SEL_VOLTAGE_STEP
cur_uvol = __SHIFTOUT(oval, SEL_VOLTAGE) * SEL_VOLTAGE_STEP +
val = SEL_GO | ((min_uvol - SEL_VOLTAGE_BASE) / SEL_VOLTAGE_STEP);
delay((abs(cur_uvol - min_uvol) / SEL_VOLTAGE_STEP) * sc->sc_ramp_delay);
*puvol = __SHIFTOUT(val, SEL_VOLTAGE) * SEL_VOLTAGE_STEP +