Vlad Cazan
/
WavePlayer
Revision 0:143457f10e26, committed 2009-12-06
- Comitter:
- vcazan
- Date:
- Sun Dec 06 17:08:31 2009 +0000
- Commit message:
Changed in this revision
diff -r 000000000000 -r 143457f10e26 FATFileSystem.lib --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/FATFileSystem.lib Sun Dec 06 17:08:31 2009 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_unsupported/code/fatfilesystem/ \ No newline at end of file
diff -r 000000000000 -r 143457f10e26 SDFileSystem.lib --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/SDFileSystem.lib Sun Dec 06 17:08:31 2009 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_unsupported/code/sdfilesystem/ \ No newline at end of file
diff -r 000000000000 -r 143457f10e26 main.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/main.cpp Sun Dec 06 17:08:31 2009 +0000 @@ -0,0 +1,191 @@ +//todo red button and light sensor + + +#include "mbed.h" +#include "SDFileSystem.h" + +AnalogOut DACout(p18); +DigitalOut led1(LED1); +DigitalOut led2(LED2); +DigitalOut led3(LED3); +DigitalOut led4(LED4); +DigitalOut digout(p8); +Ticker tick; +SDFileSystem sd(p5, p6, p7, p13, "sd"); + +#define SAMPLE_FREQ 40000 +#define BUF_SIZE (SAMPLE_FREQ/10) +#define SLICE_BUF_SIZE 1 + +void dac_out(void); +void play_wave(char *); +void cleanup(char *); +void fill_adc_buf(short *, unsigned); +void swapword(unsigned *); + +// a FIFO for the DAC +short DAC_fifo[256]; +short DAC_wptr; +short DAC_rptr; +short DAC_on; + +typedef struct uFMT_STRUCT { + short comp_code; + short num_channels; + unsigned sample_rate; + unsigned avg_Bps; + short block_align; + short sig_bps; +} FMT_STRUCT; + + +int main() { + led1=0; wait(.5); led1=1; wait(.5); led1=0; + printf("Hello, world!\n"); + play_wave("/sd/baddonut.wav"); + printf("Back from play_wave()\n"); + play_wave("/sd/clint16.wav"); + printf("Back from play_wave()\n"); + printf("Goodbye, world!\n"); +} + +void play_wave(char *wavname) +{ + unsigned chunk_id,chunk_size,channel; + unsigned *data_wptr,data,samp_int,i; + short dac_data; + char *slice_buf; + short *data_sptr; + char *data_bptr; + FMT_STRUCT wav_format; + FILE *wavfile; + long slice,num_slices; + DAC_wptr=0; + DAC_rptr=0; + for (i=0;i<256;i+=2) { + DAC_fifo[i]=0; + DAC_fifo[i+1]=3000; + } + DAC_wptr=4; + DAC_on=0; + + led1=led2=led3=led4=0; + + printf("Playing wave file '%s'\n",wavname); + + wavfile=fopen(wavname,"rb"); + if (!wavfile) { + printf("Unable to open wav file '%s'\n",wavname); + exit(1); + } + + fread(&chunk_id,4,1,wavfile); + fread(&chunk_size,4,1,wavfile); + while (!feof(wavfile)) { + printf("Read chunk ID 0x%x, size 0x%x\n",chunk_id,chunk_size); + switch (chunk_id) { + case 0x46464952: + fread(&data,4,1,wavfile); + printf("RIFF chunk\n"); + printf(" chunk size %d (0x%x)\n",chunk_size,chunk_size); + printf(" RIFF type 0x%x\n",data); + break; + case 0x20746d66: + fread(&wav_format,sizeof(wav_format),1,wavfile); + printf("FORMAT chunk\n"); + printf(" chunk size %d (0x%x)\n",chunk_size,chunk_size); + printf(" compression code %d\n",wav_format.comp_code); + printf(" %d channels\n",wav_format.num_channels); + printf(" %d samples/sec\n",wav_format.sample_rate); + printf(" %d bytes/sec\n",wav_format.avg_Bps); + printf(" block align %d\n",wav_format.block_align); + printf(" %d bits per sample\n",wav_format.sig_bps); + if (chunk_size > sizeof(wav_format)) + fseek(wavfile,chunk_size-sizeof(wav_format),SEEK_CUR); +// create a slice buffer large enough to hold multiple slices + slice_buf=(char *)malloc(wav_format.block_align*SLICE_BUF_SIZE); + if (!slice_buf) { + printf("Unable to malloc slice buffer"); + exit(1); + } + break; + case 0x61746164: + slice_buf=(char *)malloc(wav_format.block_align*SLICE_BUF_SIZE); + if (!slice_buf) { + printf("Unable to malloc slice buffer"); + exit(1); + } num_slices=chunk_size/wav_format.block_align; + printf("DATA chunk\n"); + printf(" chunk size %d (0x%x)\n",chunk_size,chunk_size); + printf(" %d slices\n",num_slices); + printf(" Ideal sample interval=%d\n",(unsigned)(1000000.0/wav_format.sample_rate)); + samp_int=1000000/(wav_format.sample_rate); + printf(" programmed interrupt tick interval=%d\n",samp_int); + +// starting up ticker to write samples out -- no printfs until tick.detach is called + tick.attach_us(&dac_out, samp_int); + DAC_on=1; + led2=1; + for (slice=0;slice<num_slices;slice+=SLICE_BUF_SIZE) { + fread(slice_buf,wav_format.block_align*SLICE_BUF_SIZE,1,wavfile); + if (feof(wavfile)) { + printf("Oops -- not enough slices in the wave file\n"); + exit(1); + } + data_sptr=(short *)slice_buf; + for (i=0;i<SLICE_BUF_SIZE;i++) { + dac_data=0; + +// for a stereo wave file average the two channels. + for (channel=0;channel<wav_format.num_channels;channel++) { + switch (wav_format.sig_bps) { + case 16: + dac_data+=( ((int)(*data_sptr++)) +32768)>>5; + break; + } + } + dac_data>>=1; + DAC_fifo[DAC_wptr]=dac_data; + DAC_wptr=(DAC_wptr+1) & 0xff; + while (DAC_wptr==DAC_rptr) { + led1=1; + } + led1=0; + } + } + DAC_on=0; + led2=0; + tick.detach(); + printf("Ticker detached\n"); + led3=1; + free(slice_buf); + break; + case 0x5453494c: + printf("INFO chunk, size %d\n",chunk_size); + fseek(wavfile,chunk_size,SEEK_CUR); + break; + default: + printf("unknown chunk type 0x%x, size %d\n",chunk_id,chunk_size); + data=fseek(wavfile,chunk_size,SEEK_CUR); + break; + } + fread(&chunk_id,4,1,wavfile); + fread(&chunk_size,4,1,wavfile); + } + printf("Done with wave file\n"); + fclose(wavfile); + led1=0; +} + + +void dac_out() +{ + if (DAC_on) { + digout=1; + DACout.write(DAC_fifo[DAC_rptr]); + DAC_rptr=(DAC_rptr+1) & 0xff; + digout=0; + } +} + +
diff -r 000000000000 -r 143457f10e26 mbed.bld --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Sun Dec 06 17:08:31 2009 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/49a220cc26e0