It might be worthwhile to take a look at the BX-24.  It has 400 bytes
of user RAM available after the O.S. is installed ... but it uses an
MCU from the dark side.
 - Nick -

Byron A Jeff wrote:
>
> >
> > Then riddle me this batman...how does the real basic stamp do it????????????
>
> OK riddler. The stamp restricted the number of variables.
>
> Check out the specs: http://www.parallaxinc.com/stamps/modules.htm
>
> The BS1 had 7 variables, the BS2 had 16. each 2 bytes but also byte addressible
> so that you can get 2 bytes out of every word.
>
> The chips they are based on, the 16C56 and 16C57, have 25 and 72 bytes of
> data ram respectively.
>
> They simply used what they had.
>
> But the stamp was designed 5-6 years ago when that was all they had available.
>
> Looking at Mchips offering right now, you have options including the 16C558
> and the 16C622 which offer 128 bytes of RAM, and at the 192 byte level the
> PIC16C6X series fills in nicely.
>
> But again just simply moving to a 16F84 or 16F84A (which is in spotty
> production right now) will bump you up to 68 bytes. And with the stamp
> apparently occupying 11 bytes for itself then you'd have room for 14 variables.
> It goes up to 58 for 128 bytes and 90 for 192 bytes.
>
> BAJ