SP_MISC_INFO
reg = ad_read(&sc->sc_ad1848, SP_MISC_INFO);
ad_write(&sc->sc_ad1848, SP_MISC_INFO, reg | MODE2);
tmp = ad_read(sc, SP_MISC_INFO);
ad_write(sc, SP_MISC_INFO, (~tmp) & 0x0f);
if ((tmp & 0x0f) != ((tmp1 = ad_read(sc, SP_MISC_INFO)) & 0x0f)) {
ad_write(sc, SP_MISC_INFO, 0); /* Mode2 = disabled */
ad_write(sc, SP_MISC_INFO, MODE2); /* Set mode2, clear 0x80 */
tmp1 = ad_read(sc, SP_MISC_INFO);
ad_write(sc, SP_MISC_INFO, MODE3);