conditional data validation

I have 2 data validation listboxes
I want the 2nd listbox to be populated with certain values conditional upon user's choice in the 1st listbox.

i.e., if i choose x in the 1st listbox, then there are certain values in the
2nd listbox, if i choose y in the 1st listbox, then there are different values in the 2nd listbox

I know I can do this with naming ranges of cells, and the function INDIRECT
My problem is that I can’t name a range of cells with a numeric value and this is required in my case.

This what I’m trying to do:
A1 has 3 options (listbox)– 0,1,H
B1 depends on AI:
If A1 = 0, then B1 has 3 options - A,B,C
if A1 = 1, then B1 has 3 options - D,E,F
If A1 = H then B1 has 3 options – G,H,I

Any ideas?

thanks so much!
works like a charm...