SBT_REG_DAT
error = sdmmc_io_write_multi_1(sc->sc_sf, SBT_REG_DAT, hdr, 3);
error = sdmmc_io_write_multi_1(sc->sc_sf, SBT_REG_DAT, buf, len);
error = sdmmc_io_read_multi_1(sc->sc_sf, SBT_REG_DAT, hdr, 3);
error = sdmmc_io_read_multi_1(sc->sc_sf, SBT_REG_DAT, buf, len);