 84 if (verbosity) {
adamlawrence 0:6b5c0ae5acc6 85 printf("FORMAT chunk\n");
adamlawrence 0:6b5c0ae5acc6 86 printf(" chunk size %d (0x%x)\n",chunk_size,chunk_size);
adamlawrence 0:6b5c0ae5acc6 87 printf(" compression code %d\n",wav_format.comp_code);
adamlawrence 0:6b5c0ae5acc6 88 printf(" %d channels\n",wav_format.num_channels);
adamlawrence 0:6b5c0ae5acc6 89 printf(" %d samples/sec\n",wav_format.sample_rate);
adamlawrence 0:6b5c0ae5acc6 90 printf(" %d bytes/sec\n",wav_format.avg_Bps);
adamlawrence 0:6b5c0ae5acc6 91 printf(" block align %d\n",wav_format.block_align);
adamlawrence 0:6b5c0ae5acc6 92 printf(" %d bits per sample\n",wav_format.sig_bps);
adamlawrence 0:6b5c0ae5acc6 93 }
adamlawrence 0:6b5c0ae5acc6 94 if (chunk_size > sizeof(wav_format))
adamlawrence 0:6b5c0ae5acc6 95 fseek(wavefile,chunk_size-sizeof(wav_format),SEEK_CUR);
adamlawrence 0:6b5c0ae5acc6 96 break;
adamlawrence 0:6b5c0ae5acc6 97 case 0x61746164:
adamlawrence 0:6b5c0ae5acc6 98 // allocate a buffer big enough to hold a slice
adamlawrence 0:6b5c0ae5acc6 99 slice_buf=(char *)malloc(wav_format.block_align);
adamlawrence 0:6b5c0ae5acc6 100 if (!slice_buf) {
adamlawrence 0:6b5c0ae5acc6 101 printf("Unable to malloc slice buffer");
adamlawrence 0:6b5c0ae5acc6 102 exit(1);
adamlawrence 0:6b5c0ae5acc6 103 }
adamlawrence 0:6b5c0ae5acc6 104 num_slices=chunk_size/wav_format.block_align;
adamlawrence 0:6b5c0ae5acc6 105 samp_int=1000000/(wav_format.sample_rate);
adamlawrence 0:6b5c0ae5acc6 106 if (verbosity) {
adamlawrence 0:6b5c0ae5acc6 107 printf("DATA chunk\n");
adamlawrence 0:6b5c0ae5acc6 108 printf(" chunk size %d (0x%x)\n",chunk_size,chunk_size);
adamlawrence 0:6b5c0ae5acc6 109 printf(" %d slices\n",num_slices);
adamlawrence 0:6b5c0ae5acc6 110 printf(" Ideal sample interval=%d\n",(unsigned)(1000000.0/wav_format.sample_rate));
adamlawrence 0:6b5c0ae5acc6 111 printf(" programmed interrupt tick interval=%d\n",samp_int);
adamlawrence 0:6b5c0ae5acc6 112 }
adamlawrence 0:6b5c0ae5acc6 113
adamlawrence 0:6b5c0ae5acc6 114 // starting up ticker to write samples out -- no printfs until tick.detach is called
adamlawrence 0:6b5c0ae5acc6 115 if (verbosity)
adamlawrence 0:6b5c0ae5acc6 116 tick.attach_us(this,&wave_player::dac_out, 500000);
adamlawrence 0:6b5c0ae5acc6 117 else
adamlawrence 0:6b5c0ae5acc6 118 tick.attach_us(this,&wave_player::dac_out, samp_int);
adamlawrence 0:6b5c0ae5acc6 119 DAC_on=1;
adamlawrence 0:6b5c0ae5acc6 120
adamlawrence 0:6b5c0ae5acc6 121 // start reading slices, which contain one sample each for however many channels
adamlawrence 0:6b5c0ae5acc6 122 // are in the wave file. one channel=mono, two channels=stereo, etc. Since
adamlawrence 0:6b5c0ae5acc6 123 // mbed only has a single AnalogOut, all of the channels present are averaged
adamlawrence 0:6b5c0ae5acc6 124 // to produce a single sample value. This summing and averaging happens in
adamlawrence 0:6b5c0ae5acc6 125 // a variable of type signed long long, to make sure that the data doesn't
adamlawrence 0:6b5c0ae5acc6 126 // overflow regardless of sample size (8 bits, 16 bits, 32 bits).
adamlawrence 0:6b5c0ae5acc6 127 //
adamlawrence 0:6b5c0ae5acc6 128 // note that from what I can find that 8 bit wave files use unsigned data,
adamlawrence 0:6b5c0ae5acc6 129 // while 16 and 32 bit wave files use signed data
adamlawrence 0:6b5c0ae5acc6 130 //
adamlawrence 0:6b5c0ae5acc6 131 for (slice=0;slice<num_slices;slice+=1) {
adamlawrence 0:6b5c0ae5acc6 132 fread(slice_buf,wav_format.block_align,1,wavefile);
adamlawrence 0:6b5c0ae5acc6 133 if (feof(wavefile)) {
adamlawrence 0:6b5c0ae5acc6 134 printf("Oops -- not enough slices in the wave file\n");
adamlawrence 0:6b5c0ae5acc6 135 exit(1);
adamlawrence 0:6b5c0ae5acc6 136 }
adamlawrence 0:6b5c0ae5acc6 137 data_sptr=(short *)slice_buf; // 16 bit samples
adamlawrence 0:6b5c0ae5acc6 138 data_bptr=(unsigned char *)slice_buf; // 8 bit samples
adamlawrence 0:6b5c0ae5acc6 139 data_wptr=(int *)slice_buf; // 32 bit samples
adamlawrence 0:6b5c0ae5acc6 140 slice_value=0;
adamlawrence 0:6b5c0ae5acc6 141 for (channel=0;channel<wav_format.num_channels;channel++) {
adamlawrence 0:6b5c0ae5acc6 142 switch (wav_format.sig_bps) {
adamlawrence 0:6b5c0ae5acc6 143 case 16:
adamlawrence 0:6b5c0ae5acc6 144 if (verbosity)
adamlawrence 0:6b5c0ae5acc6 145 printf("16 bit channel %d data=%d ",channel,data_sptr[channel]);
adamlawrence 0:6b5c0ae5acc6 146 slice_value+=data_sptr[channel];
adamlawrence 0:6b5c0ae5acc6 147 break;
adamlawrence 0:6b5c0ae5acc6 148 case 32:
adamlawrence 0:6b5c0ae5acc6 149 if (verbosity)
adamlawrence 0:6b5c0ae5acc6 150 printf("32 bit channel %d data=%d ",channel,data_wptr[channel]);
adamlawrence 0:6b5c0ae5acc6 151 slice_value+=data_wptr[channel];
adamlawrence 0:6b5c0ae5acc6 152 break;
adamlawrence 0:6b5c0ae5acc6 153 case 8:
adamlawrence 0:6b5c0ae5acc6 154 if (verbosity)
adamlawrence 0:6b5c0ae5acc6 155 printf("8 bit channel %d data=%d ",channel,(int)data_bptr[channel]);
adamlawrence 0:6b5c0ae5acc6 156 slice_value+=data_bptr[channel];
adamlawrence 0:6b5c0ae5acc6 157 break;
adamlawrence 0:6b5c0ae5acc6 158 }
adamlawrence 0:6b5c0ae5acc6 159 }
adamlawrence 0:6b5c0ae5acc6 160 slice_value/=wav_format.num_channels;
adamlawrence 0:6b5c0ae5acc6 161
adamlawrence 0:6b5c0ae5acc6 162 // slice_value is now averaged. Next it needs to be scaled to an unsigned 16 bit value
adamlawrence 0:6b5c0ae5acc6 163 // with DC offset so it can be written to the DAC.
adamlawrence 0:6b5c0ae5acc6 164 switch (wav_format.sig_bps) {
adamlawrence 0:6b5c0ae5acc6 165 case 8: slice_value<<=8;
adamlawrence 0:6b5c0ae5acc6 166 break;
adamlawrence 0:6b5c0ae5acc6 167 case 16: slice_value+=32768;
adamlawrence 0:6b5c0ae5acc6 168 break;
adamlawrence 0:6b5c0ae5acc6 169 case 32: slice_value>>=16;
adamlawrence 0:6b5c0ae5acc6 170 slice_value+=32768;
adamlawrence 0:6b5c0ae5acc6 171 break;
adamlawrence 0:6b5c0ae5acc6 172 }
adamlawrence 0:6b5c0ae5acc6 173 dac_data=(short unsigned)slice_value;
adamlawrence 0:6b5c0ae5acc6 174 if (verbosity)
adamlawrence 0:6b5c0ae5acc6 175 printf("sample %d wptr %d slice_value %d dac_data %u\n",slice,DAC_wptr,(int)slice_value,dac_data);
adamlawrence 0:6b5c0ae5acc6 176 DAC_fifo[DAC_wptr]=dac_data;
adamlawrence 0:6b5c0ae5acc6 177 DAC_wptr=(DAC_wptr+1) & 0xff;
adamlawrence 0:6b5c0ae5acc6 178 while (DAC_wptr==DAC_rptr) {
adamlawrence 0:6b5c0ae5acc6 179 }
adamlawrence 0:6b5c0ae5acc6 180 }
adamlawrence 0:6b5c0ae5acc6 181 DAC_on=0;
adamlawrence 0:6b5c0ae5acc6 182 tick.detach();
adamlawrence 0:6b5c0ae5acc6 183 free(slice_buf);
adamlawrence 0:6b5c0ae5acc6 184 break;
adamlawrence 0:6b5c0ae5acc6 185 case 0x5453494c:
adamlawrence 0:6b5c0ae5acc6 186 if (verbosity)
adamlawrence 0:6b5c0ae5acc6 187 printf("INFO chunk, size %d\n",chunk_size);
adamlawrence 0:6b5c0ae5acc6 188 fseek(wavefile,chunk_size,SEEK_CUR);
adamlawrence 0:6b5c0ae5acc6 189 break;
adamlawrence 0:6b5c0ae5acc6 190 default:
adamlawrence 0:6b5c0ae5acc6 191 printf("unknown chunk type 0x%x, size %d\n",chunk_id,chunk_size);
adamlawrence 0:6b5c0ae5acc6 192 data=fseek(wavefile,chunk_size,SEEK_CUR);
adamlawrence 0:6b5c0ae5acc6 193 break;
adamlawrence 0:6b5c0ae5acc6 194 }
adamlawrence 0:6b5c0ae5acc6 195 fread(&chunk_id,4,1,wavefile);
adamlawrence 0:6b5c0ae5acc6 196 fread(&chunk_size,4,1,wavefile);
adamlawrence 0:6b5c0ae5acc6 197 }
adamlawrence 0:6b5c0ae5acc6 198 }
adamlawrence 0:6b5c0ae5acc6 199
adamlawrence 0:6b5c0ae5acc6 200
adamlawrence 0:6b5c0ae5acc6 201 void wave_player::dac_out()
adamlawrence 0:6b5c0ae5acc6 202 {
adamlawrence 0:6b5c0ae5acc6 203 if (DAC_on) {
adamlawrence 0:6b5c0ae5acc6 204 #ifdef VERBOSE
adamlawrence 0:6b5c0ae5acc6 205 printf("ISR rdptr %d got %u\n",DAC_rptr,DAC_fifo[DAC_rptr]);
adamlawrence 0:6b5c0ae5acc6 206 #endif
adamlawrence 0:6b5c0ae5acc6 207 wave_DAC->write_u16(DAC_fifo[DAC_rptr]);
adamlawrence 0:6b5c0ae5acc6 208 DAC_rptr=(DAC_rptr+1) & 0xff;
adamlawrence 0:6b5c0ae5acc6 209 }
adamlawrence 0:6b5c0ae5acc6 210 }
adamlawrence 0:6b5c0ae5acc6 211