I have a Blaupunkt Car Radio/Cassette that was factory fitted to my
Nissan Micra (1993).

It has locked itself up and won't let me enter the code - it didn't
even allow the 3 attempts before it locked up and waiting for an hour
(as suggested by Blaupunkt) doesn't work either).

Any ideas about how ot unlock it apart from completely replaceing the
EPROM?

Thanks

Ben