Tony Duell wrote:
>
> >
> > Tony Duell wrote:
> > rganised, and doubtless some of the
> > > <snip,cut,rip>
> > > [1] The PE Digical may be one of the first hobbyist calculators
> > > (published 1972, all built from TTL chips), but it wasn't programmable.
> > > Stick it on the list if you like.
> >
> > Got more details???
>
> Sure, I've got all ten articles describing it. I think I posted rough
> descriptions of the contents of each article to Classiccmp a couple of
> years back.
>
> It was a 4 function desktop calculator. Display was those 7 segment
> filament displays (thin filaments forming the segments, mounted in an
> evacuated 'bulb'). About 10 digits, I think. It displayed -ve numbers in
> 9's compliment notation (!).
>
> The 'data path' was TTL ICs on plug-in cards. It was digit-serial, and
> did multiplication/division by shifting by digits and then repeated
> addition/subtraction for each digit.
>
> The control section was a diode matrix ROM on a large piece of stripboard
> in the bottom of the machine. Controlled by yet more TTL.
>
> 'PE', btw was the UK magazine 'Practical Electronics'.
>
> -tony
While I don't expect to find DTL,RTL or even TTL nowadays
you can still get the 7 segment filament displays.
http://www.sphere.bc.ca/test/nixies.html#catalog
--
Ben Franchuk --- Pre-historic Cpu's --
www.jetnet.ab.ca/users/bfranchuk/index.html
Received on Fri Nov 30 2001 - 17:26:33 GMT