A communications apparatus comprising a plurality of communication devices each having a plurality of ports and a data bus interconnecting {HEAD ~ the plurality} of {TAIL ~ units}, wherein each device is provided with means enabling the device to detect automatically its position on the data bus 
A communications apparatus comprising a plurality of communication devices each having a plurality of ports and a data bus interconnecting { HEAD ~ the plurality } of { TAIL ~ units } , wherein each device is provided with means enabling the device to detect automatically its position on the data bus
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH