Hello AF330,
First of all, you need to know there are difference between jet engine manufacturers and what they use as their main thrust control parameters. Rolls Royce and Pratt & Whitney use EPR to control thrust. GE uses N1 to control thrust. N1 is fan speed. GE believes fan speed is a better overall indicator of true thrust as it takes into account the air that bypasses the core engine. So if the A-320 is powered by a CFM56 engine (partly a GE product), it will have the N1 mode button and the EPR button will not be present. Some of the A-320 have IAE engines that are a product of Pratt & Whitney, Rolls Royce and others that use EPR as the measure to control thrust. Other than the N1, EPR, your understanding is basically correct.
