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