sc_drive
struct fd_softc *ofd = fdc->sc_fd[fd->sc_drive ^ 1];
FDC_WRFIFO(fdc, fd->sc_drive); /* drive number */
FDC_WRFIFO(fdc, fd->sc_drive); /* drive number */
fd->sc_drive, fd->sc_cylin, head, sec, nblks);
FDC_WRFIFO(fdc, (head << 2) | fd->sc_drive);
FDC_WRFIFO(fdc, (head << 2) | fd->sc_drive);
FDC_WRFIFO(fdc, fd->sc_drive);
int sc_drive; /* physical unit number */
fd->sc_drive = drive;
status |= fd->sc_drive;
int sc_drive; /* physical unit number */
fd->sc_drive = drive;
status = fd->sc_drive;
fdc->sc_link.fdlink.sc_fd[fd->sc_drive ^ 1];
out_fdc(iot, ioh, fd->sc_drive); /* drive number */
read ? "read" : "write", fd->sc_drive, fd->sc_cylin, head,
out_fdc(iot, ioh, (head << 2) | fd->sc_drive);
out_fdc(iot, ioh, (head << 2) | fd->sc_drive);
out_fdc(iot, ioh, fd->sc_drive);