Re: [NTLK] Soft reset that loses--everything?

From: Eric L. Strobel (fyzycyst_at_comcast.net)
Date: Wed May 08 2002 - 10:19:05 EDT


on 5/8/02 9:52 AM, Seth Hurwitz at shurwit1_at_jhmi.edu wrote:

>
>>>> fyzycyst_at_comcast.net 05/08/02 09:36AM >>>
>
> on 5/8/02 9:26 AM, Seth Hurwitz at shurwit1_at_jhmi.edu wrote:
>
>>> Could the added power drain of the actively used modem have dropped the
>>> power low enough during the reset to cause this??
>>
>> (clutching at straws, obviously)
>>
>> My (limited) understanding is that low power level should have nothing to do
>> with a brain wipe (e.g. Newtons hold data w/o power).
>>
>> That's why I said I was clutching at straws. However, circuits sometimes do
>> very funny things when under higher than normal power drain while at low
>> power levels (and this was also in a transitory environment, i.e. a reset).
>> Rapid changes in voltage can do odd things to digital circuitry. In this
>> case it would've had to somehow trigger the deep reset. I have no idea how
>> isolated the logic for that is from the logic for a normal reset and if a
>> voltage transient could flip you over from one to the other. Given the
>> robust nature of the Newt, one would like to think it was at least *that*
>> fault tolerant, but it was built by human beings...
>
> Eric, this is really interesting. I was wondering something like this
> myself but you explain it a whole lot better than I could. What *is* the
> difference between soft and hard resets? I mean, is one A and the other
> B, or is one A and the other AA (or A times 2), if you know what I mean.
> :)
>

Gonna take someone MUCH more Newt-savvy than I am to answer that one.
(Unless it's tucked away somewhere in the FAQ and nobody's remembered...)

But, speculating a bit, my guess is that the reset features cause execution
of some embedded digital program and, oversimplifying a bit, one changes a
voltage on an input to prompt such an action. The question is then: are
there common inputs between the soft and hard resets, and is there common
logic between the two? If yes to either parts of that question, then it MAY
be reasonable to hypothesize a transient voltage as the culprit.

It's going to take a Newt-hardware guru (of which there's a few on this
list) to say whether this is bunk or not.

- Eric.

- Eric.

-- 

Eric Strobel (fyzycyst_at_NOSPAM^mailaps.org)

===================================================================== The odds are greatly against you being immensely smarter than everyone else in the field. If your analysis says your terminal velocity is twice the speed of light, you may have invented warp drive, but the chances are a lot better that you've screwed up. =====================================================================

-- Read the List FAQ/Etiquette: http://www.newtontalk.net/faq.html Read the Newton FAQ: http://www.guns-media.com/mirrors/newton/faq/ This is the NewtonTalk mailing list - http://www.newtontalk.net



This archive was generated by hypermail 2.1.2 : Wed Jun 12 2002 - 20:02:07 EDT