I have a Tomtom XL n14644. It ws working fine but then I turned it on and tried to find and address and it turned itself off. When it restarted I got the drum and now all I get is a black screen with white lettering describing all the tech data about the unit(hardware type, subID, bootloader,etc.). It constanly tries to restart, durms and tomtom logo then goes back to the tech data page. Pushing the power button does nothing. I downloaded tomtom home and tried to hook it up tomy computer but it doesn't see it. How do I get it back?