Energy-saving patch for Android version-Nook 4/4e

[Tialex]

Hi,

finally the super-flexible lua/KOReader ecosystem allowed me to reproduce the Nook Glowlight 4 deep sleeping between page turns with a single patch.

The patch page with a detailed Readme is at https://github.com/Codereamp/nopowen

Basically this patch sends the Nook into Deep Sleep after every page turn. So, a short period of wakefulness for preparing and showing a new page is followed by the longer one until you consume the page and decide to go to the next. This translates into about 3000+ page turns on a single charge, but the real number may be different depending on other operations and your habits.

My previous attempts was to find what's wrong with not sleeping, an attempt to make a cross-app solution (but it required an advanced preparation and root). The KOReader patch doesn't require root and needs only a couple
of simple actions and probably of reading a not-so-long readme

If you have any questions, and issues, please, post them here.

Thanks

[mergen3107]

Great idea! Might try some time later with my Onyx Boox.

My question is - does it send the device to deep sleep until next tap/swipe only? Can it wake on status bar clock updates? I had a lot of fun recently trying to kill Onyx’es native deep sleep to make progress bar clock work every minute https://github.com/koreader/koreader/issues/11037

[mergen3107]

So, like in usual page turns:
1) Turn page
2) Go to deep sleep
3) *wait for tap* - resume from deep sleep, do the page turn, go back to deep sleep.
4) *wait for minute change* - resume, update clock, go back to deep sleep.

Maybe at the (2) it should take current second, and set a timer to wake up? I don’t know if timers work during deep sleep though.

Also, does it go to deep sleep only after page turns, or after any action?

[NiLuJe]

You might want to look into the `Device:standby`(& the matching `canStandby` cap) implementation (e.g., on Kobo) and the autosuspend (not autostandby, that's one for PB) plugin's standby timer, and implement this as a standby method, you should get much saner scheduling behavior for free than simply hooking page turns this way .

[Tialex]

Originally Posted by mergen3107

So, like in usual page turns:
1) Turn page
2) Go to deep sleep
3) *wait for tap* - resume from deep sleep, do the page turn, go back to deep sleep.
4) *wait for minute change* - resume, update clock, go back to deep sleep.

Maybe at the (2) it should take current second, and set a timer to wake up? I don’t know if timers work during deep sleep though.

Also, does it go to deep sleep only after page turns, or after any action?

As for your first post and Onyx, I just looked at the Boox dates and all other infos, I highly doubt it is compatible but who knows. For everyone interested, there should be power_enhance_enable entry in the /data/system/users/0/settings_system.xml file. If it is then the script might be compatible. My current high probability guess is MobiScribe hardware since they explicitly mention this entry in their SDK.

I also see that you're very serious about your clock and how punctual it is From what I saw, theoretically it's possible to wake sooner that tap or press events come. But this would require more time to investigate and meanwhile not very high on my priority list, also because my usual per page reading time is less than a minute so I'm ok with the clock being a little off-time