Question: (see below if you want context)
If you have a profffie board on but have a preset active that draws minimal current (black LED colors, no sound) how long would the battery last?
I’ve been wondering there is a way to have a sabe’s switches function as a true on/off switch. Kill switches are quite handy but usually buried inside the chassis requiring unscrewing or revival of machine screws.
I have been using a preset that acts as a safety (like you would find on a real weapon). It has minimal functionality and basicallly is there to force you to arm the saber (by switching presets) before it will fire up. I was wondering if a preset that has as minimal functionality could function as an on/off switch. I imagine some current is drawn even in a preset that isn’t doing anything. But is it little enough that the battery would last a functionally indefinite amount?
Any risk of overheating or other problems with this idea?
It takes very little current to very quickly rapidly reduce the expected battery life.
The real problem isn’t the big things like the neopixels at that point, it’s all the little things drawing a few mA each that adds up.
The CPU itself doesn’t ever go into a “deep” sleep if I recall correctly, so it’s always drawing a few mA at least, anything hooked up to the saber, such as displays (OLED) will likely draw a couple mA, and a bunch of the onboard circuitry draws a few mA combined even when doing nothing.
At just 10mA draw, given a 3000mAh battery, you’re looking at 300 hours of runtime, and that’s shy of two weeks.
Of course, people get longer standby times, so it’s generally less than that, but it depends on the install.
To your question though, proffie already will turn things off with its “Idle Timeout,” when it’s off. A separate preset with all black won’t do anything unless the alternative is a bladestyle that is always on.
Thanks. Looks like dark mode won’t work as a means of having switches function as an on/off. Thanks for the clarification.
This is about run time in “standby”, which is a fairly complicated topic.
ProffieOS tries very hard to turn off anything it doesn’t need to save power.
When everything is turned off, it also reduces the clock speed, further reducing power.
If everything works, power is reduced down to the point where standby time is somewhere around 6 months…
However, there is a long list of things that will prevent this, like touch buttons, bluetooth, styles that keep running, etc. etc.
Having a preset with all black colors a weird case.
On one hand, “black” is special, and ProffieOS knows that it can turn off the power when a blade is black, so the blade itself shouldn’t actually draw any more power than in standby.
However, I think a few things do not turn off while the saber is “on”, like the motion chip. This will reduce standby time, but you would need to actually measure to figure out how much.
It’s possible to fix ProffieOS so that you could have a “standby” preset, but it would take some coding, and some measuring…
The CPU can go very low on power draw. I think down to 0.6mA with current setup.
This used to be the case, but starting in ProffieOS 7, I figured out how to turn the display off when not in use, and it draws very little when off. (So little it doesn’t matter.)
A bit of an over-estimation. The only things that always draw power is the 3.3v regulator and the voltage divider for battery tests. Together they draw somewhere around 0.05mA I think.
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