Hi,
It looks to me like you have a two digit BCD value packed into one byte, is that correct?

I'm sure there are better and more clever ways of doing it but this seems to do what I think it is you're asking about:
Code:
If (CheckPanelDigit & 15) < 10 AND (CheckPanelDigit & 240) >> 4 < 10 then
'...more code here
Try it out and see if it does what you want.

/Henrik.