Hi there, welcome to the Text Blaze community 
Check out this post: Quicktip - Capitalizing text
Here's the example (below) from the post that I believe answers your question.
One thing to note is that the formulas use the form name of the text field. Please let me know if you have any questions!
{formtext: name=text; default=the QUICK BrowN fOx juMPed Over the LAZY doGs}
No change: {=text}
All uppercase: {=upper(text)}
All lowercase: {=lower(text)}
Title case: {=proper(text)}