How to make a Dynamic Text Field READ-ONLY

Hi all

This might sound a simple question, but I could not find an answer for it. Basically I have a [COLOR=red]Dynamic Text Field[/COLOR], whose value should be derived from a database, BUT should not be allowed to be modified by a user!
The same issue applies to an [COLOR=red]Input Field[/COLOR].

Any hints?
Thanks
[COLOR=red]Hagop [/COLOR]