|
Post by Admin on Mar 13, 2016 8:47:04 GMT
Hi there, Thanks for all the info on this mod, I have done the battery delete and all seems fine, except I am having the same problem as Justin. I cannot get the tablet to go into Timur's Rom mode via OTG while connected to 12v. Again when I switched back to the battery it worked fine. Anyone have any ideas on why this might be? Thanks Graeme Hi Graeme, I never really heard of this problem before, are you using the 2013 or the 2012 N7, when you say not go into ROM mode what do you mean exactly ?
|
|
|
Post by gstiles on Mar 13, 2016 14:51:01 GMT
I have a 2012 and a 2013 that I have tried this with. When connected directly without the battery neither device seems to pick up USB host mode and do not turn on and of with ignition/turning the car off.
|
|
|
Post by Admin on Mar 13, 2016 15:38:40 GMT
I have a 2012 and a 2013 that I have tried this with. When connected directly without the battery neither device seems to pick up USB host mode and do not turn on and of with ignition/turning the car off. when you turn off the ignition does the battery symbol on the N7 still have a lightening bolt through it as if it is showing it is still charging ?
|
|
|
Post by phatbuddha56 on Mar 14, 2016 18:06:39 GMT
It seems to work pretty well. Like I said, my SNR is a little sketchy. I used WAY more hook up wire than I needed to. Since I didnt want to short myself. So I might trim a foot or so off, and see if it helps clear up the signal some. I have a feeling its the length of hook up wire though, so I might even move the antenna closer to the tablet/center of dash. Hey was your GPS antenna mod done on the 2012 or 2013 version? Btw I'm liking your home screen setup. What app is that your using? As for the no battery mod, I haven't had any further problems with the tab suspending and my OTG and hub always been working with no problems. My OTG is connected to the Mini-Box PSU set at 5.4v if that's any help
|
|
|
Post by JEGsGarage on Apr 15, 2016 18:59:54 GMT
Wow... I havent been on here in a bit. Didnt realize there were messages. Sorry!!!
Im running Apex launcher. The background is a PNG file that I made in photoshop. Then I use desktop visualizer (app) to make invisible buttons over each area that I want to be a "button".
I still want to try this again, but I must have fried my little power board because I cant get any power out of it now. Which is a bummer.
Justin
|
|
|
Post by veryshort on Apr 16, 2016 10:53:46 GMT
Hi Guys .. I'm having a problem with this battery mod .... ok I have removed the battery and hard wired a 5v supply ... off that supply I have taken a +ve feed to a small micro switch which in turn feeds the +ve side on my micro USB connector that is plugged into the charging port . I have old motorise tilt housing { see link www.youtube.com/watch?v=BKyo7VciumM } from my car that use to have the japanese nav system installed { I have removed the whole lot to put my N7 2012 into it } The micro switch is triggered once the tilt housing reaches a certain point this supply's power to the USB charge port { why did I do this ..... I didnt want my N7 to be powered on all the time } and in turn should wake up the tablet . The problem is that by removing the battery and supplying it with a direct 5v the charge port does not trigger , I have proved the system works with the N7's battery installed ... My only conclusion is that for the charge port to trigger it is looking for some sort of battery resistance to start charging .has anyone else found this on either of the versions of the N7 ? my details ... N7 2012 Groupner Android 5.1.1 { lollipop } no custom rom or Kernal Any help would be great thanks guys . Cheers Andrew W
|
|
|
Post by JEGsGarage on Apr 27, 2016 12:17:48 GMT
Hi Andrew. I, and others, have experienced the same thing I believe. I think you are correct with your theory. Using a power supply, we're sending over 5v to the tablet. It thinks the battery is at 110%. More than the stock battery at full charge basically. The charge circuit is probably looking for something under 100%. Even after being on for a second, the battery is technically at 99.99999%, but still enough for the charge circuit to kick on.
I would like to drop the voltage supplied down to the 4.78 range, or whatever the battery puts out and see if that works.
I could be way off base there, but for the life of me, I couldnt figure out why the tablet would care what was providing the power. Its the same voltage, to the same spots as the battery provides. Yet it acts different. The only variable is the actual voltage we're using.
Justin
|
|
|
Post by Admin on Apr 27, 2016 17:32:48 GMT
Perhaps the circuitry on the 2012 N7 battery is different from that on the 2013 and that difference could be the cause, I never did it with 2012 so couldn't really add anything more.
|
|
|
Post by veryshort on Apr 28, 2016 9:24:47 GMT
Hi Andrew. I, and others, have experienced the same thing I believe. I think you are correct with your theory. Using a power supply, we're sending over 5v to the tablet. It thinks the battery is at 110%. More than the stock battery at full charge basically. The charge circuit is probably looking for something under 100%. Even after being on for a second, the battery is technically at 99.99999%, but still enough for the charge circuit to kick on. I would like to drop the voltage supplied down to the 4.78 range, or whatever the battery puts out and see if that works. I could be way off base there, but for the life of me, I couldnt figure out why the tablet would care what was providing the power. Its the same voltage, to the same spots as the battery provides. Yet it acts different. The only variable is the actual voltage we're using. Justin Hi Justin , Great I'm not alone ! Ok its a single Li-Po{ lithium polymer} Cell from my days flying RC planes/helis etc and dealing with Li-po's a single cell doesnt like to go below 3.6V per cell when fully charged the voltage is around 4.2v per cell so my thinking is we would have to trick the charge circuit into thinking the voltage was low and hence when it gets its micro USB input it starts charging .Ok so I'm thinking we have to drop the 5v down to something like 3.9v to trigger the charge circuit .Unfortunately I'm not an electronics engineer we would have to come up with a virable step down voltage regulator that we could set at 3.9v and then test it from there . As you say my theory could be way off .I really don't want a LI-Po cell left in my car they are very volatile and wont like big temperature changes I'm also thinking that if you have any sort of car insurance your policy could be voided should anything happen to the car that can be traced back to your N7 Install . cheers Andrew W
|
|
|
Post by joel61 on May 11, 2016 9:04:16 GMT
Hey boys, I'm about to jump into this no battery mod on my 2012 N7 If you guys are interested here is my install www.youtube.com/watch?v=iniACymrgSUSo basically my only concerns are having the tablet detect when the microusb has power (accessory power to charge port). Have any of you got this working yet? Other than that I am ready to go with doing this mod
|
|
|
Post by Admin on May 11, 2016 17:18:00 GMT
Hey boys, I'm about to jump into this no battery mod on my 2012 N7 If you guys are interested here is my install www.youtube.com/watch?v=iniACymrgSUSo basically my only concerns are having the tablet detect when the microusb has power (accessory power to charge port). Have any of you got this working yet? Other than that I am ready to go with doing this mod I cant help you with this as I only have the 2013 N7 ..
|
|
|
Post by luciano on May 14, 2016 8:07:30 GMT
Hi First of all i like to thanks all of you guys for providing so many tips for transforming our beloved nexus into a car Infotainment system. Now lets get back to the "bugs", my problem is that powerring my N7 2013 through the back battery connector ve- ve+ via 5v usb power the tablet only bootloops. Here are the scenarios: - 5v to the battery connector = bootloops - 5v to the battery connector + 5v via microusb = works fine = battery shows 100% - 5v to the battery connector + 5v via microusb = boots ok then if i disconnect 5v microusb port = the tablet restarts and again bootloops. I'm thinking that the PM circuit doesn't like the 5v supply through the battery connector and shuts down the tablet because of temp. protection sensor that is built into the battery pcb. Now i'm going to add a stepdown to from 5v to 4.2v to make the PM thinks that the batt is fully charged and temp is within parameters, any thoughts from you guys? Btw i'm using ElementalX kernel and cm13 latest. Edit: Here is a nice tutorial for nexus 7 2012 www.drive2.ru/l/4273715/ forum.androidbg.com/showthread.php?tid=73920 google translate Thanks! Today news! The usb cable that was connected to the battery pads was 28 AWG and 1.5m = 0.637229 ohm / cable resistivity = 25% power loss = me dumb Now is powering ok with a 22 AWG....
|
|
|
Post by joel61 on May 23, 2016 0:31:12 GMT
Just a few updated from the users over at xda regarding the N7 2012
"Just got an email notification that this thread was active, I was the dude who got it going by powering up the battery controller board. There was a problem I found in that I think the software used to track the battery level wound down the indicated charge over a couple of days. A disconnect and reconnect of the usb power feed fixed the reading with a "FULL" charge level when it came up. I had this going for a month on the benchtop with no problems. Do NOT try to power the battery controller board from the base USB port (or pogo for that matter) while it is connected to the main board. I think there's some earth loop issues and I killed mine. Happy Hacking!" - dribbleboy "So are you saying powering your batteries circuit board (without the battery) and "charging" the nexus through the proper usb port at the same time killed your tablet?" - Me " Death was when I multimetered out where the voltage was coming into the backplane on the nexus mainboard (from the bottom usb port) then soldered wires from those points to the back end of the battery ++ -- " - dribbleboy " Oh, so if I understand correctly, just powering the tablet via 5v usb from where the battery would normally be in the back and then using the charge port on the bottom to detect if the car is on. My tablet should be fine with that?" - Me "I had mine powered and connected to usb ok but personally from losing my tab I would only have it being powered from one source. Also remember that when you pull the power when it's running you're crashing an OS that wasn't meant to stop this way." - dribbleboy Source: forum.xda-developers.com/showthread.php?t=2311799&page=3So i'm really not sure what I can do, as I dont want to damage my tablet. Does anyone know how to convert 5v to 4.7v?
|
|
|
Post by Admin on May 23, 2016 8:00:32 GMT
Just a few updated from the users over at xda regarding the N7 2012
So i'm really not sure what I can do, as I dont want to damage my tablet. Does anyone know how to convert 5v to 4.7v? I know there are no issue's like this with the 2013 N7, so it may be worth considering upgrading (sometimes you can get them quite cheap on ebay) You can also get some variable power supplies, I think if you check ebay perhaps
|
|
|
Post by luciano on May 23, 2016 8:16:01 GMT
Use a galvanically isolated dc-dc converter ( do no use cheap chinese converters) to power the battery pcb, i use "SD-15A-5" from Mean Well, that has a trimpot to lower the voltage down to 4.45v which by the way works great for me. Using a standard psu or usb car charger will give you ground loop and you will need another audio usb dac or audio isolator circuit to fix the high pitch noise. Common ground between the car (a very noisy powe source) and the nexus it's not a good ideea anyway!
|
|