PPB_BYTE
ppb_set_mode(bus, PPB_BYTE);
case PPB_BYTE:
case PPB_BYTE:
if ((error = ppb_1284_negotiate(bus, PPB_BYTE, PPB_REQUEST_ID)))
error = spp_1284_read(bus, PPB_BYTE, buffer, max, read);
case PPB_BYTE:
ppi->ppi_mode = PPB_BYTE, 0)))
ppb_peripheral_negotiate(ppbus, PPB_BYTE, 0);