Diff: main.cpp

Revision:

3:64c3ed0fc4b4

Parent:

2:baf5bf51cd28

--- a/main.cpp	Fri Sep 03 08:21:29 2010 +0000
+++ b/main.cpp	Sat Sep 11 11:23:26 2010 +0000
@@ -1,10 +1,9 @@
 /* DPCM & Rice Golomb Lossless Audio Player and Realtime encoder */
 #include "SDHCFileSystem.h"
-
 #include "mbed.h"
 #include "string"
+#include "_bitio.h"
 
-#include "_bitio.h"
 //FILE    *infp,*outfp;
 SDFileSystem sd(p5, p6, p7, p8, "sd");
 DigitalOut led1(LED1);
@@ -12,25 +11,41 @@
 AnalogOut DACout(p18);
 Ticker tick;
 
+// BU9480F define
+SPI bu9480f(p11,p12,p13);
+DigitalOut LRCLK(p14);
+// BU9480F define.end
+
+
 // a FIFO for the DAC
-#define RAM_LENGTH 4096//8192
+#define TXFIFO_FULL 1
+#define RAM_LENGTH 8192//8192
 #define RAM_LIMIT (RAM_LENGTH - 1) 
 volatile short DAC_fifo[RAM_LENGTH];
 volatile short DAC_wptr=0;
 volatile short DAC_rptr=0;
 volatile short DAC_on;
-volatile short int DAC_diff=0;
+volatile short DAC_diff=0;
 
 void dac_out()
 {
   //  printf("\t%d\r\n",DAC_diff);
-    if (DAC_diff > 0) {
-        led2 = 0;
-        DACout.write_u16(DAC_fifo[DAC_rptr]);
-        DAC_rptr=(DAC_rptr+1) & (RAM_LIMIT);
-        DAC_diff--;
+    if (DAC_diff > 1) {
+        led2 = 0;        
+        
+        LRCLK = 0;
+        bu9480f.write(DAC_fifo[DAC_rptr++]);
+        DAC_rptr &= RAM_LIMIT;
+        
+        LRCLK = 1;
+        bu9480f.write(DAC_fifo[DAC_rptr++]);
+        DAC_rptr &= RAM_LIMIT;
+        
+        DAC_diff-=2;
+        
    }else led2 = 1;
 }
+
 void encode(long int n){
     int zero_shift = 0;
     
@@ -59,12 +74,12 @@
 
 
 void decode(void){
-    short dac_data;
+    //short dac_data;
     long int decode_buff;
     short diff,diff2;
     unsigned int buff_sign,zero_shift;
     //char flag;
-
+    
     diff = 0;
     diff2 = 0;
     // get sign(1 for positive, 0 for negative)
@@ -80,19 +95,13 @@
         if(!buff_sign)decode_buff =- decode_buff;
         /* return decode_buff; */
         diff =(diff + decode_buff);
-        
-        dac_data = ((int)diff + 32768) >> 1;
-        DAC_fifo[DAC_wptr]=dac_data;
-        DAC_wptr=(DAC_wptr+1) & (RAM_LIMIT);
-        DAC_diff=(DAC_diff+1);
+        DAC_fifo[DAC_wptr++]=(short)diff;
+        DAC_wptr &= RAM_LIMIT;
+        //DAC_diff++;
         while (DAC_diff > RAM_LIMIT){
             led1 = 1;
         }   //wait
         led1=0;
-        if(DAC_diff <= 0)
-            led2=1;
-        else led2=0;
- 
         
         if((buff_sign = getbit())==OVERRUN)break;
         zero_shift = 0;
@@ -105,11 +114,14 @@
         /* return decode_buff; */
         diff2 =(diff2 + decode_buff);
 
-       /* 
-        drawc((unsigned char)diff2 & 0xff);
-        drawc((unsigned char)((diff2>>8) &0xff));
-        */
-        //fwrite(&diff2, sizeof(short int), 1, outfp);
+        DAC_fifo[DAC_wptr++]=(short)diff2;
+        DAC_wptr &= RAM_LIMIT;
+        DAC_diff+=2;
+        
+        while (DAC_diff > RAM_LIMIT){
+            led1 = 1;
+        }   //wait
+        led1=0;
         
     
          
@@ -124,8 +136,13 @@
         printf( "\r\nError: The message file cannot be accessed\r\n" );
         return -1;
     }
-    //tick.detach();
-    tick.attach_us(&dac_out, 45); //set 22.050kHz sampling data    
+    // bu9480f init
+    bu9480f.format(16,0);
+    bu9480f.frequency(16000000); //16MHz
+    // bu9480f init.end
+    
+      
+    tick.attach_us(&dac_out, 41); //set 24.000kHz sampling data   
     decode();
     tick.detach();