[aprssig] APRS Runner Tracking
kf4lvz at yahoo.com
Wed Aug 7 17:35:47 EDT 2013
>>> Set your position to your checkpoint. Then each time you want to
>>> report a particular runner number, just change the MYCALL of the radio
>>> to the runner number...
>> Interesting idea but you won't catch me doing it and
>> that's because you're forgetting that the radio stores data
>> in flash memory which has a finite lifetime. I prefer
>> not to wear out the flash memory in my radio prematurely
> Hummh. I have about 8 or so D7's between my oriingal prototype and all
> the ones at work, and so the age is from 15 years old to about 10 years
> old, and not one of them has failed for anything, though several have no
> control knob from having bounced on concrete numerous times.
>> It all gets stored in flash which wears out.
> Yes, but 100,000 cycles is sure a long long time. Let say 20 entries per
> marathon 5 marathons a year, that is about 1000 years life. I doubt even
> Kenwood will be around then...
The cycles are usually referenced to a chip and that assumes mitigation
methods like wear-leveling. A typical flash memory cell (not the whole
chip, just one memory bit location) can't handle that many writes (it's
usually 10,000 or less). Kenwood likely didn't use a smart chip in the
memory module but instead used a simple flash device to act like an
EEPROM (direct addressing). That means a specific set of cells gets
rewritten every time a particular parameter changes instead of the
writes being distributed across all the cells as would be the case in a
Now the calculation says 100 years instead of 1000, which is still quite
a while, but that also assumes the chip is in excellent health (and we
know what happens when assumptions are made).
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