stepping machanism of Apple Disk ][ drive (was Re: Heatkit 51/4

From: Dwight Elvey <elvey_at_hal.com>
Date: Mon Apr 12 15:42:53 1999

allisonp_at_world.std.com wrote:
>
> > Talking of things like that, I seem to remember that Signetics sold a
> > demonstration board based on the 3001/3002 bitslice chips that ran 8080
> > code a lot faster than a real 8080.
>
> Those were indeed fast (about 4-5x) and the firmare was extensable, I'd
> love to find one.
>
> > Then there was the Tektronix 'almost 6800' used in the 4052, etc. It was
> > a board of 2901's, etc and ran an instruction set that was almost upwards
> > compatible with the 6800 used in the 4051 (IIRC the DAA instruction was
>
> The moto 6800 was protoed using 2901s. It would only need two.
>
> Allison
>

Hi
 Most use programmable parts to make specialized processors
now days. When I was with Intel, we had a controller card
that used 3001's as the control processor. All I remember
was that I wish they'd used the 2900 family sequencer instead
of the goofy thing Intel had. Programming was almost impossible
and just trying to follow someone elses program was a
major effort. It made it real difficult for someone to
copy your code without being obvious about though.
Dwight
Received on Mon Apr 12 1999 - 15:42:53 BST