Pomogite. Srochno

Y menya est' seldyushaya procedure gde pervoe alphanumeric value perevoditcya v numeric.
alphanumeric value vsegda pervaya poziziya.
Kak mne izmenit cho bu moglo sypportat' takoe znachenie kak '3AF'? Poslednie alphanumeric.

DBCHAR Modifier[4];
int convert_char_modifier(char *Modifier, char *NewModifier)
{ char NewMod2[8];
char Tempcrap[8];
char Tempcrap1[8];
memset(NewMod2,0x00,sizeof(NewMod2));
memset(Tempcrap,0x00,sizeof(Tempcrap));
memset(Tempcrap1,0x00,sizeof(Tempcrap1));
sprintf(NewModifier, "%02d", Modifier[0] - 64);
sprintf(Tempcrap1, "%d", Modifier[1] - 48);
strcpy(Tempcrap, Tempcrap1);
sprintf(Tempcrap1, "%d", Modifier[2] - 48);
strcat(Tempcrap, Tempcrap1);
sprintf(NewMod2, "%03s", Tempcrap);
strcat(NewModifier, NewMod2);
return(0);
}