NFRAMES
sc->rftail = (sc->rftail + 1) % NFRAMES;
sc->rfhead = (sc->rfhead + 1) % NFRAMES;
for (i = 0; i < NFRAMES; i++)
for (i = 0; i < NFRAMES; i++)
MK_16(MEM, sc->rframes[(i + 1) % NFRAMES]);
sc->rframes[NFRAMES - 1]->ie_fd_last |= IE_FD_LAST;
sc->rftail = NFRAMES - 1;
volatile struct ie_recv_frame_desc *rframes[NFRAMES];
i = (i + 1) % NFRAMES;