What do decimal/alphanumeric suffixes after a slash mean in a schematic cross-reference?
From Eagle help file 'Editor commands - LABEL':-


  Cross-reference labels
  
  If the optional keyword XREF is given, the label will be a
  "cross-reference" label. Cross-reference labels can be used in
  multi-sheet schematics to indicate the next sheet a particular net
  appears on...
  
  The format in which a cross-reference label is displayed can be
  controlled through the "Xref label format" string, which is defined in
  the "Options/Set/Misc" dialog, or with the SET command. The following
  placeholders are defined, and can be used in any order: 
  
  %F enables drawing a flag border around the label
  
  %N the name of the net
  
  %S the next sheet number
  
  %C the column on the next sheet
  
  %R the row on the next sheet
  
  The default format string is "%F%N/%S.%C%R".
  
  The column and row values only work if there is a frame on the next sheet on which the net appears... If the net appears only on the current sheet, no cross-reference is shown


So TDI/3.2D means net TDI goes to sheet 3 column 2 row D.