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Hello
I had gone out to get a car charger for the XDA Exec. i went to the t-mobile shop and they gave me a car charger for the motorola V3 and said it would work.
i have not tried it, but my brother who has an imate jasjar tried it and it does not seem to work with his device.
both the XDA & V3 use a USB cable from the PC to charge them up, that made me think they could use the same car charger, what do you guys think?
u need to think about the voltage of the charger u have, you should never use a charger that was never designed for your device.
even if it is fractionally dfferent, this could cause anything from failure of your device to fire, etc. you should have got a charger from an o2 shop, I got one and it was only 15 quid. works perfectly and was designed for universal devices.
The main problem here is the current the charger will deliver.
I have 1 exec that will only just charge from an 850 m amp charger the 2nd exec wont charge at all. You really need a charger that will deliver 5v 1 amp to charge effectively.
I stuggled to find such a charger but the active holder from Brodit does the job superbley. i got mine from
www.gpsforless.co.uk
Regards
The Pilgrim
thanks for the replies
so it is the current specifications which is the problem!!
i geuss the voltage spec is nto a problem, since the USB outlet should guarantee volts between 4.75 and 5.25, correct?
i guess the comp based charging works, cause the computer can provided as many amps as required, correct?
but why would one xda charge up and the other wont.
resistor tolerances ??
what about the charging algorithm , once the battery charges up, what prevents the charger to push more juice into the xda exec. likewise with the ccmputerbasec charager?
Can i use a car charger meant for the t-mobile MDA Pro with the O2 XDA EXEC or with the i-mate jasjar, or are the specifications different?
the_pilgrim said:
The main problem here is the current the charger will deliver.
I have 1 exec that will only just charge from an 850 m amp charger the 2nd exec wont charge at all. You really need a charger that will deliver 5v 1 amp to charge effectively.
I stuggled to find such a charger but the active holder from Brodit does the job superbley. i got mine from
Click to expand...
Click to collapse
That's strange, true computer USB ports only deliver 500 mA and it appears to charge just fine, if very slowly, on one of those. Razr chargers are not entirely the same as regular USB chargers, the Razr uses the extra USB pin (mini has 5, regular has 4) to tell it what kind of device is connected, cradle, computer, etc. It's possible that the Uni chokes on that.
As an experiment, I hooked a 400 mA (specced) USB adapter to my MDA Pro, the charge light comes on. It's at 70% battery at 1:00 am local time. I'll check again a bit later to see if it actually charged.
[Edit: It's 22 minutes or so later and I've moved to 76%, while the PDA was otherwise turned off. That confirms that it's very, very slow. Also, the adapter was pretty warm, it may have been running over its rating.]
I'm not sure how much this experiment is worth though, I've got a near duplicate of this adapter with a different colour that's specced at 1000 mA (and in fact they're now selling the same outer plastic with a 2000 mA rating). If the insides are as similar as the outside, the other one's just underrated, but it's possible that the insides are actually different.
Re:Voltage, as far as I know, anything that uses a USB charger is 5V so should be intercompatible. This statement does not come with any express or implied warranty of fitness and I will not be replacing any devices you fry.
Still, though, most devices tend to run on "be liberal in what you accept" -- my Nokias charge on anything from at least 3 to 8 volts. I wouldn't be surprised if the uni is the same, but I won't be testing that out anytime soon. At least not without reloading the original rom first in case I'd need to warranty it.
xda_guy said:
what about the charging algorithm , once the battery charges up, what prevents the charger to push more juice into the xda exec. likewise with the ccmputerbasec charager?
Can i use a car charger meant for the t-mobile MDA Pro with the O2 XDA EXEC or with the i-mate jasjar, or are the specifications different?
Click to expand...
Click to collapse
All the universals are identical to a much closer look than simply charging. The only thing that's different there is the colour, a charger colour coordinated with an MDA Pro isn't with a jasjar.
The name 'charger' is really a misnomer. What 'chargers' actually do is provide a (semi-[1])constant voltage at a certain maximum number of amps, ie, they're *power supplies*. The actual charger which takjes care of the battery charging algorythm is integrated inside the Uni. All the 'charger' needs to do is make electricity of the kind that the *actual* charging chip inside is designed to run on.
[1] Most chargers, even original equipment let alone aftermarket, are highly crappily regulated.
Get one from a local orange store - 10 quid for a spv500 one, works great.
actually i tried to charge a second razr using my comp and it woudl not charge up? does this mean the current spec varies from device to device, even within the same device
if one messes up the uni by charging it using a charger from a different make, it is still under warranty?
hey jasper
The only thing that's different there is the colour, a charger colour coordinated with an MDA Pro isn't with a jasjar.
what do you mean by colour coordinated
The name 'charger' is really a misnomer. What 'chargers' actually do is provide a (semi-[1])constant voltage at a certain maximum number of amps, ie, they're *power supplies*. The actual charger which takjes care of the battery charging algorythm is integrated inside the Uni. All the 'charger' needs to do is make electricity of the kind that the *actual* charging chip inside is designed to run on.
does this mean that charging algorithm is actually within the phone itself, i mean when the phine is 100% charged, how does it know that it should not charge any more?
so there are 2 types of USB sockets, one with 5 pins and the other with 4 pins. did nto the standard USB have 4 pins?
is the 10 quid charger from the orange store meant for an actual spv5000? the t-mobile store gave me 2 chargers which they said were meant for the razr and the ysaid it would work just fine on the razr
re orange 10 quid charger - no idea. i read on a forum that someone else had got one and said it worked, so i got one too and it worked great.
previously I had used the supplied usb cable with a car adaptor and it couldn't keep up with running tomtom, so the battery would go flat. with this charger i can run tomtom and the device charges fine too.
thanks for the reply
you had received a usb cable with a car adaptor ? was this a unit which plugged into the cig lighter socket of the car
hi
this charger works with the exec and charges it quickly
http://cgi.ebay.co.uk/CAR-CHARGER-O...itemZ5849569917QQcategoryZ48674QQcmdZViewItem
xda_guy said:
thanks for the reply
you had received a usb cable with a car adaptor ? was this a unit which plugged into the cig lighter socket of the car
Click to expand...
Click to collapse
The cable was the standard one supplied. the car adaptor does plug into the cigarette lighter socket - one was supplied with a palm t3 car kit, another with an ipaq car kit. both never worked as previously stated (showed charging but failed to keep up with battery drain in use).
xda_guy said:
The only thing that's different there is the colour, a charger colour coordinated with an MDA Pro isn't with a jasjar.
what do you mean by colour coordinated
Click to expand...
Click to collapse
I mean that if you get a silver charger, same colour as the MDA Pro, it will not be a black charger, same as the Jasjar. So it may not look quite as cool, but it'll work just fine.
The name 'charger' is really a misnomer. What 'chargers' actually do is provide a (semi-[1])constant voltage at a certain maximum number of amps, ie, they're *power supplies*. The actual charger which takjes care of the battery charging algorythm is integrated inside the Uni. All the 'charger' needs to do is make electricity of the kind that the *actual* charging chip inside is designed to run on.
does this mean that charging algorithm is actually within the phone itself, i mean when the phine is 100% charged, how does it know that it should not charge any more?
Click to expand...
Click to collapse
There are three components that have to do with charging: First there's the battery. It's got four contacts (+, -, and two others) which means it's probably a smart or at least semi-smart battery, which has internal sensors for temperature etc, either directly wired to outside or with a small chip to multiplex the lot onto just 2 wires, then there's a chip inside the phone which does the actual charging, it probably knows how full the battery is by measuring the output voltage, and regulates charge current based on that and the temperature., and communicates that to the OS. Then there's the so-called 'charger' outside the phone, or the USB cable, which simply provides the raw electricity to work with.
so there are 2 types of USB sockets, one with 5 pins and the other with 4 pins. did nto the standard USB have 4 pins?
Click to expand...
Click to collapse
Standard 'large' USB ports, both the ones found on your PC (long rectangular in crossection, 'type A') and the ones like are on a printer (more squarish in crosssection, 'type-B') have 4 pins. There was at one time a mini-USB with 4 pins as well, bit that was never common and is highly obsolete. And then there's the regular mini-USB we have these days, which has 5 pins. It comes in three variants which look almost the same: Mini-B, which you get on things like digicams, external cardreaders, etc ('slave devices'), and on the end of the USB cables that came with your universal (since it acts as a slave device when hooked to a PC), then there's mini-A, which is for computers that can't fit a fullsize one (rare), and then there's mini-AB, which can be used by both mini-A and mini-B plugs, and is the physical port found on the universal. These should be used by PDAs that provide USB-Host functionality, that is, you can hook them to a PC and they'll act as a slave device, but then you can hook them to a car reader or external hard drive and they'll act as host. Unfortunately, while the Universal has the physical mini-AB port, it doesn't *actually* support USB-Host functionality.
thanks for the info on the usb connectors
I got this.
Works in your car AND in a standard wall outlet in case you dont have a laptop or computer around to do power over usb.
http://www.boxwave.com/products/versacharger/index.htm
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They even have an airplane adaptor in the case that your favorite airline has outlets...
I NEVER leave home w/o this thing...like EVER...
xda_guy said:
does this mean that charging algorithm is actually within the phone itself, i mean when the phine is 100% charged, how does it know that it should not charge any more?
Click to expand...
Click to collapse
When the battery reaches its maximum capacity the voltage dips slightly. the chargers in the phone detect this and stop charging.
Regards
The Pilgrim
xda guy
You can use your V3 car charger to charge your Exec. I do although it doesn't charge as fast as your mains charger or one designed specifically for it. It's something to do with the milli amps output.
However, it won't charge unless you plug it in with the clam Closed and the device OFF. You can subsequently open the clam and/or turn it on (for example if your running TT) and it continues to charge. If you plug the charger in with the device on, switch it off and it will charge (you can then turn it back on).
BTW - The V3 mains charger WON'T charge the Exec !!!
I use the one from Brodit, supplied by www.dsldevelopments.com and it works a treat. Never any problems, and Brodit gear is always top notch!
Ant
thanks for the replies
hey does the versacharger work with all mobile phones?
voltage of the battery dips slightly?
However, it won't charge unless you plug it in with the clam Closed and the device OFF. You can subsequently open the clam and/or turn it on (for example if your running TT) and it continues to charge. If you plug the charger in with the device on, switch it off and it will charge (you can then turn it back on).
Click to expand...
Click to collapse
hey how do you turn the exec off?
hey how do you turn the exec off?
Click to expand...
Click to collapse
ermmm, with the on/off button !
I tried to charge my Tilt today using the Car Charger that I got with it from AT&T but it isn't working. I accidently jammed my stylus into the mini usb port a few weeks ago andthen but it didn't look any different and nothing seemed to break off. It will still charge with my wall charger at home and will still sync with my computer. I know that the car charger is supposed to charge my phone faster but it should still use the same connections as my regular one..right? Could it be the ROM possibly? I can't test this right now because I am at work and my phone won't sync with my work computer.
Sorry if this is in the wrong forum please move if it is.
Check the cigarette plug in your car, sometimes it can be full with dirt on the connector in the car.
I had the same problem today and cleaned it out just with a screwdriver so that its connecting now.
Well the light on the charger is lit so I assume there is power going to it and it works with my mom's razr charger. The USB port actually looks dirty but I wouldnt know how to clean it out lol
bartimeus said:
I tried to charge my Tilt today using the Car Charger that I got with it from AT&T but it isn't working. I accidently jammed my stylus into the mini usb port a few weeks ago andthen but it didn't look any different and nothing seemed to break off. It will still charge with my wall charger at home and will still sync with my computer. I know that the car charger is supposed to charge my phone faster but it should still use the same connections as my regular one..right? Could it be the ROM possibly? I can't test this right now because I am at work and my phone won't sync with my work computer.
Sorry if this is in the wrong forum please move if it is.
Click to expand...
Click to collapse
I had issues with my Tilt not charging in the car, which turned out to be a weird issue with CardExport. I had the CardExport tray icon set to autostart, and my phone would not charge in the car - only when connected to a PC. Disabling the CardExport tray icon and doing a soft reset fixed it. Now if I need to use CardExport I just start it manually.
HTH
Check your mini-usb connector on the phone, if the bit in the middle doesnt seem level it won't charge at full speed
bartimeus - Did you ever find a solution to this? I have been using Igo on my phone in the car heavily over the past few days for long trips. I have 3 car chargers and all wont charge the phone (resulting in no loss of satnav :-S).
Oddly, my phone shows that it is charging - sometimes only for a few minutes, sometimes continuosly - but it doesn't.
I accidentally shoved my stylus in the USB port too about 10 months ago and i wonder if this is a result of that. Odd it charges from a PC by usb and mains though - but not via a car charger.
I found that any of the Cheap ass Chargers I used won't charge it. I'm waiting for my HTC made one to arrive so I can find out if there is an issue.
I read on a thread a while back about pin 4 and pin 5 need to be soldered together for the Kaiser to want to charge.
pharaohamps said:
I had issues with my Tilt not charging in the car, which turned out to be a weird issue with CardExport. I had the CardExport tray icon set to autostart, and my phone would not charge in the car - only when connected to a PC. Disabling the CardExport tray icon and doing a soft reset fixed it. Now if I need to use CardExport I just start it manually.
HTH
Click to expand...
Click to collapse
I have this problem but have never used cardexport... any known fixes?
JimmyMcGee said:
I found that any of the Cheap ass Chargers I used won't charge it. I'm waiting for my HTC made one to arrive so I can find out if there is an issue.
Click to expand...
Click to collapse
My car chargers are 'cheap ass' Ebay purchases. Please let me know how the HTC charger gets on.
Not sure if this is the case for Tytn II, my Asus P525 need to have the middle 2 pins (D+ and D-) short in order to charge.
jackleung said:
Not sure if this is the case for Tytn II, my Asus P525 need to have the middle 2 pins (D+ and D-) short in order to charge.
Click to expand...
Click to collapse
I vaguely remember reading that some people shorted Pins 4 and 5 and it worked.
JimmyMcGee said:
I vaguely remember reading that some people shorted Pins 4 and 5 and it worked.
Click to expand...
Click to collapse
I don't know how you come up w/ Pin5 as USB has only 4 pins (5+, Ground, D+, D-). Read the spec here: http://en.wikipedia.org/wiki/USB
I will do the mod on one of my adapter tonight and verify it
jackleung said:
I don't know how you come up w/ Pin5 as USB has only 4 pins (5+, Ground, D+, D-). Read the spec here: http://en.wikipedia.org/wiki/USB
I will do the mod on one of my adapter tonight and verify it
Click to expand...
Click to collapse
Look for Mini-B It has Five Connections. That's what I'm referring too.
JimmyMcGee said:
Look for Mini-B It has Five Connections. That's what I'm referring too.
Click to expand...
Click to collapse
Then it would be pin 2 and pin3 for D+ and D-.
Ok, let me share what I found so far and the result turns out to be very surprising. I have 3 different cigarette to usb adapter (yes, I got lot of gadgets to feed in my car. ). And the test are done w/ maximum backlight and A2DP music to my JVC BT-1.
1. Cheapo w/o current rating label, (I guess it's about ~500ma). D+ and D- shorted
2. Another cheapo rated w/ 650ma. D+ and D- NOT shorted
3. An expensive one w/ rated at 2A (yes, this is the only one w/ enough juice for my power hungry Dell Axim x51v). D+ and D- NOT shorted.
result: 1 = work, 2 = not work, 3 = not work.
Then I shorted both 2 and 3
result: 1 = work, 2 = not work, 3 = not work.
It seem shorten D+ and D- does not change the result. Just about to conclude I didn't prove anything and about to give up, and I try a different USB to mini-USB cable. It surprise me all of them are working!!!
From the pic below, the charging icon of battery status mean the cable is connected. Current w/ a plus sign mean the Tilt is being charge
Cable 1:
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Cable2:
Therefore, I conclude:
1. it turns out my AT&T Tilt are very picky about the USB cable quality.
2. For cigar to USB adapter, maximum support current and the quality may not very important.
3. We may or we may not need to shorten D+ and D- since I don't want to spend time to unshort them.
p.s. I still don't understand why cable 1 gives bigger charge on adapter 1 but refuse to charge on the rest, while cable 2 give consistent charge on all adapter. I re-test several times but gives the same result.
Short Pin 5 (+5V) and Pin 4 (unused). And tell me what happens.
JimmyMcGee said:
Short Pin 5 (+5V) and Pin 4 (unused). And tell me what happens.
Click to expand...
Click to collapse
The mini-usb plug is too tiny for me to work on it. I will pass it to whoever has the tool to test it.
Right, as I posted earlier, I have 3 cheap car chargers - 1 with integral cable and 2 that are just the adapter and require a separate cable. None charge my phone. A usb cable that works from my pc fails to charge in the car.
So, I bought a genuine HTC car charger. I fully expected this to work fine, but it doesn't. It does exactly the same as the cheapo chargers - My phone shows the amber charging light for a minute or two, then it goes out. No charging takes place at all. The battery icon shows charging all the time the cable is plugged in though.
My ciggarette socket is fine and supplies enough current to make the ciggarette lighter thingy glow hot.
/baffled.
chaps said:
Right, as I posted earlier, I have 3 cheap car chargers - 1 with integral cable and 2 that are just the adapter and require a separate cable. None charge my phone. A usb cable that works from my pc fails to charge in the car.
Click to expand...
Click to collapse
Do you have other USB cable to try?
Hey all, No i have not yet found a solution for this problem. I believe I have a genuine HTC charger or at least an AT&T one because i got it witha bundle with my phone from AT&T. I am looking at the USB plug and it seems to be bent down a bit on the right side as you are looking at it.
I think i might talk to my girlfriends cousin who works for AT&T and see if he can be awesome and replace it for me without me having to put the AT&T crap back on there for an actual warranty return.
still charges at home wall plug in and syncs with my computer just fine
This is how i get around this happens, though it sucks if you're using it as a navigation device. When it stops chagrining through the car adapter, I leave the cable plugged into teh phone and the cigarette/power adapter and do a soft reset. This seems to clear it up somehow and it starts charging.
This post will show you how to MOD an un-official Samsung USB wall charger into one that will enable full speed charging on Samsung Galaxy S phones.
8 $ ebay cheap wall battery charger power output specs:
350 mA battery charging speed - doesnt matter...
800 mA USB port.. THIS IS WHAT YOU WANT!! more the better. nice if the phone would use all of it... Need AC Mode... (thats what this post is for!)
Samsung wall USB charger is only 750mA! AND it will set AC mode.
The theory behind it is with samsung galaxy phones and "official chargers":
if the middle 2 data pins on the usb, while getting 5v to the outer 2 pins it tells the phone that it is an *official samsung* charger and enables full speed charging.
without the middle 2 pins connected (with or without data flow) will not charge at full speed. even if you supply 800mA it will only charge around 350mA
well there have been posts of cable hacks to do this or adapters... ha! tape and tinfoil... or hack the cable apart! And you cant use the cable with the PC anymore!
heres my mod... bend 2 pins.. DONE! solder if you know how for better connection!
***only use this charger for samsung phones, not all USB devices will like this, -may dammage some- as the samsung phone is PROGRAMMED to know what to do if the 2 data pins are shorted out***
Phone confirms AC charging NOT USB NOW!!
Now i can leave my Samsung Charger upstairs, and this one downstairs.
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You know how long it takes to charge an extended battery on USB mode? almost 5 hours! or at 350 mah in the battery charger? almost 7 hours!
I was able to charge my extended battery (says 2500mah) from 8% to 100% in about 2 hours 45 min over USB cable (AC mode) with the screen off. In the official samsung charger it was a little over 3 hours. just in the battery cradle it takes around 5-6 hours. Very much improved!
Good guide. I did the same modification to my Verizon car charging cable. I don't have Verizon, but I swapped an iPhone car charger with a verizon user who got rid of his Motorola Android.
This mod works on any charger. The device will always display "Charging(AC)" and this enables full charging capability.
I modded my cable by taking apart the microUSB connector and dropping a bit of solder between pins 2 and 3 on the back side of the connector. It works great.
Do not do this on a cable which may be connected to a PC. If the PC is older and does not have overcurrent protection, it may fry the USB Power Supply.
You could also use one of those short usb extender cables that come with some usb dongles. I did that with one of mine and it works great. Don't even have to take the cable apart just carve out a small part of the plastic connector between the pins and bridge it with solder. Or use a conductive pen- haven't tried that though.
Wow i'm so lost, so does this apply to the vibrant...
You know maybe I have had my foot up my ass for sometime then..
I ALWAYS charge my phone with the USB charger connected to the computer and it seems to take forever...
You must forgive me but I always leave my phone charging on my PC everynight and have actually lost the AC power wall plug portion...
Will connecting this through the USB of the computer also only supply the 350mA instead of the full 800mA like your saying, or will the computer always deliver the sexy amount?
Thank you sir, you are a genius?
jwleonhart said:
Wow i'm so lost, so does this apply to the vibrant...
You know maybe I have had my foot up my ass for sometime then..
I ALWAYS charge my phone with the USB charger connected to the computer and it seems to take forever...
You must forgive me but I always leave my phone charging on my PC everynight and have actually lost the AC power wall plug portion...
Will connecting this through the USB of the computer also only supply the 350mA instead of the full 800mA like your saying, or will the computer always deliver the sexy amount?
Thank you sir, you are a genius?
Click to expand...
Click to collapse
Most of PCs provide up to 500mA on single USB port or on pair of ports, haven't heard about mainboard which doesn't throotle it and let power drain go higher.
However, you can mod usb cable with 2 male and 1female connectors, that kind for powering external hard drives.
Here is a picture of the pinouts in a usb cable..
Now obviously you have the 5V, Ground, and data, but then where would you add in more power?
jwleonhart said:
Now obviously you have the 5V, Ground, and data, but then where would you add in more power?
Click to expand...
Click to collapse
The talk about connecting the pins 2 and 3 is only an indication to the phone. Normally, usb ports from computers, etc. will only provide 500 mA of current. Typical wall adapters provide 1000 mA of current. Samsung phones will normally only draw the smaller amount of current, unless pins 2 and 3 are shorted, which tells the phone to charge at the full rate of 1000 mA.
So pin 1 still carriers power, it just carries more power when connected to a source capable of providing the power (e.g. most wall adapters), and pins 2 and 3 tell the phone to accept the increased power.
jwleonhart said:
Wow i'm so lost, so does this apply to the vibrant...
You know maybe I have had my foot up my ass for sometime then..
I ALWAYS charge my phone with the USB charger connected to the computer and it seems to take forever...
You must forgive me but I always leave my phone charging on my PC everynight and have actually lost the AC power wall plug portion...
Will connecting this through the USB of the computer also only supply the 350mA instead of the full 800mA like your saying, or will the computer always deliver the sexy amount?
Thank you sir, you are a genius?
Click to expand...
Click to collapse
if the 2 data pins arent joined the phone WILL NOT receive anymore than 350. this tells the phone "im an official charger, take more!"
if you are going to mod a cable to have the 2 data pins joined, make sure the 2 pins shorted on the phone end and NOT THE PC END of the cable, and NOT BOTH EITHER. shorting the data pins on the computer side can blow your usb port.... or more.
Thanks
Thanks, Worked For Me!
Same thing you can make via kernel by adjusting max8998 regulator driver. I've done it in my Galaxian kernel
Do you mean to build a kernel that has different settings for the USB resistor input? What/where was the specific change you made?
TRusselo said:
Do you mean to build a kernel that has different settings for the USB resistor input? What/where was the specific change you made?
Click to expand...
Click to collapse
Voltage regulator and the charging current part: max8998-private.h, a file that contains charging values in mA:
Code:
#define MAX8998_ICHG_90 0
#define MAX8998_ICHG_380 1
#define MAX8998_ICHG_475 2
#define MAX8998_ICHG_550 3
#define MAX8998_ICHG_570 4
#define MAX8998_ICHG_600 5
#define MAX8998_ICHG_700 6
#define MAX8998_ICHG_800 7
Battery driver part: s5pc110_battery.c and defined AC and USB charging rates (modified by me to 800mA when on AC and 550mA on USB):
Code:
if (chg->cable_status == CABLE_TYPE_AC)
max8998_write_reg(i2c, MAX8998_REG_CHGR1,
(MAX8998_TOPOFF_10 << MAX8998_SHIFT_TOPOFF) |
(MAX8998_RSTR_DISABLE << MAX8998_SHIFT_RSTR) |
(MAX8998_ICHG_800 << MAX8998_SHIFT_ICHG));
else if (chg->cable_status == CABLE_TYPE_USB)
max8998_write_reg(i2c, MAX8998_REG_CHGR1,
(MAX8998_TOPOFF_25 << MAX8998_SHIFT_TOPOFF) |
(MAX8998_RSTR_DISABLE << MAX8998_SHIFT_RSTR) |
(MAX8998_ICHG_550 << MAX8998_SHIFT_ICHG));
One more thing in i9000 kernel sources: drivers/usb/gadget/android.c
Code:
#ifdef CONFIG_USB_ANDROID_SAMSUNG_COMPOSITE
/* soonyong.cho : This value of max power is referred from S1 */
[COLOR="Red"].bMaxPower = 0x30, /* 96ma */[/COLOR]
#else /* original */
[COLOR="YellowGreen"].bMaxPower = 0xFA, /* 500ma */[/COLOR]
#endif /* CONFIG_USB_ANDROID_SAMSUNG_COMPOSITE
from where I removed the condition to make it look like that:
Code:
[COLOR="YellowGreen"].bMaxPower = 0xFA, /* 500ma */[/COLOR]
BEFORE:
AFTER:
Now that's the kind of stuff we like to see!
NOW ENGLISH IMAGE (non android related)...
Is there any particular reason why you did not move USB speed to match the PC speed? Was it to avoid drawing too much power from your USB port?
TRusselo said:
Is there any particular reason why you did not move USB speed to match the PC speed? Was it to avoid drawing too much power from your USB port?
Click to expand...
Click to collapse
Yes and no, because single USB port cannot deliver more than 500mA, but if you use two ports simultaneously, you are able to use full 800mA charging current which is limited by the kernel driver so there is no way to charm the phone.
If you have any USB 3.0 ports those are able to go up to 900mA from a single port
I just tried this and it worked perfectly, thanks! Very easy soldering job.
EDIT: Used my $8 radioshack iron, it was plenty. No need to break out the Hakko station for this.
some kernel devs on ICS SGS project seem to think the above kernel change to up the USB mode to 500mah (less than AC mode) could cause the battery to explode, or damage the phone, or fry the USB ports of the computer..... and the batteries *like* being charged slower anyway... lithium ion batteries... but its all "simple chemistry" according to "one of them".. ignoring simple electronics...
i dont know where to start on how many things are wrong with what they think.... but I am not a kernel compiling god like them..... so I am no-one to tell them different.... (in their eyes).
making the suggestion of the above kernel change. led to a 20 minute bashing session of how i am wrong.
i just wanted to suggest, and leave. not really caring if they liked it or not. but ignorance is a powerful foe.
anyone wanna explain for me?
makes me re-think donating to people i dont know.
TRusselo said:
some kernel devs on ICS SGS project seem to think the above kernel change to up the USB mode to 500mah (less than AC mode) could cause the battery to explode, or damage the phone, or fry the USB ports of the computer..... and the batteries *like* being charged slower anyway... lithium ion batteries... but its all "simple chemistry" according to "one of them".. ignoring simple electronics...
i dont know where to start on how many things are wrong with what they think.... but I am not a kernel compiling god like them..... so I am no-one to tell them different.... (in their eyes).
making the suggestion of the above kernel change. led to a 20 minute bashing session of how i am wrong.
i just wanted to suggest, and leave. not really caring if they liked it or not. but ignorance is a powerful foe.
anyone wanna explain for me?
makes me re-think donating to people i dont know.
Click to expand...
Click to collapse
So now you know why you didn't saw any info about my interesting finding... ^^
Sent from my GT-I9000 using Tapatalk
we need to have software devs that understand hardware...
im too much in the middle. lol
The project-Adding internal USB for other devices (HUB,micro SD,FM,flash-storage,etc...).
We should have a few deferent options to connect USB internally. This thread should cover them all.
I really want to find a easy solderless method(plug/clips) I have a few ideas but would need to find the female and male connectors for the front camera or maybe soundboard connectors.
or
maybe disconnect the micro USB from the ribbon and run it up to the hub then back to the micro USB connector from the HUB that's one reason for the hub, so we can add a micro SD, a rear camera and the last port (HUB only has 3 ports active, it might be possible to find a different HUB that has 4 ports but this one only had 3) for ether some more flash storage or to hook up the solderless mod to mother board.
We can use the micro USB connection at bottom of the mother board a couple different ways. We could use both the data and power from the connector. We could also just use the data +/- from the micro USB connector and use the power from a different power source like the 7.4V from the battery and drop it down to 5V but none of the wires are 7.4v there is two running at 3.7v, if we could find the 7.4v on the board or a connector somewhere this could be done
Some pics
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http://s10.postimage.org/6zg4euc21/N7_cable.jpg
Does this mod actually work or is that last picture just what it might look like?
atticusmas said:
Does this mod actually work or is that last picture just what it might look like?
Click to expand...
Click to collapse
Not yet, Just trying to find some other wiring options and parts before I wire it up.
Would this guy be similar to the nexus tablet?
nabitablet .com/specs/nabi2
amazon. com/Fuhu-NABI-NABI2-NV7A-7-Inch-Tablet/dp/B008DBI5RI/ref=sr_1_4?ie=UTF8&qid=1342981188&sr=8-4&keywords=nabi+2+tablet
Maybe the board could be close, find out how to use the microSD slot on the nexus 7 tablet?
(sorry about the chopped up url's, I guess I can't post links yet)
I Found this little USB HUB and it fits perfect.
This is it before it got striped
Still just in mock up and not connected yet, but it does still close up fine. So I'm pretty sure a hub is a go(for me anyway) and still have room for some flash storage that will go where the rear camera should have gone or just beside the hub
Has anything happened with this project?
Camping for a few days with the family, then back at it.
Wow that's awesome man! Keep on the good work!!
Envoyé depuis mon Nexus 7 avec Tapatalk
What do you mean by an issue with remounting when you use the power from the USB? I had read somewhere about someone shorting two pins to make the mod work but you could no longer charge and would need a switch to deactivate the short to charge it. If any switch is needed to change anything physically then I was thinking the tiny type that you press with a pen head or similar, that is recessed.
I hope you make progress when your back on it. I ordered the usb otg cable and have some tiny micro sdhc readers that slide into a usb slot that are as thin as a reg. sd card. I figured I could solder wires onto one and mount it for the card reader. I was thinking to use hot glue or similar between the soldered connections for safety since it isnt easy to get factory type solder joints all the time on small stuff (even though I am decent at soldering).
I hope someone can come up with the software hack needed to be able to actually mount the micro sd and install to it like any other tablet can.
Thanks for the pictures and work you are doing, I am sure many are watching :good:
Just a few comments on this project:
If you put a hub or device in then it requires that you operate the tablet's USB interface in host mode.
Normally, something supplies power and will not accept power for charging when in host mode.
There are hacks to get around this, but I'd see if I could get this all working externally before I started modifying.
You could end up with your hub idea working find, but you are unable to charge the tablet.
When you do lay the cables in, twist the data pair and leave the two power leads straight.
This looks awesome! Can't wait to see the tutorial if one becomes available, these devices get me in trouble!
Sent from my Nexus 7 using xda app-developers app
Have been watching this thread with great interest as well. Indeed, I always only lurked on XDA, this piqued my interest enough to actually join.
Fingers crossed for OP!
Sent from my Nexus 7 using xda app-developers app
Hub fits I just need to come up with a 5V power somehow got the Data and ground figured. Can someone come up with any ideas to create 5V power, maybe some fancy circuitry to bump the power from battery to 5V?
iAppleDev said:
Hub fits I just need to come up with a 5V power somehow got the Data and ground figured. Can someone come up with any ideas to create 5V power, maybe some fancy circuitry to bump the power from battery to 5V?
Click to expand...
Click to collapse
What model number hub did you use, does that have the USB OTG built in to it?
I am going to ask a few people in another type of forum about the voltage, a few on there know more than I on this topic. What is the battery stock voltage? I first was thinking resisters but I think we would need to know the exact current going through it to determine the right size. I am searching for tiny DC voltage regulators to see what I can find also, but wasn't sure the stock voltage. Here is some info on DC voltage regulators youtube.com/watch?v=GSzVs7_aW-Y&feature=fvwrel I cant post links yet so it doesn't have the www . The video talks about regulating DC voltage to power 5volt usb devices.
Do you think anyone will have a custom ROM or other hack so we can mount and install to the micro SDHC card once this mod is complete? Because that is what I want before I go this far.
Glad your back at it though! Thanks for your work on this.
Normally the 5V power to external devices is fed from a charge pump in the USB PHY interface chipset.
Some non-standard implementations only supply 3.7V battery power.
3.7V may/may not be enough for your hub and SD card.
If you are using 3.7V to a standard USB/SD card adapter, you might try bypassing the LDO in the adapter.
Also, many devices can only host about 100 mA.
Both hubs and USB/SD card adapters can be current hogs.
I think that some actually experimentation is called for before taking a Dremel tool to your tablet.
Renate NST said:
Normally the 5V power to external devices is fed from a charge pump in the USB PHY interface chipset.
Some non-standard implementations only supply 3.7V battery power.
3.7V may/may not be enough for your hub and SD card.
If you are using 3.7V to a standard USB/SD card adapter, you might try bypassing the LDO in the adapter.
Also, many devices can only host about 100 mA.
Both hubs and USB/SD card adapters can be current hogs.
I think that some actually experimentation is called for before taking a Dremel tool to your tablet.
Click to expand...
Click to collapse
Wouldn't it be best to us a non powered usb hub to split the usb connection? I doubt a small keyboard would use much and as far as I go, I would only use the usb for a small case sized keyboard, charging the device and the micro sdhc card/reader.
So is the battery only 3.7 volts? I was thinking it might be more and we needed to step down, so we need to step it up for the micro sdhc reader?
eBandit078 said:
So is the battery only 3.7 volts? I was thinking it might be more and we needed to step down, so we need to step it up for the micro sdhc reader?
Click to expand...
Click to collapse
It's actually two 3.7v Li-Poly cells set up in series for a total of 7.4v. As pointed out (rather rudely) in a prior post, the leads aren't spliced on the pack itself so that a 5v USB input can charge the batteries. My old Acer A100 actually had the batteries spliced so that a 12v charger was needed. It had very weak battery life, but the upside was that the 12V charger would take it from 15% to 100% is a little less than an hour.
Renate NST said:
If you put a hub or device in then it requires that you operate the tablet's USB interface in host mode.
Normally, something supplies power and will not accept power for charging when in host mode.
There are hacks to get around this, but I'd see if I could get this all working externally before I started modifying.
You could end up with your hub idea working find, but you are unable to charge the tablet.
Click to expand...
Click to collapse
Very good points. You may be happy to know that the USB specification recently provided a means for charging an OTG device while in host mode. It's called "Accessory Charger Adapter". See Chapter 6, and in particular Figure 6-2 from the specification:
www.usb.org/developers/devclass_docs/BCv1.2_070312.zip
If you could nail this down, you might solve a bunch of challenges with the +5V supply at once. Not sure what it would take to implement though. A cursory search for dedicated ICs didn't produce anything for me.
Renate NST said:
When you do lay the cables in, twist the data pair and leave the two power leads straight.
Click to expand...
Click to collapse
:good: Second that suggestion.
So this device runs on 7.4V dual Li-ion batteries?
Is there a separate charger input or only over the USB?
Hi all,
I have had my 7 for a while however I left it for several days after it ran out of juice and I'm now experiencing the issue where it cannot charge via usb. I have an appropriate battery charger and intend to juice the battery up slightly whilst disconnected from the pad to give it enough power to rise from the dead and charge normally.
Has anyone looked into which of the 6 connections coming from the battery do what? There are obviously 2 red, 2 black, a yellow and a white. Is there something like a 5v, 12v and data connection??
Can someone educate me to which connections I can apply voltage to, to charge it please?
I would rather go down this route if possible rather than going through warranty as I have no backup of the items currently on my nexus.
Any help would be very appreciated.
Cheers,
Rob
What little I know about Li Po cells/batteries is:
The nexus 7 has a single cell battery rated at 3.7v - no 5v or 12v
Charging outside the Nexus is DANGEROUS. Protective bags are used to hold LiPo cells whilst charging (and transporting them).
Where the wires enter the cell there is a thin section that will be a PCB with protective electronics that will monitor the temperature of the cell.
Your red/black pairs COULD be a pair for charging and a pair to power the Nexus and the white and yellow ???????
Your charger should have this info in its instructions.
Two remarks to finish DON'T DO IT and search Youtube for "LiPo overcharge"
I've done it with phone batteries when I've been at a mates or something and I've ran out of battery and not had my charger.
Its safe, provided you give it the correct voltage, to the correct pins lol, and don't try and fully charge. Give it 50% of its normal charge time max. But since you only need to get into the boot loader to properly power off so it will charge again you're only speaking about a quick ten minute charge..
As for the two pairs, its maybe a 2 cell battery.
White and yellow are likely temperature sensor.
Sent from my Nexus 7 using Tapatalk HD
knuckles1978 said:
I've done it with phone batteries when I've been at a mates or something and I've ran out of battery and not had my charger.
Its safe, provided you give it the correct voltage, to the correct pins lol, and don't try and fully charge. Give it 50% of its normal charge time max. But since you only need to get into the boot loader to properly power off so it will charge again you're only speaking about a quick ten minute charge..
As for the two pairs, its maybe a 2 cell battery.
White and yellow are likely temperature sensor.
Sent from my Nexus 7 using Tapatalk HD
Click to expand...
Click to collapse
I'm facing exactly the same problem, and no "normal" work-arounds seem to be working for me, I just can't get into the bootloader. So it is either trying to recharge it myself or buying a battery..
So given the fact that you have done it with other devices, could you please explane how you would start with all this? Here is a picture of of the nexus 7 battery connector, if it would help you:
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(the picture is from ifixit).
I was thinking about molesting the usb cable of my htc and use the black and red cables to charge the battery (I suppose that a USB output can not put a to high voltage to the battery?), but I do not know which red/black poles to use on the battery connector..
Thank you very much in advance!
Erwin
Ive never done one with two pairs like that, but here's what I'd do to get enough charge to boot at least. I would connect my positive from the charger to one of the battery connectors reds, and connect the negative to one of the blacks (obviously lol). Give it 5 minutes only, then swap your negative charger wire onto the other black of the nexus. Give it 5 minutes only again.
Then swap your positive charger wire over to the other red of the nexus and repeat the process, keeping the positive on that red and connecting the negative to each black for 5 minutes.
You only need enough charge to boot, so this will be fine. Also, keeping it to 5 minutes each keeps it safe.
An even better way to do it would be wait until tomorrow until I can get a hold of a multimeter and i would check to see how the pairing is, then you could do it without the guesswork. But if you can't wait, I've told you the way that i would do it.
Sent from my Nexus 7 using Tapatalk HD
knuckles1978 said:
Ive never done one with two pairs like that, but here's what I'd do to get enough charge to boot at least. I would connect my positive from the charger to one of the battery connectors reds, and connect the negative to one of the blacks (obviously lol). Give it 5 minutes only, then swap your negative charger wire onto the other black of the nexus. Give it 5 minutes only again.
Then swap your positive charger wire over to the other red of the nexus and repeat the process, keeping the positive on that red and connecting the negative to each black for 5 minutes.
You only need enough charge to boot, so this will be fine. Also, keeping it to 5 minutes each keeps it safe.
An even better way to do it would be wait until tomorrow until I can get a hold of a multimeter and i would check to see how the pairing is, then you could do it without the guesswork. But if you can't wait, I've told you the way that i would do it.
Sent from my Nexus 7 using Tapatalk HD
Click to expand...
Click to collapse
I'm trying to be patient for almost a week now, so one day (or more, if you need them) will not be a problem Take as much time as you need, I'm already thankfull that you are willing to look into it!
All the best,
Erwin
ErwinP said:
I'm trying to be patient for almost a week now, so one day (or more, if you need them) will not be a problem Take as much time as you need, I'm already thankfull that you are willing to look into it!
All the best,
Erwin
Click to expand...
Click to collapse
I'll be able to get a multimeter tomorrow for sure, that way i can check it out properly for you. The other way is safe and would definitely work though, but its no problem for me to check it out.
Sent from my Nexus 7 using Tapatalk HD
Again, thank you already in advance, I hope this gets me out of trouble. What an inacceptable bug, bah.
One additional question though, if you don't mind. What are your thoughts of using the stripped usb cable an my laptop to deliver that little bit of battery juice? I'm good with my hands, can replace every part of your bike and am able place a new smartphone screen with my eyes closed, but I just don't know anything about the real hardcore electronics
All the best,
Erwin
ErwinP said:
Again, thank you already in advance, I hope this gets me out of trouble. What an inacceptable bug, bah.
One additional question though, if you don't mind. What are your thoughts of using the stripped usb cable an my laptop to deliver that little bit of battery juice? I'm good with my hands, can replace every part of your bike and am able place a new smartphone screen with my eyes closed, but I just don't know anything about the real hardcore electronics
All the best,
Erwin
Click to expand...
Click to collapse
It is not a bug. Your tablet has entered a sleep mode to prevent t the battery from being damaged. I have previously posted the procedure to enable it to charge and wake again. Search through my recent posts for the fix- I unfortunately can't link it right now due to time constraints.
ETA: Plug your N7 into the charger and immediately press power and volume down to get into the bootloader. Once there, use the volume key to scroll to Power Off Device and then press the power button. After it powers off, unplug it and then plug it back in. It should then charge normally.
Sent from my Nexus 7 using Tapatalk HD
najaboy said:
It is not a bug. Your tablet has entered a sleep mode to prevent t the battery from being damaged. I have previously posted the procedure to enable it to charge and wake again. Search through my recent posts for the fix- I unfortunately can't link it right now due to time constraints.
Click to expand...
Click to collapse
I'm sorry, but this is a bug and not a feature of the device protecting you. If the device runs out of battery, it should do what every other tablet and smartphone does: shut down. And it should shut down 'way before' the battery is completely out of power, so that it still has a fair amount of battery capacity to at least once initate startup, notice that the battery is too low to continue and shut down properly. Of course, if you try to restart the device several times whilst it doesn't have any battery power left, then you are damaging your device. But than you are an idiot as well
Look at wat happens when you are working on your N7 and power comes to 0%. Indeed: it will shut down properly and you will be able to charge it without any problems. However, if battery comes to about 10% and you do not shut it down manually but leave it just sitting there, the device will do what it normally does: it goes to (deep?) sleep. However, even deep sleep consumes battery and inevitably you will reach the point where the battery is at 0% (seen by the android device). But instead of waking up and shutting down the device properly, it just stays into its deep sleep, consuming power and finally undercharging your battery making the device totally irresponsive. This is what I call, a bug.
I know now that I should either shut down or recharge my N7 when I come to the point of 10-15% battery. But hey, once you learn that, it is too late, this is why I'm here
najaboy said:
ETA: Plug your N7 into the charger and immediately press power and volume down to get into the bootloader. Once there, use the volume key to scroll to Power Off Device and then press the power button. After it powers off, unplug it and then plug it back in. It should then charge normally.
Click to expand...
Click to collapse
Thank you very kindly for your help, but as stated before, I have tried everything already. Including a whole evening trying to get the timing right to see the android bootloader following the solution you mention. But it doesn't give anything but frustration. So I understand why you point to that solution, but that is one of the first solutions that comes up if you google my N7 phenotype. Again, thank you kindly, but for now I do not see any other solution than trying to get an inital voltage in that battery manually.
Best regards,
Erwin
Same issue has happened to me and I can not even enter the bootloader...
What is your status on this issue?
SubZero5 said:
Same issue has happened to me and I can not even enter the bootloader...
What is your status on this issue?
Click to expand...
Click to collapse
did anyone charge it manually out of the nexus ? I've verified that the black is - and the red is + with a multimeter. battery reads .47 with multimeter. If you guys are going to charge it 5 minutes per pair, definitely get a multimeter to read the positive and negative coming out of the 5v chargers.. also, make sure that it's about 5 volts cuz some are about 6? I dont' know if having too high of a voltage will fry it.. i do know from experience that some usb chargers are 5 and some are 6 volts and some are even slightly more. I'm talking about getting a transformer that goes from usb to the circular out put head..
Same problem here. Someone on another thread was suspecting the magnetic cover causing problem and I'm using one too. Anyone having this problem NOT using a magnetic cover?
I know this is thread is a few months old.
donnygg said:
Same problem here. Someone on another thread was suspecting the magnetic cover causing problem and I'm using one too. Anyone having this problem NOT using a magnetic cover?
Click to expand...
Click to collapse
I have a similar problem and my n7 has never had a case.
Update
I hooked the battery up to a usb port using the out side read and black wires, red was + black was - charged for about 1 minute via pc usb power while monitoring with a dmm. the tablet now charges normally.
Charge manually
chevyowner said:
I know this is thread is a few months old.
I have a similar problem and my n7 has never had a case.
Update
I hooked the battery up to a usb port using the out side read and black wires, red was + black was - charged for about 1 minute via pc usb power while monitoring with a dmm. the tablet now charges normally.
Click to expand...
Click to collapse
I did charged the battery manually.
For about 1 minute for each pair of red/black.
Not to bump an old thread but manually charging indeed fixes this problem. Used a multimeter to take a reading from one nexus 7 and then cut up an old usb and hooked it up to the ends of the multimeter and placed them on the first 2 points. Charging manually up to about 3.7ish should be enough to accept a charge.
Thanks guys saved buying a new battery.
i have a bit of life after manually charging, is it important to do both pairs of black and red? I have 2 batteries and now the nexus flashes an empty battery logo up when i hold the power button, its better than before as nothing came up at all but still wont boot up
I just charged my battery up manually using a proper Li-Po battery charging unit, left it charging at 2.5A until it hit 4.0V. No problems.
I did not charge up both pairs. I believe this is unnecessary: see first image in this thread: http://forum.xda-developers.com/showthread.php?t=2311799
The pairs of red and black are actually soldered together, so it doesn't make a difference which pin you apply the voltage to.
I would be worried about charging the battery directly with a 5.0V supply (ie. USB voltage). Don't do it if you can avoid it.
If at any point when charging a battery directly you notice it getting hot, stop immediately.
External charging nexus 7 batteries
Use the black - and the red + wires to charge .Charge the outer red and black wires ,I use a 5 volt charger since these batteries are rated at 3.7 v + or - .5v Charge the batteries to a voltage reading of 4.2 volts this will be a full charge.Please Note you will be charging this battery with out a protection over voltage or temp sensor system. If the battery is bad ,will not take charge due to damaged cells, or is overheated while charging they will burst apart.Charging with out protection circuits can damage batteries and also harm yourself.You do this at your own RISK.
@knuckles1978, @androiddeveloperg, @mr portugal, @chevyowner, @VanquishUK
Thanks guys!!
You saved my Nexus 7!
I charged the battery with my computer's usb port and a multimeter connected, let it charge to 3.90V (with power), and it booted up again
Now I have to get it to 100%, as it still shuts down after booting..
Sent using my nexus⁴ running Mahdi 2.8 with Xposed and hells-Core B64
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