VRC2_EXGPDIR
regs[1] = read_4(sc, VRC2_EXGPDIR);
sc->sc_intr_mask = (~read_4(sc, VRC2_EXGPDIR) & 0xffffff);
if (read_4(sc, VRC2_EXGPDIR) & mask) {
reg = read_4(sc, VRC2_EXGPDIR);
write_4(sc, VRC2_EXGPDIR, reg);