ppb_rdtr
temp = ppb_rdtr(ppbus) & mask;
r = ppb_rdtr(bus);
*buffer = ppb_rdtr(bus);
*val = ppb_rdtr(ppbus);
sc->lastdata = ppb_rdtr(sc->ppbus);
i = ppb_rdtr(sc->ppbus);
i = ppb_rdtr(ppbus);