The serially connected memory is connected to {HEAD ~ a two wire output port} of {TAIL ~ the dedicated diagnostic data port} 
The serially connected memory is connected to { HEAD ~ a two wire output port } of { TAIL ~ the dedicated diagnostic data port }
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL