Kossuth | # 41 | 2014-10-14, 05:16 | Report

Actually I started to drain the battery for calibration controllably by maxing out the current drain and planning to cut the drain down to 20-50mA from the over 300-500mA by the time that the battery comes down to low voltages around 3400mV, but as always life happens and I had to be somewhere else and the battery drained in a flash at the end.

Cursing my failed attempt to calibrate I connected the charger and planned to try the routine again tomorrow. But when I booted the phone I noticed the chip had calibrated itself after all. I was almost sure It didn't have the needed 15secs below the 3248mV to set the EDV1 to 0. Has the procedure changes because of the BME replacement or was I just lucky? Normally with max drain my batteries havent lasted over few seconds below the treshold.

Ofcourse, I'm not complaining, I'm happy with this. I'm just pointing my experience out, so to possibly learn more.

alexporta | # 42 | 2014-10-14, 20:55 | Report

If I insert a fully charged battery (from the wall chargher) a battery that have done the calibrating cycle, my N900 doesn't start, it blinks the white light and turn off... it only start if I insert the charghing plug, then I can see the battery is ok and calibrated...

can I revert the BME pls?

Estel | # 43 | 2014-10-14, 21:35 | Report

Luck - the procedure can't be changed, as it's the chip itself that calibrates itself after 15 seconds below threshold.

BTW, I know you pain - sometimes, I discharged my 3Ah cell with >1A current in the N900 (flashlight, video recording, GPS, FM transmitter, 3G with 1KB pings every 2 seconds, etc) for the same purposes, and boy, how many times I forget to tune it down before shutdown...

BTW, just for the record - when discharging battery with artifically high rate (i.e. much quicker, that you would do normally), you're going to get lower max capacity value - because capacity is relative to discharge current (and in our case, even discharge pattern, as we're using variable discharge current along the way). Sometimes it's beneficial, as it gives you safety margin - for when you think you're approaching 6% during normal usage, you have - in fact - few more left. Or a "buffer" for heavy usage. Anyway, I like to have capacity rounded a little down, instead of up, and then being surprised when I need to do some heavy usage late in discharge stage...

/Estel

Kossuth | # 44 | 2014-10-15, 07:10 | Report

If you are referring to this post giving you something about not existing, then your repositories might be messed up, check them. If you are referring to some other post, can you give a bit more info, for example copy paste from x-term or other more specific info on your action to revert to the stock-BME and the errors you are receiving.

biketool | # 45 | 2014-10-15, 07:24 | Report

OT warning...
In the last posts by Android808 he was looking for someone with a working Z to run petittrack so he could do the full conversion of the source form QTE to QT4. http://www.qsl.net/n1vtn/petittrack.html
any chance you can install and PM him?

alexporta | # 46 | 2014-10-15, 07:59 | Report

thanks for your answer
it says me "BME version0.8.55+0m5" was not found

Kossuth | # 47 | 2014-10-15, 08:41 | Report

Did you copy/paste the command? I tried the command with -s tag (to simulate it, not to install) and it said that the file was found from downloads.maemo.nokia.com.

If I misspelled the filename, I got the error that the version was not found. Can you try to copy/paste the command and copy/paste the contents of the x-term then here? If the command is right, and you still get the error, you should check that the standard nokia and ovi repositories are enabled in HAM.

BTW I'm not sure, but you might want to read the whole thread again, where the quote came from, as there might be some other packages that have to be downgraded also. They might get downgraded automatically with the BME, but I can't be sure about this. There is always risk of screwing up your N900 when up/downgrading core system packages manually.

malfunctioning | # 48 | 2014-10-15, 14:50 | Report

Thank you for letting me know about this, biketool.

I just checked the OESF forum and I only saw a few posts about petittrack on the 5500. I will contact Android808 and see how I can help!

Kossuth | # 49 | 2014-10-16, 07:50 | Report

Maybe OT, but this got me thinking, does the chip itself power down with the OS, or is it possible that it stays awake for at least 15 sec after shutdown, so it calibrates itself and I have actually myself corrupted the calibration before, by connecting the changer too fast? Also the scenario could be that when I drain the battery with high current and it drops down below the shutdown limit, the batterys voltage bounces little bit back just over the 3248mV after the phone is shutdown thus corrupting the calibration. Or just as you said, luck!

Estel | # 50 | 2014-10-17, 11:29 | Report

Chip memory is kept using power from main battery (negligible) or bupbat (the same one that keeps clock). It requires much less power than real-time clock, so even in the cases where you lose hour/date instantly on removing battery, your calibration data will persists for a ~10-20 seconds longer, allowing to replace batteries without need to re-calibrate.

Removing battery for longer (without working bupbat) results in chip losing data, and resetting itself to default 2048 mAh full charge capacity.

Device must be powered on for calibration to take effect. In fact, shutting it down for too long/too often during single discharge cycle, invalidate VDQ (valid discharge quality) flag, resulting in NOT taking that discharge cycle into account for calibration. Charging to full sets VDQ flag to 1, again.

/Estel