[greenbit]

I wondered this as well.

Thinking about it, if all you have is "invert some (N>1?) bits somewhere and jump to somewhere" .. I could see maybe it might work if you use self modifying code and there's really a 2nd instruction that is a no-op? Seems like it might work more like a cellular automata?

Of course, one could just go look at the documentation, but where's the fun in that?

[int_19h]

You don't need a no-op; you can always just flip a bit you don't care about (e.g. reserve a word just for that) and then jump to next instruction.