Grab your copy of my A320 Alpha Call Ups 

Free downloadable pdf from an industry expert..

Alpha (or Alphanumeric) Call Ups are aircraft system parameters which are displayed live as they happen, for the benefit of technical staff to observe data and repair faults.  This data could be anything, from Aileron Positions (changes through movement), to Engine Vibrations, to how much Pressure is in an Air Bleed Duct when the Valve to that Duct is fully open, or throughout its transition till it is closed.

This list is what a A320 Maintenance Engineer has “for ease of reference” when looking for the specific code for the specific detail.