PBD REPORT FORM

TEST CONFIGURATION:

BOOT DEVICE: eMMC
MLO: BN 1.2 built by fattire (MD5: a2c9a23efdbe05a40e0066500c5cfea1)
U-BOOT: BN 1.2 cyan build by fattire (MD5: c3db4062d1e67d50a382245471c1cef8)
KERNEL: uImage 2.6.32.9 from OC 5/23
OVERCLOCKED?: to 1200
GOVERNOR: Conservative
SYSTEM: CM7 Nightly 86
PBD: NO
TEST COUNT: 2x- once with "untimely" u-boot and once with "cyan". Each time nc shut off at ~4%
TRIED REVERTING TO OLDER HC/CM7: NO
TRIED WIPING CACHE/DATA?: NO
DID IT WORK? N/A
PREVIOUSLY INSTALLED:

☐ Stock 1.0
☑ Stock 1.1
☑ Stock 1.2
☐ Nookie Froyo (any)
☐ Honeycomb (any)
☑ CM7 2.29 (any)
☐ CM7 2.32 beta 3
☑ CM7 nightlies > 84 (or whenever .32 appeared)

NOTES: I have dualboot setup on my nook with stock 1.2 installed on parts 9/10. Installation steps: Formatted /system(ext2), /data(ext2) and /cache, Installed stock 1.0.1 then updated to 1.2, setup dualboot partitions, moved 1.2 to dual boot parts, formatted /system(ext4), /data(ext4) and /cache, then restored CM from backup. I often switch between CM7 and 1.2.

BOOT DEVICE: eMMC
MLO: ?
U-BOOT: Whatever came with N87
KERNEL: 2.6.32.9 OC 5/23
OVERCLOCKED?: 1200
GOVERNOR: Conservative
SYSTEM: CM7 N87
PBD: No
TEST COUNT: 1x
TRIED REVERTING TO OLDER HC/CM7: No
TRIED WIPING CACHE/DATA?: No
DID IT WORK? N/A
PREVIOUSLY INSTALLED:

CM 7.0.3 Stable.
Stock 1.1

EDIT + NOTES: Battery finally died at 4%. I went near or below 3,000mv when it happened.
I had 13% with 3606mv. Voltage started free falling once I hit under 5% battery, I watched it go from around 3400 to 3060 all within the 4% range, right before it died, was trying to screencap when it died on me. I was a little over 12 hours off charger, I took it off at 96%-ish.
It seems 3000 to 3050mv is that cutoff point.

Originally Posted by skwalas

Well I'll be damned. It is for sure a calibration issue. Somebody Googled these batteries and read that they could not go below 3050 mv safely. I got pbd repeatedly just a few minutes ago at 20%... and 3000 mv.

Put the charger in and juiced it up a couple percent (showed 3600mv with charger in), unplugged, and let it run down again. Shutoff at 20% and 3000mv. I was able to replicate this multiple times. I already know that my 100% of scale is always right around 4200mv so it seems as if the 0% of scale is out of alignment.

How to recal the 0%?

Yep, my pbd happened at ~3-3.2V. Seeing as some people are reporting only ~10%-20% at ~3.6V, seems like our batteries were SEVERELY depleted. I hope they were not damaged because of that :/

I'm letting it run down now. Will post my u-boot, MLO et al. when/if it reaches 3.3V.

I think it would help if people starting finding our their voltages when or near their battery dies. Seems to be a pattern developing.

This is odd, my 100% is now right around 4000 mV and I know for sure it's been closer to 4200 before :/

Originally Posted by Animec

This is odd, my 100% is now right around 4000 mV and I know for sure it's been closer to 4200 before :/

I have noticed that the meter will read 100% a while before the "n" light on the cable will go green, further pointing to a calibration issue. Perhaps that's your case?

Originally Posted by I Am Marino

I think it would help if people starting finding our their voltages when or near their battery dies. Seems to be a pattern developing.

Here ya go, I got down to 4%, went to plug it in, and it shut down right before I got there. I got a screenshot of the 3041mV I believe. When my Nook comes back on (showing the charge screen right now) I will upload the shots.

Here is the datapoints I got 18-4%


18% 3568
17% 3573, 3566
16% 3563
15% 3538
14% 3562
13% 3557
12% 3565
11% 3505
10% 3508
9% 3501
8% 3499,3490
7% 3482,3475
6% 3390,3382,3356,3336,3321,3302
5% 3279,3256,3232,3198,3158,3123,3101
4% 3101,3041

A majority of this was sitting at battery booster screen watching at full brightness and with screen timeout set to never, so the cpu was pretty much idle.

It's real scary (and it's not Halloween!) I just finished a battery discharge test where I monitored the voltage and percentage as the battery was used up. The plot as a pdf is below:

http://dl.dropbox.com/u/22355237/NookBattery.pdf

Look at the rapid drop-off in voltage below 40% to 2860 mV at an indicated 34%. No wonder we are seeing PBD if others have the same problem!

I was watching the voltage drop before my eyes. I actually shut it down at the 2860 mV, and I can't turn it on again (I'm at work) - no charger.

Something is very wrong with the calibration... At an indicated 34% the battery is dead, deceased, gonzo, perished, pushing up daisies......

Edit: n87 - OC523 - data taken with Circle Battery widget.
If you can't see the plot - here's the data:
86 3917
84 3886
79 3839
76 3795
70 3758
67 3751
58 3696
46 3639
40 3604
37 3556
35 3503
34 3271
34 3172
34 2861

Originally Posted by derekr

It's real scary (and it's not Halloween!) I just finished a battery discharge test where I monitored the voltage and percentage as the battery was used up. The plot as a pdf is below:

http://dl.dropbox.com/u/22355237/NookBattery.pdf

Look at the rapid drop-off in voltage below 40% to 2860 mV at an indicated 34%. No wonder we are seeing PBD if others have the same problem!

I was watching the voltage drop before my eyes. I actually shut it down at the 2860 mV, and I can't turn it on again (I'm at work) - no charger.

Something is very wrong with the calibration... At an indicated 34% the battery is dead, deceased, gonzo, perished, pushing up daisies......

Edit: n87 - OC523 - data taken with Circle Battery widget.
If you can't see the plot - here's the data:
86 3917
84 3886
79 3839
76 3795
70 3758
67 3751
58 3696
46 3639
40 3604
37 3556
35 3503
34 3271
34 3172
34 2861

If you look at my post above yours, yeah, def a calibration issue, mine dropped out @ 4% 3041mV

ps, I would switch axis on the graph 0-100% bottom to top, 4000mV to 2400mV left to right

Originally Posted by Ronin3178

If you look at my post above yours, yeah, def a calibration issue, mine dropped out @ 4% 3041mV

ps, I would switch axis on the graph 0-100% bottom to top, 4000mV to 2400mV left to right

As you wish :
http://dl.dropbox.com/u/22355237/NookBattery2.pdf

however, let's discuss this over a beer sometime - which is the independent variable here? I think the first plot shows the precipitous voltage drop-off in a more graphic fashion... But, as always, your wish is my command

BTW - MATLAB won't let me (simply) reverse the x-axis order...