mp_read_radix
MP_CHECKOK(mp_read_radix(&irr, params->irr, 16));
MP_CHECKOK(mp_read_radix(&curvea, params->curvea, 16));
MP_CHECKOK(mp_read_radix(&curveb, params->curveb, 16));
MP_CHECKOK(mp_read_radix(&genx, params->genx, 16));
MP_CHECKOK(mp_read_radix(&geny, params->geny, 16));
MP_CHECKOK(mp_read_radix(&order, params->order, 16));
res = mp_read_radix(a, str, radix);
mp_err mp_read_radix(mp_int *mp, const char *str, int radix);