(NRZI) A reCording method used for 9-traCk {magnetiC tapes} (200 and 800 BPI) where a zero is represented by a Change in the signal and a one by no Change. NRZI is also used extensively in SDLCCommuniCations. VTAM has a parameter NRZI=YES|NO. Compare Phase EnCoded, GCR. (1999-01-11)