Re: A83: Re: dead calc!!!


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Re: A83: Re: dead calc!!!




Well, there may be something to that - Most systems have some sort of
supervisory
circuit to prevent the processor from starting on power-up, till the
voltage
reachs a value which allows reliable system operation. Typically the uP
is held
in a hardware reset, so it's drawing current - Blipping the power faster
than
the time constant of the supervisory circuit might allow the uP to pull
down
the RAM retention current enough to scramble RAM and allow a cold start.

Just a guess, but computers do weird things when you start diddling
power.

Regards, Jack


Linus Akesson wrote:
> Yes, I was being sarcastic because this guy said it helped resetting the calc
> by rotating the batteries, because they turned off the voltage for short
> periods.
 
> >The calcs memory is CMOS static RAM - The current required
> >for memory retention is a few microamps, perhaps even less.
> >This current can be supplied by the filtering, decoupling,
> >and distributed capacitance in the circuit for quite a while.

> >> Then how do you explain that I can remove all my (the calculator's)
> >batteries
> >> for some seconds, then replace them, and then have all memory intact?


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