K4 BEGINNER: Script to sleep/wake up periodically

[mfuhlendorf]

Hello!

I'm a longtime reader of this forum, and have used many of the hacks here in my kindles for over a decade (I love the custom screensavers!), but this is my first post.

I come here kindly asking for help, as a newbie coding for the kindle. I work with programming and scripting, but mostly for the web (PHP, JS, etc) and PowerShell windows scripting. I have dabbled in Unix shell scripting, but I'm not confident enough to start meddling with the kindle right away.

Here is what I want to do. I recently found my old K4 lying around, after a move, in an old box. I jailbroke it and installed KUAL and linkss. I want to write a script to force the kindle to go to sleep for a set amount of time, and then wake up for a second and go back to sleep. In conjunction with the linkss tool, it will effectively become a dumb BW, veeery low power digital picture frame, with a few hundred pictures loaded directly via USB after formatting in Lightroom (I first thought of using the Online screensaver tool, but then it would use a lot more battery power).

I found many useful guides here, but no comprehensive detail of the kindle lab126 functions that deal with sleep and wake up, setting up timers, etc.

Can anyone experienced point me in the right direction?

Thanks in advance

[NiLuJe]

You'll have to deal with RTC shenanigans, and that's always... fun.

I *think* it's been done on a K4, though, but I'll be damned if I can remember when/where :/.

[yparitcher]

It was me of course.

https://www.mobileread.com/forums/sh...d.php?t=315119

https://www.mobileread.com/forums/sh...d.php?t=322900

[mattcd216]

Originally Posted by yparitcher

It was me of course.

https://www.mobileread.com/forums/sh...d.php?t=315119

https://www.mobileread.com/forums/sh...d.php?t=322900

newbie here, be gentle

Your scripts - are they run by cron or something? and do they both wake then lock the screen?

I'm looking to automatically unlock the kindle, wait a few seconds and then re-lock in order to change the screensaver (photoframe project).

Thanks,
matt

[yparitcher]

You run them on the command line (via ssh) and it waits litening for the system state to change.

It will put the kindle back to sleep

[mattcd216]

Originally Posted by yparitcher

You run them on the command line (via ssh) and it waits litening for the system state to change.

It will put the kindle back to sleep

Thanks. And I presume they’ll run indefinitely, until a reboot or shutdown?

[mattcd216]

Struggling a bit.

I saw in one of the threads linked that

lipc-send-event com.lab126.powerd.debug dbg_power_button_pressed

simulates the lock button being pressed.

So a simple script:

#!/bin/sh
lipc-send-event com.lab126.powerd.debug dbg_power_button_pressed
sleep 5
lipc-send-event com.lab126.powerd.debug dbg_power_button_pressed

would achieve what I'm after, if I could schedule it to run periodically.

Does a jailbroken kindle have a cron scheduler, or similar?

Appreciate the help.
Matt

[mattcd216]

Found root's crontab. That'll do

Scheduled every 5 mins and that looked to work ok. Set to @daily now, so will see if the image refreshes overnight.

Matt

[mattcd216]

I take it back. 5 minute cron job is... intermittent. Sometimes works, sometimes doesn't. Haven't spotted a pattern in the behaviour yet.

Will keep trying/experimenting.

[yparitcher]

Originally Posted by mattcd216

Thanks. And I presume they’ll run indefinitely, until a reboot or shutdown?

Correct.

A cron job is not enough, as cron only runs while the kindle is awake.
You need to set a rtc wakealarm to ensure that the kindle wakes up from sleep.

Lipc-wait-event also has a flag to tell it how many times to run, if you dont want it to run forever.

[mattcd216]

Thanks for the help @yparitcher.

Couple of questions on your two scripts in this thread:
1. Do both of the scrips need to be run, or does one trigger the other?
2. Could/should they then be added to cron to run on boot?
3. I notice in program script the space to set picture with eips/fbink - I am hoping to use the screensaver hack to display a random image when the kindle is asleep, is this compatible?
4. I put in the eips command, ran, and got:

line 3: syntax error: "do" unexpected

Matt

[mattcd216]

@yparitcher trying your other single script you linked instead.

I gather this monitors states and when the kindle goes in to readyToSuspend it sets the rtcWakeup. I changed only the delta to 20 to test. Ran the script.

I locked the kindle both with the power button and also by waiting the 10 minutes for it to lock itself. Couldn't get any automatic wake from the script.

Where does the logger log to? Would be handy to troubleshoot what's happening.

Thanks again

[NiLuJe]

Originally Posted by mattcd216

Where does the logger log to? Would be handy to troubleshoot what's happening.

`showlog` (append `-f` if you want a live feed, àlà `tail`).

[tubular]

Originally Posted by mfuhlendorf

Hello!

I'm a longtime reader of this forum, and have used many of the hacks here in my kindles for over a decade (I love the custom screensavers!), but this is my first post.

I come here kindly asking for help, as a newbie coding for the kindle. I work with programming and scripting, but mostly for the web (PHP, JS, etc) and PowerShell windows scripting. I have dabbled in Unix shell scripting, but I'm not confident enough to start meddling with the kindle right away.

Here is what I want to do. I recently found my old K4 lying around, after a move, in an old box. I jailbroke it and installed KUAL and linkss. I want to write a script to force the kindle to go to sleep for a set amount of time, and then wake up for a second and go back to sleep. In conjunction with the linkss tool, it will effectively become a dumb BW, veeery low power digital picture frame, with a few hundred pictures loaded directly via USB after formatting in Lightroom (I first thought of using the Online screensaver tool, but then it would use a lot more battery power).

I found many useful guides here, but no comprehensive detail of the kindle lab126 functions that deal with sleep and wake up, setting up timers, etc.

Can anyone experienced point me in the right direction?

Thanks in advance

My reply is a bit late, but I think it's still useful to share.
This project is basically what you want: https://github.com/pascalw/kindle-dash
It's very power efficient, think only needing to charge your Kindle once a month.