Timur's Kernel - USB ROM - Most popular thread on Rootzwiki
Posted 23 December 2012 - 01:40 AM #13
I've found the USB charging rate to be insufficient at maintaining charge just simply with the screen + wifi + BT on.
My N7 stays at "100% full" all the time, with screen + wifi + BT turned on. After an over night sleep (no power supplied), the battery goes from 95% to 100% in just a few minutes. Rather than trying to supply more power, you should try to find the root cause of the issue. A single misbehaving app can easily ruin all power management. Does your tablet run warm? What's on top of your power consumer list?
If you urgently need to activate fast charging, with the OTG adapter being connected to the tablet, you could try to short the Data pins using a manual switch. I don't think it will, but, you never know, this *might* harm your devices.
- 0 Likes
Posted 23 December 2012 - 01:45 AM #14
A fixed install means a car install or similar where you dont have access to remove otg and replug,and when in use it has constant power.
It's what costs $2,480 if you have BMW do it for you.
Edited by Timur, 23 December 2012 - 03:59 PM.
- 0 Likes
Posted 24 December 2012 - 01:11 AM #17
Oh...they're talking about 'physical' installation duh....haha I was wondering how it differed from a regular kernel installation and why I never heard of it......
OTG host mode is by definition just a temporary endeavor. Whatever you do in OTG mode, you have to stop doing it after a while and go charging. My kernel allows you to use USB slave devices AND to keep your tablet charged at the same time. So you can keep using your USB devices as long as you want.
The default (or mobile) variant of the kernel provides USB host mode + charging functionality, but will switch to OTG mode, whenever external power goes away. When you pull the OTG adapter, when using the mobile variant, your N7 will behave just like a normal Nexus 7. It's usually a good idea to provide new functionality, without taking away existing functionality. But there are cases where this is not true. The "fixed installation" variant takes OTG functionality away. It never sends power down to slave devices. This allows you to more easily put your tablet to deep sleep mode, when external power goes away. Your tablet will then keep it's charge over long periods of times and it will be ready to immediately serve you, as soon as external power comes back. And because both variants are available for Android and CM, there is a total of four kernel variants.
Note: I just updated the two Android 4.2.x variants (now: 2012-12-23) in order to fix an infrequent crashing issue. The two CM 10.1 variants (2012-12-19) are not affected by this and have not been updated.
Edit: @farhanito, CIFS is enabled in all variants. Can you elaborate on your use case a bit?
Edited by Timur, 24 December 2012 - 01:41 AM.
- 3 Likes
Posted 24 December 2012 - 02:38 AM #19
Well, this has been a well known problem on N7 since 4.2
Also happens with other kernel that supporting cifs as well. Something Google did
Using CIFSManager app, it says mounted, but shows empty folder on any file manager apps.
Tried mounting manually using terminal emulator, mounted, but still inaccessible with other apps.
Nexus 10 also have the same problem...
Sent from my Nexus 7 using Tapatalk 2
Edited by farhanito, 24 December 2012 - 02:45 AM.
- 0 Likes
Posted 24 December 2012 - 02:50 PM #20
Thank you for all your work!
I plan to install my Nexus 7 in my car (like many people). I'm planning on using a powered USB hub with a DAC, harddrive, external bluetooth GPS, HID type keyboard that will utilize car steering controls, and so forth.
The USB hub I'm planning on using will have a 20 minute shut off delay so that when I shutoff the car, it will still have power for 20 minutes. Theoretically, I was planning on having the power to the N7 tied to the ignition. I was doing this so that all the devices would still function for a while after the car was off. For example, the GPS wouldn't lose its lock at the gas station, or when I pull into my garage, I could kick off an rsync to make sure my music collection is up to date.
When I simulated this outside of the car in testing, the USB devices did not react well when the power was cut to the N7. The N7 didn't seem to be able to charge after (or at least I saw no icon for it) and the devices flicker, but seem to come back sort of okay (external HD gets detected as sdb1 instead of sda1. Annoying but probably fixable).
I've tried both kernels and am trying to understand what behaviors currently exist in each, and if there is anything I can do to leverage what work you've already done.
I'm trying to avoid running the N7 off of a hot wire in the car (always on, draining battery). It might be feasible I guess. I've seen this device last well over a week in airplane mode.
- 0 Likes