ENRTE CRUISE; FLT CTL UNITS (FCU'S) 1 AND 2 FAULTED; CAUSING LOSS OF CRT DISPLAYS AS WELL AS AUTOPLT AND AUTOTHROTTLES. MOMENTARY COCKPIT CONFUSION WITH AURAL AND VISUAL WARNINGS ON ECAM. ACFT STARTED CLB; AND BEFORE THE PLT CORRECTED; HAD GONE ABOVE ASSIGNED ALT BY 400 FT.

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STABLE CRUISE FLT; AUTOPLT CONNECTED. WX NOT A FACTOR. AUTOPLT DISCONNECTED; AUTOTHROTTLES DISCONNECTED; FLT DIRECTORS DISAPPEARED; AND ALL CRT DISPLAYS EITHER FROZE OR CHANGED. SEVERAL WARNINGS SUDDENLY SOUNDED AND APPEARED. EXTREME CONFUSION EXISTED FOR SEVERAL SECONDS. ECAM MESSAGE APPEARED (AIRBUS 320) 'FCU 1 AND 2 FAULT.' PNF BEGAN ECAM ACTION; PF RETURNED ACFT FROM 37200 FT MSL TO FL370. CTR CALLED TO INFORM US OF ALT DEV TO 37400 FT MSL. THE PROB: FLT CTL UNIT; CHANNEL 1 HAD FAILED; AND TOOK CHANNEL 2 WITH IT. RESULT: GLASS COCKPIT WITH JURASSIC JET CAPABILITIES. ABLE TO DO RAW DATA CAT 1 APCH. NO AUTOPLT; FLT DATA OR ALT. THE ALTDEV WAS TRIGGERED BY THE BAROMETRIC ALTIMETER; THE STANDBY ALTIMETER. THE ALT WARNING (MODE C) DEFAULTED TO THE STANDBY ALT UPON THE FCU FAILURE. OUR STANDBY ALT DIFFERED FROM OTHER ALTIMETERS BY 180 TO 200 FT DURING THIS SEGMENT. RECOMMENDATION: CHANGE ECAM MESSAGE FROM 'CHK BARO REF' TO 'CHK BARO ALTIMETER' OR 'CHK STANDBY ALTIMETER.' ALSO; ELIMINATE SOME OF THE AURAL WARNINGS; MUCH TOO CONFUSING.