Optima xm keypad not responding?

had a power cut and alarm sounded, could not reset, got power back and alarm was still sounding in low volume, eventualy went off but blue strobe remained flashing. removed lead from battery and strobe eventualy went off, now restored battery leads and mains power but still cannot set or reset anything, No response to any keypad pressing at all, is as if keypad is dead. All zone and power lamps are showing on.
Any ideas?