Machine reset after drop
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Machine reset after drop
And by "drop", I mean a physical drop, face down on the pavement (because I'm a bonehead). It was still in the case, so it appears to be perfectly fine. However the sudden G-forces caused the device to reset, thus loading the most recent state saved in flash, which was about 2 days old. The date and time were still correct, which makes me think the SRAM retained its contents. Perhaps the reset routine could be enhanced to include something like the dreaded HP 48 "Try to recover memory?" and just run the current program with whatever happens to be in memory? Maybe with a few basic consistency checks to detect major corruption.
Re: Machine reset after drop
I can only imagine "the sudden G-forces" causing an interrupt in voltage supply due to a short loss of contact - which in turn caused a reset. Beyond this, the effect of gravity on electrons should be negligible.Dave Britten wrote: ↑Mon Oct 22, 2018 2:04 pmHowever the sudden G-forces caused the device to reset...
Edited to correct an error in a foreign language.
Last edited by Walter on Mon Oct 22, 2018 4:59 pm, edited 1 time in total.
WP43 SN00000, 34S, and 31S for obvious reasons; HP-35, 45, ..., 35S, 15CE, DM16L S/N# 00093, DM42β SN:00041
Re: Machine reset after drop
I only use my calculators when standing over thick carpet.
DM15L, S/N 00548. DM42, SN: 00159. DM41X, SN: 00973. DM32, SN 00054.
Re: Machine reset after drop
To kill them by ESD?
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Massimo
ajcaton
-+×÷ left is right and right is wrong Casted in gold
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Re: Machine reset after drop
That was my assumption too. The battery probably bounced away from the contacts for just a moment. Which makes me wonder if I could solder a small 3V cap across the two battery lines to smooth out such brief losses of power. If I did, I would just take it on faith that it works, rather than repeatedly dropping the calculator on pavement to confirm.Walter wrote: ↑Mon Oct 22, 2018 3:45 pmI can only imagine "the sudden G-forces" causing an interrupt in voltage supply due to a short loss of contact - which in turn caused a reset. Beyond this, the effect of gravity on electrons should be negligible.Dave Britten wrote: ↑Mon Oct 22, 2018 2:04 pmHowever the sudden G-forces caused the device to reset...
Edited to correct an error in a foreign language.
Re: Machine reset after drop
RecommendedDave Britten wrote: ↑Mon Oct 22, 2018 5:12 pmThe battery probably bounced away from the contacts for just a moment. Which makes me wonder if I could solder a small 3V cap across the two battery lines to smooth out such brief losses of power. If I did, I would just take it on faith that it works, rather than repeatedly dropping the calculator on pavement to confirm.
WP43 SN00000, 34S, and 31S for obvious reasons; HP-35, 45, ..., 35S, 15CE, DM16L S/N# 00093, DM42β SN:00041
Re: Machine reset after drop
You could do that Dave. Or you could just, you know, not drop your calculatorDave Britten wrote: ↑Mon Oct 22, 2018 5:12 pmWhich makes me wonder if I could solder a small 3V cap across the two battery lines to smooth out such brief losses of power.
DM42 SN:00210
DM41X SN:00014
DM41X SN:00014
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Re: Machine reset after drop
That would be my Plan A. But I find it never hurts to have a good Plan B.Logan wrote: ↑Mon Oct 22, 2018 5:57 pmYou could do that Dave. Or you could just, you know, not drop your calculatorDave Britten wrote: ↑Mon Oct 22, 2018 5:12 pmWhich makes me wonder if I could solder a small 3V cap across the two battery lines to smooth out such brief losses of power.
Could also be useful for doing a battery change without clearing memory, if it's a big enough cap (no idea how to size for that since I'm not an EE).