How can i fix my Accenta 6 alarm system?

Hi There, I have an Accenta 6 alarm system fitted to my home and has not missed a beat since it was fitted a number of years ago, however, we had a power cut in the middle of the night, and for some reason the control keypad has stopped working with no illuminated day or power lights and no illuminated keypad buttons, i still have the red power indicator light on the main control box working and have checked the fuse, also the ext bell box is constantly flashing a bright white light which is now annoying the neighbours at night! does anyone have any clues please? regards Mark.