EMU_CHAN_IFATN
emu_wrptr(sc, ch, EMU_CHAN_IFATN, 0xffff);
emu_wrptr(sc, v->vnum, EMU_CHAN_IFATN, 0xff00);
emu_wrptr(sc, v->vnum, EMU_CHAN_IFATN, 0xffff);
emu_wrptr(sc, v->vnum, EMU_CHAN_IFATN, 0xff00);
emu_wrptr(sc, v->vnum, EMU_CHAN_IFATN, 0xffff);
emu_wrptr(sc, ch, EMU_CHAN_IFATN, 0xffff);
#define EMU_CHAN_IFATN_FILTERCUTOFF EMU_MKSUBREG(8, 8, EMU_CHAN_IFATN)
#define EMU_CHAN_IFATN_ATTENUATION EMU_MKSUBREG(8, 0, EMU_CHAN_IFATN)