Dave, Here are links to the user manuals for the PCI-MIO-16E-1 and the BNC-2110. These manuals should help you understand the signal connections a little better:
http://digital.ni.com/manuals.nsf/websearch/06F1C9FB0D0BA5C286256C010057461B?OpenDocument&node=132100_US http://digital.ni.com/manuals.nsf/websearch/7A862014CCE0CA0486256D3B005CE8DE?OpenDocument&node=132100_US Regards, Bill B.