@pernia @Inginsub @qint I don't know what ideas you want. Just do a 32-bit multiply, this yields a 64-bit result. You need to shift it right by 16 bits to correct the fractional part. There must be a recipe book for fixed-point math somewhere.

> each number with a whole part and fractional part in their own word

That would be fixed-point, not floating-point.

> xor ax, ax
> xor dx, dx
> mov ax, whole0

pernis