demi733
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Re: Under-voltage warnings [solved]

Sat Sep 24, 2016 8:10 am

Ok. echo powersave | sudo tee /sys/devices/system/cpu/cpu[0-3]/cpufreq/scaling_governor works well enough. However, I have reached another quark. I would like to change the default governor to powersave. I edited /etc/xdg/lxsession/LXDE-pi/autostart to include the following @/bin/echo powersave | /usr/bin/sudo /usr/bin/tee /sys/devices/system/cpu/cpu[0-3]/cpufreq/scaling_governor but a cat /sys/devices/cpu/cpu0/cpufreq/scaling_governor returns "ondemand". I would prefer to use /etc/rc.local or /etc/init.d/rc.local to achieve the results during boot as opposed to when the desktop loads. Every forum I've read states that rc.local is very particular and simple mistakes can cause volatile boots and render the system unusual. I wish to avoid disaster recovery and am refraining until I can get expert advice on the subject. Any help will be greatly appreciate. Particularly, if you know for certain that your solution works. I.E., it works on your pi. Please and thank you.

dom
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Re: Under-voltage warnings

Sat Sep 24, 2016 12:08 pm

demi733 wrote:Ok. echo powersave | sudo tee /sys/devices/system/cpu/cpu[0-3]/cpufreq/scaling_governor works well enough. However, I have reached another quark. I would like to change the default governor to powersave. I edited /etc/xdg/lxsession/LXDE-pi/autostart to include the following @/bin/echo powersave | /usr/bin/sudo /usr/bin/tee /sys/devices/system/cpu/cpu[0-3]/cpufreq/scaling_governor but a cat /sys/devices/cpu/cpu0/cpufreq/scaling_governor returns "ondemand". I would prefer to use /etc/rc.local or /etc/init.d/rc.local to achieve the results during boot as opposed to when the desktop loads. Every forum I've read states that rc.local is very particular and simple mistakes can cause volatile boots and render the system unusual. I wish to avoid disaster recovery and am refraining until I can get expert advice on the subject. Any help will be greatly appreciate. Particularly, if you know for certain that your solution works. I.E., it works on your pi. Please and thank you.
Try editing /etc/init.d/raspi-config which is where ondemand is initially set.

demi733
Posts: 5
Joined: Thu Sep 22, 2016 6:26 am

Re: Under-voltage warnings

Sat Sep 24, 2016 2:13 pm

Thank you, sir. I've modified /etc/init.d/raspi-config as follows, in case anyone else happens to be attempting to do the same;
# Short-Description: Switch to powersave cpu governor (unless shift key is pressed)
printf " Yes. Not enabling powersave scaling governor"
log_end_msg 0
else
printf " No. Switching to powersave scaling governor"
SYS_CPUFREQ_GOVERNOR=/sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
if [ -e $SYS_CPUFREQ_GOVERNOR ]; then
echo "powersave" > $SYS_CPUFREQ_GOVERNOR
echo 50 > /sys/devices/system/cpu/cpufreq/powersave/up_threshold
echo 100000 > /sys/devices/system/cpu/cpufreq/powersave/sampling_rate
echo 50 > /sys/devices/system/cpu/cpufreq/powersave/sampling_down_factor

I've swapped all instances of "ondemand" with "powersave" for comments, logging and path. A quick cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
powersave
This shows that powersave is acting as the governor and a more thorough output further proves this is functioniing properly.
GPU Temperature = temp=49.4'C
CPU Temperature = 49'C
Raw Temperature = 49388
Core Voltage = $volt=1.2000V
SDRAM Core Voltage = $volt=1.2000V
SDRAM I/O Voltage = $volt=1.2000V
SDRAM Phy Voltage = $volt=1.2250V
MAX Freguency = 1200000
MIN Frequency = 600000
CPU0 Frequency = 600000
CPU1 Frequency = 600000
CPU2 Frequency = 600000
CPU3 Frequency = 600000
ARM Frequency = $frequency(45)=600000000
Core Frequency = $frequency(1)=250000000
h264 Frequency = $frequency(28)=250000000
isp Frequency = $frequency(42)=250000000
v3d Frequency = $frequency(43)=250000000
uart Frequency = $frequency(22)=48000000
pwm Frequency = $frequency(25)=100000000
emmc Frequency = $frequency(47)=250000000
pixel Frequency = $frequency(29)=40000000
vec Frequency = $frequency(10)=0
hdmi Frequency = $frequency(9)=163682000
dpi Frequency = $frequency(4)=0
Thanks again for your input!

buti
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Joined: Thu Oct 13, 2016 2:32 pm

Re: Under-voltage warnings

Fri Oct 14, 2016 7:29 am

hi dom,

i really like the new icons! would it be feasible to make the distance from top and right edge configurable in config.txt? that would be really useful for my application.

i also vote for klog messages in addition – something like the machine check exception messages on x86.

dom
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Re: Under-voltage warnings

Fri Oct 14, 2016 1:17 pm

buti wrote: i really like the new icons! would it be feasible to make the distance from top and right edge configurable in config.txt? that would be really useful for my application.
Explaining what the application is that would benefit from moving the icons would be useful.

buti
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Re: Under-voltage warnings

Fri Oct 21, 2016 1:37 pm

dom wrote:Explaining what the application is that would benefit from moving the icons would be useful.
i'm working on an attitude indicator for an ultralight airplane. i already have warning / error indicators in the upper-right corner. the pi icons are too far from the corner, so they appear exactly above the compass ring and are hard to see.

i'd like to place the under-voltage or overheating warning icons just below the other (currenty very dark) error indicators in the top right corner. please note, that the resolution will probably change.
fbgrab090.png
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mikerr
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Re: Under-voltage warnings

Fri Oct 21, 2016 9:09 pm

Get rid of the sysyem indicators completely;

Config.txt:

Code: Select all

avoid_warnings=1
And then display your own custom status yourself by checking gpio35 (red LED)
- see my python code earlier in this thread:
viewtopic.php?f=29&t=82373&start=75#p739517

Or poll:

Code: Select all

vcgencmd get_throttled
If not 0, it's throttled by voltage or temp

Or use my code
Android app - Raspi Card Imager - download and image SD cards - No PC required !

buti
Posts: 3
Joined: Thu Oct 13, 2016 2:32 pm

Re: Under-voltage warnings

Mon Oct 24, 2016 2:15 pm

hi mike,
thanks for the suggestion. i will try something similar, probably using gpiozero + polling /sys/class/thermal/thermal_zone0/temp.
mikerr wrote:Get rid of the system indicators completely;

Config.txt:

Code: Select all

avoid_warnings=1
And then display your own custom status yourself by checking gpio35 (red LED)
- see my python code earlier in this thread:
viewtopic.php?f=29&t=82373&start=75#p739517
...

simonspark
Posts: 12
Joined: Wed Nov 30, 2016 9:23 pm

Re: Under-voltage warnings

Wed Nov 30, 2016 9:40 pm

Any reason why I would be seeing this under-voltage warning every couple seconds out of the blue on my Pi3?

I hooked up a USB volt reader, it is consistently over 5V. When the warning appears on the screen, the reader is still above 5. I tried several different cables, including known high-quality ones (such as Blackberry).

I can get this warning while just hanging out on the desktop screen, with 0% CPU being used and idling.

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mahjongg
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Re: Under-voltage warnings

Wed Nov 30, 2016 11:54 pm

simonspark wrote:Any reason why I would be seeing this under-voltage warning every couple seconds out of the blue on my Pi3?

I hooked up a USB volt reader, it is consistently over 5V. When the warning appears on the screen, the reader is still above 5. I tried several different cables, including known high-quality ones (such as Blackberry).

I can get this warning while just hanging out on the desktop screen, with 0% CPU being used and idling.
you will need an oscilloscope to catch the very short dips that can trigger the under voltage protector, also you must measure behind the polyfuse, as its possible the drops are caused by a polyfuse that has developed some resistance. So measure from one of the 5V GPIO pins, not from the USB cable, or even the supply.

simonspark
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Re: Under-voltage warnings

Wed Nov 30, 2016 11:56 pm

mahjongg wrote:
simonspark wrote:Any reason why I would be seeing this under-voltage warning every couple seconds out of the blue on my Pi3?

I hooked up a USB volt reader, it is consistently over 5V. When the warning appears on the screen, the reader is still above 5. I tried several different cables, including known high-quality ones (such as Blackberry).

I can get this warning while just hanging out on the desktop screen, with 0% CPU being used and idling.
you will need an oscilloscope to catch the very short dips that can trigger the under voltage protector, also you must measure behind the polyfuse, as its possible the drops are caused by a polyfuse that has developed some resistance. So measure from one of the 5V GPIO pins, not from the USB cable, or even the supply.

Thank you for your reply. I will need to do some research, as I am not too sure at the moment what you mean.

I am not sure if it matters, but this only started recently. When I first got the Pi3, I did not have this issue. I also have a Pi 2 B+, which does not have this issue.

Thanks

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RaTTuS
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Re: Under-voltage warnings

Thu Dec 01, 2016 7:44 am

your PSU is probably failing
How To ask Questions :- http://www.catb.org/esr/faqs/smart-questions.html
WARNING - some parts of this post may be erroneous YMMV

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simonspark
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Re: Under-voltage warnings

Thu Dec 01, 2016 12:37 pm

RaTTuS wrote:your PSU is probably failing
How to validate that? Would mahjongg suggestion verify that?

The Pi is only 2-3 weeks old.I tried several wall outlet adapters (if that is what was meant by PSU).

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B.Goode
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Re: Under-voltage warnings

Thu Dec 01, 2016 12:43 pm

Have you checked that your wall adapters meet the power requirements of the RPi 3?

https://www.raspberrypi.org/help/faqs/#powerReqs

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RaTTuS
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Re: Under-voltage warnings

Thu Dec 01, 2016 12:52 pm

simonspark wrote:
RaTTuS wrote:your PSU is probably failing
How to validate that? Would mahjongg suggestion verify that?

The Pi is only 2-3 weeks old.I tried several wall outlet adapters (if that is what was meant by PSU).
well you said
am not sure if it matters, but this only started recently. When I first got the Pi3, I did not have this issue. I also have a Pi 2 B+, which does not have this issue.
so I assumed it was working fine and has become dodgy over time..
a Pi2 uses a lot less power than a Pi3.
if your PSU is 2.4A or better then it will [should] be fine if it is less then you may have problems
How To ask Questions :- http://www.catb.org/esr/faqs/smart-questions.html
WARNING - some parts of this post may be erroneous YMMV

1QC43qbL5FySu2Pi51vGqKqxy3UiJgukSX
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simonspark
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Re: Under-voltage warnings

Thu Dec 01, 2016 5:55 pm

RaTTuS wrote:
simonspark wrote:
RaTTuS wrote:your PSU is probably failing
How to validate that? Would mahjongg suggestion verify that?

The Pi is only 2-3 weeks old.I tried several wall outlet adapters (if that is what was meant by PSU).
well you said
am not sure if it matters, but this only started recently. When I first got the Pi3, I did not have this issue. I also have a Pi 2 B+, which does not have this issue.
so I assumed it was working fine and has become dodgy over time..
a Pi2 uses a lot less power than a Pi3.
if your PSU is 2.4A or better then it will [should] be fine if it is less then you may have problems

Ahh, that is it I bet. Stupid me... I thought it was enough power because my Pi 2 works. Checking the link provided below though, this explains everything. a 2A would work for one, and not the other.
B.Goode wrote:Have you checked that your wall adapters meet the power requirements of the RPi 3?

https://www.raspberrypi.org/help/faqs/#powerReqs

Thanks guys! I am on the hunt for a better power supply.

rasp_me
Posts: 6
Joined: Tue Dec 27, 2016 10:28 pm

Re: Under-voltage warnings

Wed Dec 28, 2016 2:22 pm

Hi,

I just setup my first Pi3 B+ with OpenElec. It works fine but I also get a colored square. I have the Rasperry Pi starter kit PSU with 2.5 A (cannot change the USB cable as it is fix).
I measured 5,16 V between PP3 and PP7 (like described here: viewtopic.php?f=28&t=84874).
So if I understand it right, this should be fine.

Any ideas what could be wrong and I could do (except turning off the warning?)

regards
ME
Last edited by rasp_me on Wed Dec 28, 2016 3:49 pm, edited 1 time in total.

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FTrevorGowen
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Re: Under-voltage warnings

Wed Dec 28, 2016 2:31 pm

rasp_me wrote:Hi,
I just setup my first Pi3 B+ with OpenElec. It works fine but I also get a colored square.
...
ME
What version of OpenElec (the icons were changed some time ago for Raspbian, whether OpenElec now uses those I don't know but you could be using a "too old " version and/or confusing the low-voltage warning with the over-temperature one maybe?)?
Trev.
Still running Raspbian Jessie on some older Pi's (an A, B1, B2, B+, P2B, 3xP0, P0W) but Stretch on my 2xP3A+, P3B+, P3B, B+, A+ and a B2. See: https://www.cpmspectrepi.uk/raspberry_pi/raspiidx.htm

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rpdom
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Re: Under-voltage warnings

Wed Dec 28, 2016 2:34 pm

That OpenElec must be using some old boot files/firmware, as the coloured squares have now been replaced by a lightning bolt for low power and a thermometer for overheating.

What colour square are you getting? The old firmware had multi-coloured for low power and plain red/orange for overheat.

rasp_me
Posts: 6
Joined: Tue Dec 27, 2016 10:28 pm

Re: Under-voltage warnings

Wed Dec 28, 2016 2:43 pm

I use the latest stable version: http://openelec.tv/get-openelec/categor ... pi2-builds
=> OpenELEC-RPi2.arm-6.0.3.img.gz

The square is multi-coloured (red, yellow, dark blue, bright blue).

When you are saying a too old version .. was there a bug in the older version?

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rpdom
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Re: Under-voltage warnings

Wed Dec 28, 2016 3:18 pm

rasp_me wrote:The square is multi-coloured (red, yellow, dark blue, bright blue).
Ok, yes, that is the low voltage warning. Does the red PoWeR LED will turn off at the same time as that square appears?
When you are saying a too old version .. was there a bug in the older version?
No bugs, just a change in the symbols displayed on the screen to make it clearer what they are reporting.

rasp_me
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Re: Under-voltage warnings

Wed Dec 28, 2016 3:31 pm

I updated to the latest developer release now: OpenELEC-RPi2.arm-6.95.3.img.gz

There is an improvment with the new version. I still get the big multi-coloured square during boot time and the small multi-coloured square appears at the beginning when kodi is loaded but it fades out after a few seconds. It sometime fades in again (e.g. when I press pause button during the movie and then play again) and then it fades out after another few seconds.

The multimeter always shows exactly the same 5.16V on PP3 and PP7 - no matter if the square is there or not.
The red power LED is always on - no matter if the square is there or not.

(Btw. I tested it with another PSU, also 2.5 A and have the same results. I also tested another HDMI cable on another HDMI port on the TV. The movie is streamed via SMB on physical eth - so now HDD drive or wifi.)

Edit: (I edited 5.22V to 5.16V ... 5.22V was between PP1 and PP3)

luwi
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Re: Under-voltage warnings

Mon Mar 20, 2017 12:45 pm

Yes, power supply is very important. The current 2,5A is not only one parameter you need to guarantee. You need also this two parameters:
- linear adjustment +/-2%,
- load regulation +/- 5%,
Unfortunately I had to research this detailed information because it wasn't attached to my raspberry pi 3.

ldon13
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Location: Australia

Re: Under-voltage warnings

Wed Apr 05, 2017 2:08 am

Hey guys,

I would like to clarify if this is correct, Im getting low voltage when connected to hdmi, as long as the power led is red solid, it would be fine and ignore the lightning bolt. If the red power led is blinking on and off, i should take action and replace the power supply.

Thankyou.

jamesh
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Re: Under-voltage warnings

Wed Apr 05, 2017 9:17 am

314_PIE wrote:Hey guys,

I would like to clarify if this is correct, Im getting low voltage when connected to hdmi, as long as the power led is red solid, it would be fine and ignore the lightning bolt. If the red power led is blinking on and off, i should take action and replace the power supply.

Thankyou.
if you get the lightening bolt, then you should really be looking to improve the power supply/usb cable. It's there for a reason!
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