an example can be found on AMOSPro_Examples:Examples/H-5/Help_55.AMOS
Tests a single bit in your number and returns a value of -1 (true) if it's a one, or 0 (False) if it's a zero.
Checks a bit in your selected variable. position holds a bit number ranging from 0 to 31.
Evaluates the expression, and tests the bit at the resulting memory ADDRESS. The bit position is restricted to values from 0 to 7.