Cannot write to /sys/class/rtc/rtc0/wakealarm

Hello,

I am trying to get wakeup of my HTPC set up. Following the exessive guidline from the MythTV wiki, I am already stuck at the first stages.
It seems that I cannot write to the SysFS file properly, but it does also not yield an error.

Whatever I want to echo into the wakealarm file, I only see that it updates the alarm_time with a short offset from now:

Libreelec# echo 0 > /sys/class/rtc/rtc0/wakealarm
Libreelec# cat /proc/driver/rtc
rtc_time        : 09:18:50
rtc_date        : 2017-04-01
alrm_time       : 09:23:43
alrm_date       : 2017-04-01
alarm_IRQ       : no
alrm_pending    : no
update IRQ enabled      : no
periodic IRQ enabled    : no
periodic IRQ frequency  : 1024
max user IRQ frequency  : 64
24hr            : yes
periodic_IRQ    : no
update_IRQ      : no
HPET_emulated   : yes
BCD             : yes
DST_enable      : no
periodic_freq   : 1024
batt_status     : okay
Libreelec#

The alarm_IRQ is not set, which means the box won't wake up.
Regardless of which epoch time I echo into the wakealarm file, it is always the same result. I only have a few minutes offset from the rtc_time and no IRQ.

What would be my next step to investigate?

Thank you.

Regards,
Marcus

Hello Nicolas,
I was just about to answer in your thread, but did not want to scatter the problem.
It is strange. It is not fixed for me in 8.0.1. Have a look:

login as: root
root@libreelec's password:
##############################################
#                 LibreELEC                  #
#            http://libreelec.tv             #
##############################################


LibreELEC (official) Version: 8.0.1
LibreELEC:~ # setwakeup.sh date '+%s' -d '+ 10 minutes'
sh: write error: Invalid argument
LibreELEC:~ #

However, the issue is less with the setwakeup.sh script, but more with the "date ..." construct which calculates the time into unix epoch.
This is broken on my machine.

I am right now doing this test: date +%s
This returns the seconds. Then I manually add 300 to this number and echo this into the wakealarm file.
This is indeed setting the time properly, and the box wakes up.
I am also toggele the alarm interupt on/off when I alternately echo the seconds and 0 into the wakealarm.

Only don't ask me why it did not work previously when I opened the thread. I assume I have had a typo in my manual calculation and missed a digit.
Every timepoint in the past is not set, which makes sense. Still need to verify this further.

Regards,
Marcus

Well, it is not really great as long as the "date ..." construct is not working.
Or do I not need this?

How do I tell TVHeadend to call the setwakeup.sh script?

Nicolas,

are there any changes to a script required as described in the readme.pdf document?
I installed the addon and did a reboot, but I cannot see that a timer is written to the /proc/driver/rtc.

Thank you for your great support!

Marcus

Hi Nicolas,

the error was sitting in front of the computer.
Right now, I am still working a lot with the TVH web interface for the basic setup. Not so much from the Kodi GUI.
I assumed that the Kodi addon would also recognize that I plan recordings directly from the web interface. This was not the case.

I will probably switch to another shutdown script and embed this as system.d service because I do not want to be limited to Kodi only.
I like to browse the EPG data from my Android app and define a recording from there. For these ones, the wakeup needs to be set as well.

A sample recording from Kodi is indeed waking up the computer on time!
Thanks for the help.

Regards,
Marcus