Does this only work on x86_64?
Works fine on X86_32 for me --Benjsc 12:56, 3 October 2006 (UTC)
It works on 32 bit as well. If you miss /proc/acpi/alarm then it seems that this dissapears if you run smp.
Does anyone have experience with the Via EPIA boards? I'm not able to get it working and thus still use nvram-wakeup...
How do I use ACPI wakeups with MythWelcome? The instructions for it are all for using it with nvram-wakeup. --Turpie 11:09, 29 December 2006 (UTC)
http://svn.mythtv.org/trac/ticket/2838 Looks like capability for ACPI with MythWelcome is coming. Hopefully we'll see an update to the WIKI once 0.21 comes out or sooner if someone with svn version gets ambitious.
I just updated my fedora 7 kernel and apparently the 2.6.22 linux kernel removes the /proc/acpi/alarm feature, see http://lkml.org/lkml/2007/6/22/320 does anyone know the new method for these new kernels? --Vossman 06:18, 23 July 2007 (UTC)
There is no documentation, only some hidden description in the git commit that introduced this feature. So I wrote some short documentation, but it isn't included in the source tree yet, AFAIK.
It can be found here:
There is also a message in the mythtv mailing list here:
I found a note here that says: "Also it seems, that /sys/class/rtc/rtc0/wakealarm only accepts times more than 2h in the future." If you are having problems this might be it.
--Vossman 07:25, 7 September 2007 (UTC)
I am having the same issue as this guy here  I have no trouble getting the value into the /sys/class/rtc/rtc0/wakealarm that is all fine and dandy. But my machine does not wake up when I set this value. I use Fedora 7 and /proc/acpi/alarm worked great before. I am thinking of reporting this to bugzilla.kernel.org and bugzilla.redhat.com if other people are experiencing this post a comment. --Vossman 16:01, 8 September 2007 (UTC)
Fedora Core 6 kernel 188.8.131.52 vs kernel 184.108.40.206
I have a backend running FC6 (kernel 220.127.116.11-49.fc6) that shuts down and wakes up just fine using the script mentioned in the article. However, after upgrading to kernel 18.104.22.168-61.fc6, it no longer works. I figured out (thanks to the comment in the article) that a new wakeup mechanism is in place for the new kernel, namely /sys/class/misc/rtc/power/wakeup. I tried using that, but all I get when I try to echo anything into it (as root) is "invalid argument". Even resetting fails (echo 0 > /sys/class/misc/rtc/power/wakeup). As of writing, this article is the *only* place that mentions this path in google's index. I've reverted to the 22.214.171.124 kernel which still works great, using mythtv-0.20.2-167.fc6. Judaz 19:16, 6 November 2007 (UTC)
strage stript for the wakealarm feature in new kernels
The script is somewhat strange in some parts.
#!/bin/sh # $1 is the --settime switch that nvram-wakeup normally expects # $2 is the date/time in seconds since 1970 DATE=`date -d "1970-01-01 $2 sec" "+%F %H:%M:%S" -u` SECS=`date -d "1970-01-01 $2 sec" "+%s" -u`
Why is the argument $2, which is seconds since epoch, converted into seconds since epoch? I think that part can be scratched. Just echo $2 > /sys/class/rtc/rtc0/wakealarm should do fine (at least it does for me)
# Save the wakeup time echo "$*" > /myth.wakeup.args echo $DATE > /myth.wakeup.time echo $SECS > /myth.wakeup.secs
Why are files written into the root directory? Just scratching the "> /myth.wakeup.args" should be fine, as the echo output can be seen in the backend log then.