Here's where my memory really lets me down.

Off the top of my head, can't you emulate a NOT by simply subtracting the value from the value of "all-bits".

In other words, if the word size is 8 bits, NOT 128 would be the same as 255-128=127?

If its a DWORD, it would be 65535-128 and so-on.

You can calculate "all-bits" as (2^(WordSize+1))-1