The BBC and Master Computer Public Domain Library

AA93 NOT

Submitted by Steve Fewell

Description:

Call the Evaluate value routine (&96B4) which will evaluate the next value at BASIC text
pointer B location, or the expression at that location if the value begins with an open bracket ("(")
and convert the result to an Integer value (or generate a Type mismatch error if the value was a String).

Starting at the Most significant byte of the IWA (&2D), EOR (exclusive-OR) each byte of the IWA with
&FF (&2D through to &2A). This will reverse the value in the IWA.
Set A to #&40 (meaning that the current value is an Integer) and exit.

Disassembly for the NOT routine