Duplicate web controls on a form

Hi,
Apologies for this question, I'm sure that it very basic....
I have a form and I want to put two controls that display a drop-down of currency codes.  It is to calculate an amount from a 'from' and a 'to' currency.
We have a generic Currency User Control that is suitable, but I want to run a slightly different bit of SQL to populate the dropdown when the form loads.
Can anyone provide me with an example and an explanation of how to do it?
Thanks
Paul