Tom Coxon
Demo of Embedded Artists LPCXpresso baseboard SD card reader and audio facilities. Updated to put wav file player in a separate library and use the high capacity SD card library provided by Klaus Bu.
Revision 0:1f4b7aa80ab3, committed 2010-07-03
- Comitter:
- tom_coxon
- Date:
- Sat Jul 03 10:07:07 2010 +0000
- Child:
- 1:22c43c468a2f
- Commit message:
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/FATFileSystem.lib Sat Jul 03 10:07:07 2010 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_unsupported/code/fatfilesystem/ \ No newline at end of file
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/SDFileSystem.lib Sat Jul 03 10:07:07 2010 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/simon/code/SDFileSystem/#b1ddfc9a9b25
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Sat Jul 03 10:07:07 2010 +0000
@@ -0,0 +1,245 @@
+/*
+ Demo of Embedded Artists LPCXpresso baseboard SD card
+ reader and audio facilities.
+
+ WAVEplayer by Vlad Cazan/Stephan Rochon modified by Tom Coxon
+ to run correctly on the Embedded Artists LPCXpresso baseboard.
+
+ Also modified to play 8 bit sample size in addition to
+ original 16 bit.
+
+ Place suitable wav files with 8 or 16 bit sample sizes on the
+ SD card and ensure the file names are 8.3 format. Then change
+ the main method below to the relevant file paths.
+
+ Please set all jumpers on board to the default case except for
+ the following:
+
+ Audio setup:
+
+ 1. Insert a jumper in J31 to connect signal PIO1_2 to the low
+ pass filer as described in section 4.7.2. of base board users
+ guide.
+
+ 2. Insert three jumpers in J33 to connect PIO3_0, PIO3_1 and
+ PIO3_2 to control the amplifier as described in section 4.8
+ of base board users guide.
+
+ 3. Insert a jumper in J32 and remove any from J34 to use the
+ internal speaker as described in section 4.8
+ of base board users guide.
+
+ SD Card setup:
+
+ 4. Insert all five jumpers in J39 as described in section 4.3.3
+ of base board users guide.
+
+ 5. Remove jumper marked "A" in J55 In order to connect PIO1_11
+ to CS signal of J40 (the SPI-SSEL signal) as described in section 4.3.3
+ of base board users guide.
+*/
+
+#include "mbed.h"
+#include "SDFileSystem.h"
+
+AnalogOut DACout(p18);
+DigitalOut led1(LED1);
+DigitalOut led2(LED2);
+DigitalOut led3(LED3);
+DigitalOut led4(LED4);
+Ticker tick;
+SDFileSystem sd(p5, p6, p7, p24, "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("\r\n--------------- Starting -----------------\r\n");
+
+ play_wave("/sd/startup.wav"); // 8 bit sample size
+
+ play_wave("/sd/baddonut.wav"); // 16 bit sample size
+
+ play_wave("/sd/dduck.wav"); // 8 bit sample size
+
+ play_wave("/sd/bbunny.wav"); // 8 bit sample size
+
+ play_wave("/sd/clint16.wav"); // 16 bit sample size
+
+ printf("<<<<<<<<<<<<<<<< All done >>>>>>>>>>>>>>>>\r\n");
+ led1=1;
+ wait(.5);
+ led1=0;
+ wait(.5);
+ led1=1;
+}
+
+void play_wave(char *wavname) {
+ unsigned chunk_id,chunk_size,channel;
+ unsigned data,samp_int,i;
+ short dac_data;
+ char *slice_buf;
+ short *data_sptr;
+ 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'\r\n",wavname);
+
+ wavfile=fopen(wavname,"rb");
+ if (!wavfile) {
+ printf("Unable to open wav file '%s'\r\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\r\n",chunk_id,chunk_size);
+ switch (chunk_id) {
+ case 0x46464952:
+ fread(&data,4,1,wavfile);
+ printf("RIFF chunk\r\n");
+ printf(" chunk size %d (0x%x)\r\n",chunk_size,chunk_size);
+ printf(" RIFF type 0x%x\r\n",data);
+ break;
+ case 0x20746d66:
+ fread(&wav_format,sizeof(wav_format),1,wavfile);
+ printf("FORMAT chunk\r\n");
+ printf(" chunk size %d (0x%x)\r\n",chunk_size,chunk_size);
+ printf(" compression code %d\r\n",wav_format.comp_code);
+ printf(" %d channels\r\n",wav_format.num_channels);
+ printf(" %d samples/sec\r\n",wav_format.sample_rate);
+ printf(" %d bytes/sec\r\n",wav_format.avg_Bps);
+ printf(" block align %d\r\n",wav_format.block_align);
+ printf(" %d bits per sample\r\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\r\n");
+ printf(" chunk size %d (0x%x)\r\n",chunk_size,chunk_size);
+ printf(" %d slices\r\n",num_slices);
+ printf(" Ideal sample interval=%d\r\n",(unsigned)(1000000.0/wav_format.sample_rate));
+ samp_int=1000000/(wav_format.sample_rate);
+ printf(" programmed interrupt tick interval=%d\r\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\r\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 );
+ break;
+ case 8:
+ dac_data+=( ((int)(*data_sptr++)) +32768 <<8);
+ break;
+ }
+ }
+ DAC_fifo[DAC_wptr]=dac_data;
+ DAC_wptr=(DAC_wptr+1) & 0xff;
+ while (DAC_wptr==DAC_rptr) {
+ led1=1;
+ wait_us(10);
+ }
+ led1=0;
+ }
+ }
+ DAC_on=0;
+ led2=0;
+ tick.detach();
+ printf("Ticker detached\r\n");
+ led3=1;
+ free(slice_buf);
+ break;
+ case 0x5453494c:
+ printf("INFO chunk, size %d\r\n",chunk_size);
+ fseek(wavfile,chunk_size,SEEK_CUR);
+ break;
+ default:
+ printf("unknown chunk type 0x%x, size %d\r\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 ++++++++++\r\n");
+ fclose(wavfile);
+ led1=0;
+}
+
+
+void dac_out() {
+ if (DAC_on) {
+ led4=1;
+ DACout.write_u16(DAC_fifo[DAC_rptr]);
+ DAC_rptr=(DAC_rptr+1) & 0xff;
+ led4=0;
+ }
+}
+
+
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Sat Jul 03 10:07:07 2010 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/3944f1e2fa4f