On Mon, 4 Oct 1999, Jukka Marin wrote:

> On Mon, Oct 04, 1999 at 01:55:30PM -0400, Dave McGuire wrote:
> > >> Indeed what it all boils down to is that a logic "1" value is
> > >> represented by a voltage between +3 and +25 VDC, and a logic "0"
> > >> value is represented by a voltage between -3 and -25 VDC.
> > 
> >   Umm, I believe those levels are inverted.  A "1" is represented by the
> > negative voltage, and a "0" was represented by the positive.  That stuck in my
> > mind from way back because it's...well, inverted. :-)
> 
> That's correct.
> 

Just use the phrase "mark one off negative"...its a quick way of
remembering it.