TCTRL_VLINS
sc->sc_tctrl &= ~(TCTRL_IPCSEN | TCTRL_TUCSEN | TCTRL_VLINS);
sc->sc_tctrl |= TCTRL_VLINS;
if (sc->sc_tctrl & (TCTRL_IPCSEN | TCTRL_TUCSEN | TCTRL_VLINS))
__SHIFTOUT(sc->sc_tctrl, TCTRL_VLINS));