While I agree that as long as things can be restored it's not a real
problem, I'm surprised that not more people consider it a serious overkill.
We're talking about putting in a rather complex computer to generate a
baud rate. Are people really that handicapped when it comes to building
hardware nowadays? Are people aware how easy baud generators are?
We're essentially talking about a clock, which can be found as a
component (various oscillators), and then dividing it. There used to be
chips around which did that part, and I would expect it to not be that
hard to find some if you looked today. Many UARTs even comes with a
clock divider built in.
And that is it. When I build various Z80 systems, I usually had a Z80
CTC included, which I used for generating the baud rates.
Johnny
On 2015-06-15 02:52, Joe Lenox wrote:
I also think it is in the spirit of the computer -
using what is available
to fix a problem at hand. I think the arduino was overkill when an attiny
(smaller, easier to hide) would probably serve just as well.
If you have the ttl logic bits lying around and know how to use them, fine.
Still would probably need debugging.
On Jun 14, 2015 2:41 PM, "Simon Claessen" <simski at dds.nl> wrote:
> as long as it is done in a way that it can be restored to its original, i
> have no problems in using newer technology in older machines. we have a
> alix sbc build into our tek 4002a for demonstrational purpouses, all done
> without damaging or altering the original machine.
>
> On 14-06-15 17:25, tony duell wrote:
>
>>
>> The ripple on the power supplies is still going lower as we put more run
>>> time on the system. The power supplies are now within spec.
>>>
>>
>> Capacitors reforming naturally?
>>
>> Warren made an Arduino based programmable baud rate generator that works
>>> for both serial ports. After some debugging, it works nicely.
>>>
>>
>> I am sorry, but I find that obscene!. To use more components than the
>> rest of the machine
>> (probably) just for the baud rate clock is ridiculous. IMHO if you are
>> going to modify a
>> vintage machine, particularly one as rare as a PDP12, you should use the
>> components
>> that were available at the time. It's not as if a programmable buad rate
>> generator is hard
>> to make from TTL either. In fact given the Arduino thing needed 'some
>> debugging' it might
>> well have taken less time to do it in hardware.
>>
>> -tony
>>
>>
> --
> Met vriendelijke Groet,
>
> Simon Claessen
> drukknop.nl
>
--
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|| on a psychedelic trip
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