I would think that the Alpha microcessor is pretty basic and looking for
simple analog inputs.
Much like an automotive processor. I had a built up LT1/4L60E Corvette combo
in a 38 Chevy coupe and the tranny began slipping. A rebuild was $1800. A
little bit of monitoring with a DVM ascertained what voltages the processor
was looking for to cause the shift solenoids to actuate. Then it was simply
a trip to the junkyard for a good non electronic 700R4 tranny and a couple
of resistors across the old harness connector to fake out the processor and
I was back in business for $250 with sharper shifting to boot.
Sometimes it pays to think out of the box.
----- Original Message -----
From: "Tom W8JI" <firstname.lastname@example.org>
To: <email@example.com>; "'Jim Brown'" <firstname.lastname@example.org>;
Sent: Wednesday, July 18, 2007 1:02 PM
Subject: Re: [Amps] ALPHAs and momentary power outages
>> I'm glad someone was paying attention. It would be hard to
>> reprogram the
>> microprocessor, but it would be easy to patch the timer
>> value on the fly, as
>> needed. You just have to get the address(s) and meaning of
>> the value(s) from
> My bet is the timer has a reset line or line that monitors
> power down. It may even just be when the power to the
> microprocessor is removed, the CPU restarts.
> The simplest approach would be to fool the system into not
> knowing the power ever went down. You could do that with a
> battery and R/C timer, a large electrolytic and a few
> diodes, or any other number of ways.
> Maintaining the entire power line and HV supply is probably
> not even necessary. I would however restrict the hang time
> to several seconds and no longer, and make sure the step
> start recycled.
> 73 Tom
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