70's computers

[allison]

On 10/25/2018 01:28 PM, ben via cctalk wrote:
> On 10/24/2018 9:00 PM, Jon Elson wrote:
>> On 10/24/2018 01:11 PM, ben via cctalk wrote:
>>> On 10/24/2018 10:31 AM, Marc Howard via cctalk wrote:
>>>> You know that since you mentioned possibly using CMOS 22V10's why
>>>> not just
>>>> build a board around AMD 29XX bit slice parts.  They actually predate
>>>> 22V10's by quite a bit and you can pretty much implement what every
>>>> you
>>>> want to without rewiring.
>>>>
>>>> Marc
>>>
>>> * LOW POWER and REPROGRAMABLE * reglar 22V10's are 100 ma per chip,
>>> and I can buy them online. I have 5 2901's but I can only find them
>>> on ebay now. If I design a register based machine I have them, other
>>> wise
>>> TTL is better for odd sized word lengths.
>>> Ben.
>>>
>>>
>>>
>> Well, I built a 2903 + 2910 32-bit microcoded machine in 1982 or so. 
>> See
>> http://pico-systems.com/stories/1982.html
>> for gory details.  But, today, it would make WAY more sense to do it
>> with FPGAs.  Want to try an experiment?  Don't get out the wire-wrap
>> gun or soldering iron, make a copy of the FPGA files and edit away.
>> If it doesn't work, you don't have to undo the wiring changes! Also,
>> the FPGA version might be as much as 10 times faster.
>
> I just orderd 4 2901's off ebay, So I do plan to build something up to
> 32 bits.

Likely make a fortune off my stockpile of 2901s. 

Building machine from the earth up is not that hard, software to make
them useful is a big deal.

> I have a DE1 FPGA setup for proto typing, but free pcb board layout
> programs all seem to suck for me. There is nothing for doing things
> like switches or card edge foot prints, but a gizzion and one surface
> mount that common people never use.
>
The problem is you need to hunt down the libraries or use a tool that
has libraries.  Kicad and Eagle are
work for me.

Once you have libraries that have those doing it become easy.  IF not
draw them!
 
Allison
>
>
>> Jon
>>
>