EXCA_REG_INDEX
bus_space_write_1(sc->bst, sc->bsh, EXCA_REG_INDEX, reg + sc->offset);
bus_space_write_1(sc->bst, sc->bsh, EXCA_REG_INDEX, reg + sc->offset);
bus_space_write_1(exca->bst, exca->bsh, EXCA_REG_INDEX,
bus_space_write_1(exca->bst, exca->bsh, EXCA_REG_INDEX,