ToUpper() ?

[jebem]

How about this:

- Define an array variable like Table(i) with the required dimension, for instance, 256 entries (or any other value, depending on the character table size to use).
- Initialize each array position with the required Uppercase value.
- As input, use the lowercase character binary weight as an index to the Table(i) array list and get the corresponding uppercase value.

I didn't try to implement this kind of algorithm in the Prime myself, though.