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#1 Ali DSD

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Posted 29 December 2012 - 09:19 AM

I know many users are facing this problem but it's very troublesome as you can not rely on battery percentage.
I am using 1031.tm
I have used a lot of battery calibration tools but no success.
Does anyone know the cause and possible fix for this problem?

Thanks

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#2 Tzul

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Posted 29 December 2012 - 02:00 PM

I have used a lot of battery calibration tools but no success.

More people need to realize that you cannot "calibrate" a battery and that apps promising that are lying.
Many are simply deleting batterystats.bin, but that has no effect on the battery level.

Does anyone know the cause and possible fix for this problem?


The cause is most likely a bug in the kernel, the power driver to be more specific.
Older versions had the "battery level stuck at 100%" problem, so they tried to fix that but in turn must have introduced the "shutdown at 40%" bug.
Just to make it clear, the tablet doesn't actually shut down with the battery still at 40%. It shuts down when the battery is empty (voltage below a certain threshold, about 3200mV for the Fire, I think). However, the code in the power driver that calculates/estimates the battery level is flawed, resulting in the display of a wrong percentage.

This should be relatively easy to fix - if we had the up-to-date source code for the kernel.
In principle, you could simply replace the battery level estimation function with a read-out of the battery meter that's built into the AXP202 power management chip. No need to come up with your own clever way of calculating the level. This would probably result in a battery meter that's a bit "jumpier" than the one we have (that is, the percentage wouldn't move as linearly as the current implementation), but at least it'd go from 100% to 0% as it should.

We have to demand the new kernel sources from Ainol or Amlogic (or whoever is responsible for that). They should be re-released with every new firmware.

Edited by Tzul, 29 December 2012 - 02:04 PM.

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#3 Billcnz

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Posted 29 December 2012 - 02:21 PM

More people need to realize that you cannot "calibrate" a battery and that apps promising that are lying.
Many are simply deleting batterystats.bin, but that has no effect on the battery level.



The cause is most likely a bug in the kernel, the power driver to be more specific.
Older versions had the "battery level stuck at 100%" problem, so they tried to fix that but in turn must have introduced the "shutdown at 40%" bug.
Just to make it clear, the tablet doesn't actually shut down with the battery still at 40%. It shuts down when the battery is empty (voltage below a certain threshold, about 3200mV for the Fire, I think). However, the code in the power driver that calculates/estimates the battery level is flawed, resulting in the display of a wrong percentage.

This should be relatively easy to fix - if we had the up-to-date source code for the kernel.
In principle, you could simply replace the battery level estimation function with a read-out of the battery meter that's built into the AXP202 power management chip. No need to come up with your own clever way of calculating the level. This would probably result in a battery meter that's a bit "jumpier" than the one we have (that is, the percentage wouldn't move as linearly as the current implementation), but at least it'd go from 100% to 0% as it should.

We have to demand the new kernel sources from Ainol or Amlogic (or whoever is responsible for that). They should be re-released with every new firmware.

If problem is in the kernel, why is not every one using that kernel affected? I can comfortably go below 10% without my device shutting down. I'm running CM10.1 which uses feiyu 1031 kernel but others on same kernel experience problems. It still feels to me that something gets messed up in the battery stats for some people when flashing ROMs and there should be a way to get it back in sync.

Sent from my Novo7Flame using Tapatalk HD and CM10.1

#4 Tzul

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Posted 29 December 2012 - 03:05 PM

If problem is in the kernel, why is not every one using that kernel affected?

Maybe everybody IS affected but many just don't know it yet. ;)
It could depend on how exactly you're using the tablet (how far down do you let the battery go before you recharge, how often do you recharge, the wear level of the battery, etc.).

When the 100% bug appeared, I first thought I wasn't affected either. Which turned out to be wrong. Yet I seemed to get it less frequently than Innerleaf, for example.

It still feels to me that something gets messed up in the battery stats for some people when flashing ROMs and there should be a way to get it back in sync.

If you mean /data/system/batterystats.bin, then that's been debunked, see my previous post.
The battery percentage reported to Android comes directly from the power driver part of the kernel. It doesn't use any of those higher-level Android features and files, but solely operates on the AXP202 power management chip. So if there were any "battery stats", you'd have to look there. Which brings us back to needing the updated source code.

Another issue with this new battery meter code is that it sometimes "recharges" when the tablet is off, meaning the battery percentage will magically increase, even though no charger is connected. You could say the power driver is "auto calibrating" or "getting back in sync", but I consider it another bug as it looks quite weird and can confuse people.

Edited by Tzul, 29 December 2012 - 03:06 PM.


#5 Ali DSD

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Posted 29 December 2012 - 03:56 PM

More people need to realize that you cannot "calibrate" a battery and that apps promising that are lying.
Many are simply deleting batterystats.bin, but that has no effect on the battery level.



The cause is most likely a bug in the kernel, the power driver to be more specific.
Older versions had the "battery level stuck at 100%" problem, so they tried to fix that but in turn must have introduced the "shutdown at 40%" bug.
Just to make it clear, the tablet doesn't actually shut down with the battery still at 40%. It shuts down when the battery is empty (voltage below a certain threshold, about 3200mV for the Fire, I think). However, the code in the power driver that calculates/estimates the battery level is flawed, resulting in the display of a wrong percentage.

This should be relatively easy to fix - if we had the up-to-date source code for the kernel.
In principle, you could simply replace the battery level estimation function with a read-out of the battery meter that's built into the AXP202 power management chip. No need to come up with your own clever way of calculating the level. This would probably result in a battery meter that's a bit "jumpier" than the one we have (that is, the percentage wouldn't move as linearly as the current implementation), but at least it'd go from 100% to 0% as it should.

We have to demand the new kernel sources from Ainol or Amlogic (or whoever is responsible for that). They should be re-released with every new firmware.


thank you very much @Tzul for the detailed explanation. hopefully someday it will be solved.

#6 Ali DSD

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Posted 29 December 2012 - 04:00 PM

Another issue with this new battery meter code is that it sometimes "recharges" when the tablet is off, meaning the battery percentage will magically increase, even though no charger is connected. You could say the power driver is "auto calibrating" or "getting back in sync", but I consider it another bug as it looks quite weird and can confuse people.


@Tzul your findings are 100% right, I also observed this, it increases the battery % without charging,I verified it with Battery Monitor log.

#7 Billcnz

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Posted 29 December 2012 - 04:04 PM

Maybe everybody IS affected but many just don't know it yet. ;)
It could depend on how exactly you're using the tablet (how far down do you let the battery go before you recharge, how often do you recharge, the wear level of the battery, etc.).

When the 100% bug appeared, I first thought I wasn't affected either. Which turned out to be wrong. Yet I seemed to get it less frequently than Innerleaf, for example.


If you mean /data/system/batterystats.bin, then that's been debunked, see my previous post.
The battery percentage reported to Android comes directly from the power driver part of the kernel. It doesn't use any of those higher-level Android features and files, but solely operates on the AXP202 power management chip. So if there were any "battery stats", you'd have to look there. Which brings us back to needing the updated source code.

Another issue with this new battery meter code is that it sometimes "recharges" when the tablet is off, meaning the battery percentage will magically increase, even though no charger is connected. You could say the power driver is "auto calibrating" or "getting back in sync", but I consider it another bug as it looks quite weird and can confuse people.

OK thanks, I was more wondering why I don't see the problem on my device. I started with 0910 qm stock fw, then progressed through upgrades including the AML 0921 using the flash tool that did have some fixes for AXP202 and since then onto the feiyu ROMs and flambe and CM10, AOKP and CM10.1 and I haven't had any battery issues. I wonder if the AML 0921 had some persistent changes on nand that were carried over - just guessing though.

Sent from my Novo7Flame using Tapatalk HD and CM10.1

#8 Ali DSD

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Posted 29 December 2012 - 04:38 PM

OK thanks, I was more wondering why I don't see the problem on my device. I started with 0910 qm stock fw, then progressed through upgrades including the AML 0921 using the flash tool that did have some fixes for AXP202 and since then onto the feiyu ROMs and flambe and CM10, AOKP and CM10.1 and I haven't had any battery issues. I wonder if the AML 0921 had some persistent changes on nand that were carried over - just guessing though.

Sent from my Novo7Flame using Tapatalk HD and CM10.1


AML 0921 and flash tool, these are the two things that distinguish from others.

Can you please post the link for 0921.TM and flash tool? Flashing steps will also be helpful.
Can I go back from 1031 to 0921 without any problem?

Thanks

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#9 Billcnz

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Posted 29 December 2012 - 05:34 PM

AML 0921 and flash tool, these are the two things that distinguish from others.

Can you please post the link for 0921.TM and flash tool? Flashing steps will also be helpful.
Can I go back from 1031 to 0921 without any problem?

Thanks

Sent from my Novo7Fire using Tapatalk 2

info for AML flash tool can be found here: [defunct link removed]

it's not a straight forward process like the normal procedure though so had a few people going around in circles and the 0921 came out before the TM screens. There is some 1022 official fw in this thread: http://www.slatedroi...20#entry454133. Unlike 0921 you don't have to use the flash tool but you have to wipe / factory reset and wipe media before and after flashing due to the different system partition size from the feiyu ROM.

You can reflash Feiyu 1031 at any time.

Sent from my Novo7Flame using Tapatalk HD and CM10.1

Edited by mrsburnout, 15 April 2013 - 12:44 AM.


#10 Ali DSD

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Posted 30 December 2012 - 01:44 PM

info for AML flash tool can be found here: [defunct link removed]

it's not a straight forward process like the normal procedure though so had a few people going around in circles and the 0921 came out before the TM screens. There is some 1022 official fw in this thread: http://www.slatedroi...20#entry454133. Unlike 0921 you don't have to use the flash tool but you have to wipe / factory reset and wipe media before and after flashing due to the different system partition size from the feiyu ROM.

You can reflash Feiyu 1031 at any time.

Sent from my Novo7Flame using Tapatalk HD and CM10.1


So Amlogic flash tool is not for TM users.

I recently switched to 1112.TM (official) , lets see does it solve the percentage problem .

#11 edwin2012

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Posted 01 January 2013 - 12:49 PM

I'm running kernel 20121211.tm with CM10.1 build20121229 +comp1.1 for around 6 hours now and looking at the battery history details this does not look promising... (graph is descending for a while but ascending after a reboot and descending again after some use).

Edited by edwin2012, 01 January 2013 - 01:31 PM.


#12 virus_9110

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Posted 02 January 2013 - 03:55 AM

Hello. I'm need help. My tablet Ainol novo 7 fire does not turn on, even in stock recovery and bootanimation. It happened when I surfed on internet,tablet unexpectedly freezed and I can see bootanimation. She repeated one minute and and after that she freeze and tablet is off. After that I can't turn on him and recover him. Please help.

#13 ainolpk

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Posted 02 January 2013 - 12:39 PM

Hello. I'm need help. My tablet Ainol novo 7 fire does not turn on, even in stock recovery and bootanimation. It happened when I surfed on internet,tablet unexpectedly freezed and I can see bootanimation. She repeated one minute and and after that she freeze and tablet is off. After that I can't turn on him and recover him. Please help.

"She freeze"???
"Can't turn on him"????


Your tablet is suffering from gender disorder!!!
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#14 9008

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Posted 02 January 2013 - 01:28 PM

So Amlogic flash tool is not for TM users.

I recently switched to 1112.TM (official) , lets see does it solve the percentage problem .


hi. does is solve battery problem? where can i download it? my flame battery problem makes me crazy :angry:

#15 9008

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Posted 02 January 2013 - 02:32 PM

i installed 20121211.tm it has not got google play store how can i install it? i will try battery issue and also tablet works better than feiyu1031

#16 Billcnz

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Posted 02 January 2013 - 09:05 PM

i installed 20121211.tm it has not got google play store how can i install it? i will try battery issue and also tablet works better than feiyu1031

Look at this thread for play store info: http://www.slatedroi...es?#entry471394

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#17 Ali DSD

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Posted 03 January 2013 - 04:29 AM

hi. does is solve battery problem? where can i download it? my flame battery problem makes me crazy :angry:



No, after using 1211.tm for a few days, the problem is still there, but now tablet shutdown around 30% .
I think Ainol should hire good Software Engineers team ( off-course they will be highly paid ). Or they can outsource the Software development (if they can not find competent enough developers in China) to any Asian country.

#18 Billcnz

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Posted 03 January 2013 - 12:24 PM

I copied this post from another thread, it worked for some people. I can't test as I don't have the problem:


Step 1. your tablet must be rooted.

Step 2. get any Terminal command line apps from google play

Step 3. in the Terminal apps type "su"(without quote) and [Enter] change user to root, then type the following command :

echo B820 > /sys/devices/i2c-2/2-0034/axp20_reg
(or actually "echo B8A0 ...") and reboot,
and if necessary
echo 0800 > /sys/devices/i2c-2/2-0034/axp20_reg

Make sure do this steps when full charge



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#19 9008

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Posted 03 January 2013 - 12:38 PM

thank you for your responses i have already installed it it is perfect but still battery issue...
its antutu benchmark score is 9533 which is great!

#20 hemoo

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Posted 05 January 2013 - 08:02 AM

"She freeze"???
"Can't turn on him"????


Your tablet is suffering from gender disorder!!!

Lol.it happens:D