bsv.c

   1 typedef unsigned char u8;
   2
   3 u8 i0, i1, i2; //MEM
   4 u8 acc; //ACC
   5
   6 u8 notes[] = {
   7         0x84, 0x9d, 0xb0, 0x69, 0x9d, 0x84, 0x69, 0x58,
   8         0x75, 0x8c, 0xb0, 0x69, 0x8c, 0x75, 0x69, 0x58
   9 };
  10
  11 void g(u8 t){
  12         u8 notes_ix = t & 0x7;
  13         if(3&i2)
  14                 notes_ix += 8;
  15         u8 result = ((i1<<8|i0)*notes[notes_ix])>>8;  // keep hi byte
  16         acc = result;
  17 }
  18 void main(void){
  19         i0 = i1 = i2 = 0;
  20         for(;;) {
  21                 u8 sample;
  22                 u8 n = i2<<2 | i1>>6;
  23                 u8 s = i2>>1;
  24
  25                 g(n);
  26                 acc >>= 4;
  27                 acc &= 1;
  28                 sample = acc;
  29
  30                 { u8 tmp;
  31                   tmp = i2<<3 | i1>>5;
  32                   tmp ^= n;
  33                 g(tmp);
  34                 acc >>= 2;
  35                 acc &= s;
  36                 acc &= 3;
  37                 sample += acc;
  38                 } //tmp
  39
  40                 { u8 tmp1 = s/3;
  41                   u8 tmp2;
  42                   tmp2 = (i2<<5|i1>>3)%3;
  43                   tmp2 += n;
  44                 g(tmp2);
  45                 acc >>= 2;
  46                 acc &= tmp1;
  47                 acc &= 3;
  48                 sample += acc;
  49                 } //tmp1, tmp2
  50
  51                 { u8 tmp1 = s/5;
  52                   u8 tmp2 = n;
  53                   { u8 tmp3 = (i2<<6|i1>>2)%3;
  54                     tmp2 -= tmp3;
  55                   } // tmp3
  56                   tmp2 += 8;
  57                 g(tmp2);
  58                 acc >>= 1;
  59                 acc &= tmp1;
  60                 acc &= 3;
  61                 sample += acc;
  62                 } //tmp1, tmp2
  63
  64                 putchar(sample<<4);
  65
  66                 i0++;
  67                 i1 += !i0;
  68                 i2 += !i1 && !i0;
  69         }
  70 }