I have recently started using the MAD decoder. My requirement is to use the MP3 library for the ARM 32 bit processor environement. I have compiled the library with the option FPM_ARM selected (I have modified the MACRO functions for my compiler support keeping the assembly instructions the same). But the audio output was not clear at all. Then I had selected FPM_DEFAULT. With that I am able to hear a feeble (but with noise) audio.

/**** mad_f_mul ****/

#define FPM_ARM

# define SIZEOF_INT 4
# define SIZEOF_LONG 4
# define SIZEOF_LONG_LONG 8

# define MAD_F_FRACBITS 28

#define MAD_F_SCALEBITS MAD_F_FRACBITS

static mad_fixed_t mad_f_mul(mad_fixed_t x,mad_fixed_t y)
{
mad_fixed_t result;
mad_fixed64hi_t hi;
mad_fixed64lo_t lo;

_asm(-1000,"
   smull %0,%1,%3,%4
   movs %0,lsr(%0,%5)
   adc %2,%0,lsl(%1,%6)
  ",
  __reg_gen(__obj_modify(lo)),
  __reg_gen(__obj_modify(hi)),
  __reg_gen(__obj_assign(result)),
  __reg_gen(x),
  __reg_gen(y),
  MAD_F_SCALEBITS,
  (32 - MAD_F_SCALEBITS)
  );

return result;
}

/****Ends****/

I like to know if I am missing something?

Thanks

Balaji Shanmugam