To isolate only one bit (or a set of bits) and exclude all the rest, AND a mask with the value. What you have left is only the bits you asked for.
Also if you don't know what bit you're looking for, put $1 into a variable, then use:
Local a:Int=$1 Shl BitNumber
to move that bit into the bit that you want (numbered from 0). Then that gives you the mask with which you can isolate the bit in whatever value you have. Then you can do:
Value=(Value & ($1 Shl BitNumber)) Shr BitNumber
if you want to put that bit right justified in the variable, so you can do math on it
Also if you don't know what bit you're looking for, put $1 into a variable, then use:
Local a:Int=$1 Shl BitNumber
to move that bit into the bit that you want (numbered from 0). Then that gives you the mask with which you can isolate the bit in whatever value you have. Then you can do:
Value=(Value & ($1 Shl BitNumber)) Shr BitNumber
if you want to put that bit right justified in the variable, so you can do math on it