Revision 2:79b8132da1d6, committed 2019-01-06

Comitter:

graffou

Date:

Sun Jan 06 17:14:36 2019 +0000

Parent:

1:6349099b6962

Commit message:

ADAT encoder + decoder, with much more cleaner code.; CPU usage for encoder+decoder is ~40% (~4s codec over 480000 frames)

Changed in this revision

diff -r 6349099b6962 -r 79b8132da1d6 main.cpp
--- a/main.cpp	Sun Jan 06 14:55:09 2019 +0000
+++ b/main.cpp	Sun Jan 06 17:14:36 2019 +0000
@@ -38,6 +38,8 @@
 uint32_t data[8]; // 24-bit audio in 
 uint32_t adat[8]; // raw ADAT frame
 uint32_t adat_nrz[8]; // NRZI encoded ADAT frame
+uint32_t dec_nrz[8]; // NRZI decoded ADAT frame
+uint32_t adec[8]; // audio decoded frame
 
 DigitalIn pb(USER_BUTTON);
 DigitalOut myled(LED1);
@@ -70,6 +72,109 @@
   *x = ((*x)>>1) | ((*x)<<(31));
 }
 
+
+inline uint32_t adat2audio(uint32_t x)
+{
+
+    uint32_t R = x&0xF;
+    R |= ( (x>>1) & 0xF0);    
+    R |= ( (x>>2) & 0xF00);   
+    R |= ( (x>>3) & 0xF000);    
+    R |= ( (x>>4) & 0xF0000);    
+    R |= ( (x>>5) & 0xF00000);
+
+    return R;    
+}
+
+inline uint32_t audio2adat(uint32_t x)
+{
+    uint32_t R = 0x02108421;
+    R |= ( (x << 1) & 0x1E );
+    R |= ( (x << 2) & 0x3c0 );
+    R |= ( (x << 3) & 0x7800 );
+    R |= ( (x << 4) & 0xf0000 );
+    R |= ( (x << 5) & 0x1E00000 );
+    R |= ( (x << 6) & 0x3c000000 );
+    return R;
+}
+
+inline void adat_enc(uint32_t* in, uint32_t* out)
+{
+    uint32_t R0, R1;
+    R0 = audio2adat(in[0]);
+    R1 = audio2adat(in[1]);
+    out[0] = R0 | (R1 << 30);
+    R0 = audio2adat(in[2]);
+    out[1] = (R0 << 28) | (R1 >> 2);
+    R1 = audio2adat(in[3]);
+    out[2] = (R0 >> 4) | (R1 << 26);
+    R0 = audio2adat(in[4]);
+    out[3] = (R0 << 24) | (R1 >> 6);
+    R1 = audio2adat(in[5]);
+    out[4] = (R0 >> 8) | (R1 << 22);
+    R0 = audio2adat(in[6]);
+    out[5] = (R0 << 20) | (R1 >> 10);
+    R1 = audio2adat(in[7]);
+    out[6] = (R0 >> 12) | (R1 << 18);    
+    out[7] = 0x08010000 | (R1 >> 14);
+}
+
+inline void adat_dec(uint32_t* in, uint32_t* out)
+{
+    uint32_t R0, R1;
+    R0 = in[0];
+    R1 = in[1];
+    out[0] = adat2audio(R0 >> 1);
+    out[1] = adat2audio( (R0 >> 31) | (R1 << 1) ); 
+    R0 = in[2];       
+    out[2] = adat2audio( (R1 >> 29) | (R0 << 3) );   
+    R1 = in[3];
+    out[3] = adat2audio( (R0 >> 27) | (R1 << 5) );        
+    R0 = in[4];       
+    out[4] = adat2audio( (R1 >> 25) | (R0 << 7) );   
+    R1 = in[5];
+    out[5] = adat2audio( (R0 >> 23) | (R1 << 9) );        
+    R0 = in[6];       
+    out[6] = adat2audio( (R1 >> 21) | (R0 << 11) );   
+    R1 = in[7];
+    out[7] = adat2audio( (R0 >> 19) | (R1 << 13) );        
+}
+
+
+inline void nrz_enc(uint32_t* in, uint32_t* out)
+{
+    static char last_bit = 0;
+    for (int i = 0; i < 8; i++)
+    {
+        register uint32_t R = 0;
+        uint32_t x = in[i]; 
+        unsigned char c;
+        for (int j = 0; j < 4; j++)
+        {
+            c = lut[(unsigned char)(x >> (j*8))];
+
+            c = last_bit ? ~c : c;
+           last_bit = c >> 7;
+            R = rorn(R | c, 8);
+        }
+        out[i] = R;
+    }   
+}
+
+inline void nrz_dec(uint32_t* in, uint32_t* out)
+{
+    static char dec_last_bit = 0;
+     for (int i = 0; i < 8; i++)
+    {
+        uint32_t x = in[i]; 
+        out[i] = x ^ ( (x << 1) | dec_last_bit );
+        dec_last_bit = x >> 31;
+    }      
+}
+
+
+
+
 int main() {
     
     Serial pc(USBTX, USBRX);
@@ -77,7 +182,7 @@
     
     for (int i = 0; i < 8; i++)    
     {
-        data[i] = 0x00842184;
+        data[i] = 0x00042184 + (i << 20);
     }
     
     uint32_t nframes = 480000; // 10s real time data
@@ -85,229 +190,21 @@
     t.start();
     for (int j = 0; j < nframes; j++)
     {
-        
-    register uint32_t r0 = 0x08010842; // user data (0), sync and ADAT '1's
-    register uint32_t r1 = rorn(data[7], 8);
-    register uint32_t R4 = 0x0000000F; // To write 4 audio bits at a time
-    unsigned char last_bit = 0;
-    
-    //ADAT frame encoding, starting from last word (sync)
-    // Pn comments enlight 'end of encoded word'
-    r0 |= (r1 & (R4 << 12));
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 7));
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 2));
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 >> 3 ));
-
-//P0
-    adat[7] = r0;
-    r0 = 0x10842108;
-    r0 |= (r1 & (R4 << 29));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 24));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 19));   
-
-    r1 = rorn(data[6], 6);
-    r0 |= (r1 & (R4 << 14));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 9));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 4));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 >> 1 ));   
-
-//P1
-    //ror1(&r1);
-    adat[6] = r0;
-    r0 = 0x42108421;
-    r0 |= (r1 & (R4 << 31));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 26));   
-
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 21));   
-
-    r1 = rorn(data[5], 4);
-    r0 |= (r1 & (R4 << 16));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 11));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 6)); 
-  
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 1));   
-
-    ror1(&r1);
-//P2
-    adat[5] = r0;
-    r0 = 0x08421084;
-    r0 |= (r1 & (R4 << 28));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 23));   
-
-    r1 = rorn(data[4], 2);
-    r0 |= (r1 & (R4 << 18));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 13));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 8));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 3));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 >> 2 ));   
-
-//P3
-    adat[4] = r0;
-    r0 = 0x21084210;
-    r0 |= (r1 & (R4 << 30));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 25));   
-
-
-     r1 = data[3];
-   r0 |= (r1 & (R4 << 20));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 15));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 10));   
-
-    ror1(&r1);
-    r0 |= (r1 & (R4 << 5));   
+        if (pb) // so that the compiler cannot preprocess anything
+        {
+            for (int i = 0; i < 8; i++)    
+            {
+                data[i] = (data[i] - i) &0xffffff;//make it recursive (makes really sure the compiler won't attempt to preprocess anything)
+            }
 
-    ror1(&r1);
-    r0 |= (r1 & (R4));   
-
-    ror1(&r1);
-//P4
-    adat[3] = r0;
-    
-    r0 = 0x84210842;
-    r0 |= (r1 & (R4 << 27));   
-    r1 = data[2] << 2;
-
-    r0 |= (r1 & (R4 << 22));   
-    ror1(&r1);
- 
-    r0 |= (r1 & (R4 << 17));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 12));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 7));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 2));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 >> 3));   
-
-//P5
-    adat[2] = r0;
-    
-    r0 = 0x10842108;
-    r0 |= (r1 & (R4 << 29));   
-    r1 = data[1] << 4;
-
-    r0 |= (r1 & (R4 << 24));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 19));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 14));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 9));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 4));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 >> 1));   
-    ror1(&r1);
-
-//P6
-    adat[1] = r0;
-    
-    r0 = 0x42108421;
-    r0 |= (r1 & (R4 << 31));   
-    r1 = data[0] << 6;
-
-    r0 |= (r1 & (R4 << 26));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 21));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 16));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 11));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 6));   
-    ror1(&r1);
-
-    r0 |= (r1 & (R4 << 1));   
-    ror1(&r1);
-
-//P7 -- final
-    adat[0] = r0;
-
-// NRZ encoding (8-bit LUT based) CPU intensive because recursive
-// -- decoding should be much faster (xor(D, (D>>1)) over 32-bit values)
-    for (int i = 0; i < 8; i++)
-    {
-        register uint32_t R = 0;
-        uint32_t x = adat[i]; 
-        unsigned char c;
-        for (int j = 0; j < 4; j++)
-        {
-            c = lut[(unsigned char)(x >> (j*8))];
-
-            c = last_bit ? ~c : c;
-            last_bit = c >> 7;
-            R = rorn(R | c, 8);
         }
-        adat_nrz[i] = R;
-    }   
-
-
-    if (pb) // so that the compiler cannot preprocess anything
-    {
-        for (int i = 0; i < 8; i++)    
-        {
-            data[i] = adat[i] &0xffffff;//make it recursive (makes really sure the compiler won't attempt to preprocess anything)
-        }
-
+        myled = pb;   
+          
+        adat_enc(data, adat);     
+        nrz_enc(adat, adat_nrz);
+        nrz_dec(adat_nrz, dec_nrz);
+        adat_dec(dec_nrz, adec);    
     }
-    myled = pb;   
-    }   
-    
     
     
     t.stop();
@@ -316,7 +213,7 @@
     gprintf("The time taken was %f seconds\n", toto.str());
        for (int i = 0; i < 8; i++)    
     {
-        printf("aata[%d] = %s\n", i, byte_to_binary(data[i]));
+        printf("data[%d] = %s\n", i, byte_to_binary(data[i]));
     }   
        for (int i = 0; i < 8; i++)    
     {
@@ -326,6 +223,19 @@
     {
         printf("adat_nrz[%d] = %s\n", i, byte_to_binary(adat_nrz[i]));
     }   
+        for (int i = 0; i < 8; i++)    
+    {
+        printf("dec_nrz[%d] = %s\n", i, byte_to_binary(dec_nrz[i]));
+    }   
+        for (int i = 0; i < 8; i++)    
+    {
+        printf("adec[%d] = %s\n", i, byte_to_binary(adec[i]));
+    }   
+    
+    
+    
+    
+    
 }