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

From: allisonp_at_world.std.com <(allisonp_at_world.std.com)>
Date: Mon Apr 12 15:19:10 1999

> 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
Received on Mon Apr 12 1999 - 15:19:10 BST