I also don't think we need a battery to keep time for the pacsat file system. We only need accurate time for file uploads and to expire old files. Those processes can be automatically suspended if the time is not set. The time is then fixed by sending a command that sets the clock.
If we need accurate time for another reason, such as an experiment, then that could change of course.
For telemetry we can fall back on using reset and uptime.
73 Chris
On Tue, Apr 16, 2024, 20:36 Bob Stricklin via pacsat-dev < pacsat-dev@amsat.org> wrote:
I would say a battery is not needed.
The clock chip is the only device on the board that has a volatile memory and the current required to keep the data in place is very low. With the capacitors on the PCB the time should be maintained over a month. This is something we can test however it would be difficult to obtain an exact time to live because when you power up to read the clock the caps will be recharged.
Assuming it will be possible to set the time shortly before launch or even after launch it will be best not to have the added burden of a battery.
Bob
On Apr 16, 2024, at 2:18 PM, Bill Reed via pacsat-dev <
pacsat-dev@amsat.org> wrote:
Should the blinky RTC have a battery?
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Chris Thompson