External Oscillator on NS7520

I want the NS7520 to work at 55Mhz. I am using the External Oscillator with 55.296MHz on the NS7520.Now We have some problems,I would like to use the External Oscillator with 55.000MHz on NS7520. I don’t know which I need to use on NS7520. Please,Let me know.

Refer to the NS7520 development board schematics placed in the BOM. The dev. board makes use of an ext. oscillator set at 55MHz.