Re: A83: Re: dead calc!!!
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Re: A83: Re: dead calc!!!
Yeah, well, since he claims it _works_, then there's probably some
explanation. Might be yours, might be something supernatural... =) Whatever.
Linus
On 13-Sep-98, goflo@pacbell.net wrote:
>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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