I've been using Cesium for awhile now and I like it. However, I've noticed a few things with my battery when using Cesium and I am not sure if there is a connection or not, hoping the community can help me out.

1. I like to use TiBoy and I had Pokemon Gold installed which took up a lot of memory. At one point I had about 15% of memory left. Question - does filling the memory too much cause more battery drain? I seem to recall reading that more memory required more power to store but I am not sure how reliable or accurate this was. If this is is the case, what is an ideal upper storage limit on what's available. (And a little aside, why have so much memory tucked away from the user if not to just provide this buffer and leave full user memory to the user without draining the battery?).

2. I really like the on shortcuts in Cesium however I am curious how these work and whether the program running in the background drains battery. Again, only because I've noticed significantly more battery drain between uses with Cesium install then without. I've turned off on shortcuts for the past month and noticed a better charge over time, but again this is just a casual observation. Also curious about the power-off feature with password. Does this power down the device the exact same as normal off or does something stay running in the background?

Sorry to throw all of this. I am just trying to figure this out and would love to be told I'm out to lunch and given reasons why. 😄

The main consumer of power on the CE is the screen. The main factor in power drain is just how long the screen is turned on and what brightness it's at.


A larger memory chip would require more power than a smaller one, but the CE has a fixed amount of memory, so the RAM and flash themselves should use approximately the same amount of power regardless of what's stored in them.

Many operations in the CE's OS have worst-case runtime that's linear with the number of variables on the calculator or the total size of the variables in RAM, which slows the OS down slightly the more variables you have. In turn the processor is idle for less time, which can increase power consumption. But again, this should be negligible compared to the power consumption of the screen backlight.

(it's worth noting that most CE games never idle the processor, so games will use a bit more power than the OS does, but there shouldn't really be a difference in power usage between games).


These are implemented using hooks. Cesium doesn't actually "run in the background," the OS just calls some of its code whenever you e.g. press a key. The rest of the time Cesium isn't doing anything at all.

Backing up RAM might actually use a decent amount of battery because it involves writing to flash memory, which is a power-hungry operation.

Overall it basically comes down to how often you're using it and what the screen brightness is set to. Unfortunately it's pretty hard to experiment with because the calculator only reports four distinct battery levels.

Thank you very much for that detailed explaination commandz. I suppose I should just be clear and say that what I am experiencing is a drain in the battery between calculator uses. And I've really only noticed this drain recently after the artiface hack and install Cesium and using TiBoy. That is what lead me down the hole of perhaps background running or something with memory now that I am filling up the archive more than any time in the past with the calculator no hacked.

That all being said, it is entirely possible that I just have one of those bum batteries and I am just now starting to see the effect. Is there anything that could be draining the battery between calculator uses while it is just powered off and on my desk?

The CE has a "deep sleep" mode which activates after being off for a long time. If you are using the calculator more frequently, it will spend less time in deep sleep when off, which might account for some of that difference. Also, the calc will never go into deep sleep if it's in exam mode, so you should not leave it in exam mode indefinitely. (I know you're probably not doing that)
It might also be that your batteries are just getting older.