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Dependencies: 4DGL-uLCD-SE Physac-MBED PinDetect SDFileSystem mbed-rtos mbed
Diff: wave_player_appbd/wave_player.cpp
- Revision:
- 21:df9e8f45e14c
- Parent:
- 6:fc95af217f01
diff -r 73e4f12277bd -r df9e8f45e14c wave_player_appbd/wave_player.cpp --- a/wave_player_appbd/wave_player.cpp Mon Dec 05 20:51:36 2022 +0000 +++ b/wave_player_appbd/wave_player.cpp Tue Dec 06 22:09:51 2022 +0000 @@ -20,9 +20,9 @@ // constructor -- accepts an mbed pin to use for AnalogOut. Only p18 will work wave_player::wave_player(AnalogOut *_dac) { - wave_DAC=_dac; - wave_DAC->write_u16(32768); //DAC is 0-3.3V, so idles at ~1.6V - verbosity=0; + wave_DAC=_dac; + wave_DAC->write_u16(32768); //DAC is 0-3.3V, so idles at ~1.6V + verbosity=0; } //----------------------------------------------------------------------------- @@ -34,7 +34,7 @@ //----------------------------------------------------------------------------- void wave_player::set_verbosity(int v) { - verbosity=v; + verbosity=v; } //----------------------------------------------------------------------------- @@ -46,77 +46,77 @@ //----------------------------------------------------------------------------- void wave_player::play(FILE *wavefile) { - unsigned chunk_id,chunk_size,channel; - unsigned data,samp_int,i; - short unsigned dac_data; - long long slice_value; - char *slice_buf; - short *data_sptr; - unsigned char *data_bptr; - int *data_wptr; - FMT_STRUCT wav_format; - 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; + unsigned chunk_id,chunk_size,channel; + unsigned data,samp_int,i; + short unsigned dac_data; + long long slice_value; + char *slice_buf; + short *data_sptr; + unsigned char *data_bptr; + int *data_wptr; + FMT_STRUCT wav_format; + 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; - fread(&chunk_id,4,1,wavefile); - fread(&chunk_size,4,1,wavefile); - while (!feof(wavefile)) { - if (verbosity) - printf("Read chunk ID 0x%x, size 0x%x\n",chunk_id,chunk_size); - switch (chunk_id) { - case 0x46464952: - fread(&data,4,1,wavefile); - if (verbosity) { - 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,wavefile); - if (verbosity) { - 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(wavefile,chunk_size-sizeof(wav_format),SEEK_CUR); - break; - case 0x61746164: + fread(&chunk_id,4,1,wavefile); + fread(&chunk_size,4,1,wavefile); + while (!feof(wavefile)) { + if (verbosity) + printf("Read chunk ID 0x%x, size 0x%x\n",chunk_id,chunk_size); + switch (chunk_id) { + case 0x46464952: + fread(&data,4,1,wavefile); + if (verbosity) { + 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,wavefile); + if (verbosity) { + 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(wavefile,chunk_size-sizeof(wav_format),SEEK_CUR); + break; + case 0x61746164: // allocate a buffer big enough to hold a slice - slice_buf=(char *)malloc(wav_format.block_align); - if (!slice_buf) { - printf("Unable to malloc slice buffer"); - exit(1); - } - num_slices=chunk_size/wav_format.block_align; - samp_int=1000000/(wav_format.sample_rate); - if (verbosity) { - 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)); - printf(" programmed interrupt tick interval=%d\n",samp_int); - } + slice_buf=(char *)malloc(wav_format.block_align); + if (!slice_buf) { + printf("Unable to malloc slice buffer"); + exit(1); + } + num_slices=chunk_size/wav_format.block_align; + samp_int=1000000/(wav_format.sample_rate); + if (verbosity) { + 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)); + printf(" programmed interrupt tick interval=%d\n",samp_int); + } // starting up ticker to write samples out -- no printfs until tick.detach is called - if (verbosity) - tick.attach_us(this,&wave_player::dac_out, 500000); - else - tick.attach_us(this,&wave_player::dac_out, samp_int); - DAC_on=1; + if (verbosity) + tick.attach_us(this,&wave_player::dac_out, 500000); + else + tick.attach_us(this,&wave_player::dac_out, samp_int); + DAC_on=1; // start reading slices, which contain one sample each for however many channels // are in the wave file. one channel=mono, two channels=stereo, etc. Since @@ -128,84 +128,87 @@ // note that from what I can find that 8 bit wave files use unsigned data, // while 16 and 32 bit wave files use signed data // - for (slice=0;slice<num_slices;slice+=1) { - fread(slice_buf,wav_format.block_align,1,wavefile); - if (feof(wavefile)) { - printf("Oops -- not enough slices in the wave file\n"); - exit(1); - } - data_sptr=(short *)slice_buf; // 16 bit samples - data_bptr=(unsigned char *)slice_buf; // 8 bit samples - data_wptr=(int *)slice_buf; // 32 bit samples - slice_value=0; - for (channel=0;channel<wav_format.num_channels;channel++) { - switch (wav_format.sig_bps) { - case 16: - if (verbosity) - printf("16 bit channel %d data=%d ",channel,data_sptr[channel]); - slice_value+=data_sptr[channel]; - break; - case 32: - if (verbosity) - printf("32 bit channel %d data=%d ",channel,data_wptr[channel]); - slice_value+=data_wptr[channel]; - break; - case 8: - if (verbosity) - printf("8 bit channel %d data=%d ",channel,(int)data_bptr[channel]); - slice_value+=data_bptr[channel]; - break; - } - } - slice_value/=wav_format.num_channels; - + for (slice=0; slice<num_slices; slice+=1) { + fread(slice_buf,wav_format.block_align,1,wavefile); + if (feof(wavefile)) { + printf("Oops -- not enough slices in the wave file\n"); + exit(1); + } + data_sptr=(short *)slice_buf; // 16 bit samples + data_bptr=(unsigned char *)slice_buf; // 8 bit samples + data_wptr=(int *)slice_buf; // 32 bit samples + slice_value=0; + for (channel=0; channel<wav_format.num_channels; channel++) { + switch (wav_format.sig_bps) { + case 16: + if (verbosity) + printf("16 bit channel %d data=%d ",channel,data_sptr[channel]); + slice_value+=data_sptr[channel]; + break; + case 32: + if (verbosity) + printf("32 bit channel %d data=%d ",channel,data_wptr[channel]); + slice_value+=data_wptr[channel]; + break; + case 8: + if (verbosity) + printf("8 bit channel %d data=%d ",channel,(int)data_bptr[channel]); + slice_value+=data_bptr[channel]; + break; + } + } + slice_value/=wav_format.num_channels; + // slice_value is now averaged. Next it needs to be scaled to an unsigned 16 bit value // with DC offset so it can be written to the DAC. - switch (wav_format.sig_bps) { - case 8: slice_value<<=8; - break; - case 16: slice_value+=32768; - break; - case 32: slice_value>>=16; - slice_value+=32768; - break; - } - dac_data=(short unsigned)slice_value; - if (verbosity) - printf("sample %d wptr %d slice_value %d dac_data %u\n",slice,DAC_wptr,(int)slice_value,dac_data); - DAC_fifo[DAC_wptr]=dac_data; - DAC_wptr=(DAC_wptr+1) & 0xff; - while (DAC_wptr==DAC_rptr) { - } + switch (wav_format.sig_bps) { + case 8: + slice_value<<=8; + break; + case 16: + slice_value+=32768; + break; + case 32: + slice_value>>=16; + slice_value+=32768; + break; + } + dac_data=(short unsigned)slice_value; + if (verbosity) + printf("sample %d wptr %d slice_value %d dac_data %u\n",slice,DAC_wptr,(int)slice_value,dac_data); + DAC_fifo[DAC_wptr]=dac_data; + DAC_wptr=(DAC_wptr+1) & 0xff; + while (DAC_wptr==DAC_rptr) { + } + } + DAC_on=0; + tick.detach(); + free(slice_buf); + break; + case 0x5453494c: + if (verbosity) + printf("INFO chunk, size %d\n",chunk_size); + fseek(wavefile,chunk_size,SEEK_CUR); + break; + default: + printf("unknown chunk type 0x%x, size %d\n",chunk_id,chunk_size); + data=fseek(wavefile,chunk_size,SEEK_CUR); + break; } - DAC_on=0; - tick.detach(); - free(slice_buf); - break; - case 0x5453494c: - if (verbosity) - printf("INFO chunk, size %d\n",chunk_size); - fseek(wavefile,chunk_size,SEEK_CUR); - break; - default: - printf("unknown chunk type 0x%x, size %d\n",chunk_id,chunk_size); - data=fseek(wavefile,chunk_size,SEEK_CUR); - break; + fread(&chunk_id,4,1,wavefile); + fread(&chunk_size,4,1,wavefile); } - fread(&chunk_id,4,1,wavefile); - fread(&chunk_size,4,1,wavefile); - } } void wave_player::dac_out() { - if (DAC_on) { + if (DAC_on) { #ifdef VERBOSE - printf("ISR rdptr %d got %u\n",DAC_rptr,DAC_fifo[DAC_rptr]); + printf("ISR rdptr %d got %u\n",DAC_rptr,DAC_fifo[DAC_rptr]); #endif - wave_DAC->write_u16(DAC_fifo[DAC_rptr]); - DAC_rptr=(DAC_rptr+1) & 0xff; - } + wave_DAC->write_u16(DAC_fifo[DAC_rptr]); + DAC_rptr=(DAC_rptr+1) & 0xff; + } }