The navigation map on my 1490T suddenly changed. Probably due to something I may have done inadvertently, only I don't know what it was and how to reset the condition.

Instead of displaying a map across the whole screed, the screen was split by a vertical line into a left hand map occupying 2/3 of the screen. The right hand side part consists of 4 rectangles arranged vertically, displaying, from top to bottom: "arrive in, arrive, elevation and speed".

How do I annul this change and switch back to the original display?