yashsingh1/xdaforums huggingface dataset:
[Hardware Hacking General] djbxp:
USB D+ / D- Signalling for USB and AC charge modes.​

After some measurements and tests i have the following infos to share with you all.

FOR ANDROID DEVICES:

If you apply 5V to the Vcc+ and ground the other 3 wires (D-, D+ and ground) so all of them have 0V = ground, then device is going to have USB mode supply.

If you apply 5V to the Vcc+, and connect ground and leave the D- and D+ wires on air (without connecting anything - insulate them), then device is going to have USB mode supply.

If you apple 5V to Vcc+ , connect the ground, and any different voltage values on D- and D+, the device is going to have USB mode supply. You can do it with voltage dividers or pass D- and D+ signals through different resistors (over 60K Ohm).

If you apply 5V to vcc+, connect the ground and give same voltage to D- and D+ , the device is going to have AC supply mode. In order to have the same voltage on D- and D+ you have to connect those together (green and white - middle pins on PCB interfaces), BUT YOU HAVE TO LIMIT THE CURRENT through a resistor connected to +Vcc 5V. (over 60K Ohm). So you go from +Vcc 5V, connect a resistor over 60K ohm, and have the other resistor end attached to D- and D+ all connected together.

FOR APPLE DEVICES:

For apple devices you don't have much of a choice. In order to charge any apple device you have to supply with voltage dividers the Data pins D- and D+ with specific voltages, and of course the +5V Vcc and ground. The specific voltages is 2,6V on D- and 2,1V on D+.

You can achieve this with 4 resistors , 2 resistors on 2 voltage dividers between 5V and ground. 56K and 47K is proper values. The larger resistor gets more voltage on it with respect to the ground, so if you connect 5V --> 56K in series with 47K and ground, the middle point of the resistors is going to be the 2,1V with respect to the ground and if you connect 5V--> 47K in series with 56K and ground, the middle point is going to be 2,6V with respect to the ground. So you give 2,6V (2nd case) to D- and 2,1V (first case) to D+.

TESTED ON IPOD 2ND, 5TH, IPHONE 3G / 3GS, IPAD 1st.

Peace.
[Hardware Hacking General] Entropy512:
This configuration is not advised. It is not covered as part of any particular standard. It could possibly damage a device.

No reason to ever configure a device this way - of course a dumb charger that only connects V+ and GND will effectively be this configuration.

No reason to do this for any non-Apple device.

This is excessive. All you need to do is connect D+ and D- together - no need for resistive voltage dividers.

The ONE exception are Samsung Galaxy Tab devices - these expect D+ and D- to be held to 1.2 volts by the charger. If you use high enough resistor values, you can set up the divider to provide 1.2 volts to a Tab, but easily be overridden by the "short detection" mechanism used by other devices to detect dumb chargers. 33k pullup 10k pulldown is known to work well.

Original source: http://www.ladyada.net/make/mintyboost/icharge.html
[Galaxy S I9000 General] Faz3r86:
Hi Guys,

Just joined so this is my fist post, just watched the noob video before joining so please be gentle, my post maybe repeated, so here goes.....

So I followed this path in getting my Samsung Galaxy S i9000 on Jelly Been:-

1. Updated to the latest firmware XXJW4

2. Installed the custom rom from the following link [http://xdaforums.com/showthread.php?t=1820578]

First off, hats off to the developer, this is a very good rom, it's fast, responsive and very easy to use. The rom is built with the function to update it with OTA which is a huge plus. The developers last update of the rom [v1.4.0] is even better, however in the latest update he removed the trebuchet launcher :confused:.

The reason why I prefer trebuchet launcher is because unlike the touchwiz launcher when you reboot the phone, apps that are stored on the SD Card, their icon do not revert to the andriod icon (something that keeps happening when I have touchwiz launcher as my main launcher). Also apps that are on the home screen, that are stored on the SD card, appear on home screen after a reboot if you use the trebuchet launcher but not with the touchwiz launcher.

Now the workaround I implemented when using touchwiz launcher (only launcher the developer provided) are:-

1. Once the device is up after a reboot, connect the device to a computer, Turn on USB Storage, then Turn off USB Storage.. This causes the phone to re-scan the SD card of Apps, Music etc... But this option isn't very practical

2. Install the app Appkik [https://play.google.com/store/apps/details?id=com.diune.appkik2&hl=en], and kill TouchWiz Home process, this will cause the launcher to reload again and then display the apps icon correctly.. Now this option is quicker, but could cause the launcher to become unstable, saying that, since implementing this option, the launcher has crashed 5 times today..

So The question is:-

1. Is there an alternative way of fixing the issues with regards to displaying apps icon correctly when using touchwiz launcher? e.g an app that can restart the touchwiz launcher safely

Thanks

Faz3r86

P.S Please guys don't offer the solution - move the app to the internal storage. As you guys know the internal storage isn't very big and I want to avoid storing apps in the internal storage as much a possible. Also I know that I can probably install a different launcher, but I wanted to keep the rom I installed as close to as possible to the developers release.
[Galaxy S I9000 General] AlwaysDroid:
If it is cm10 based, it probably has the hold back button to kill app. Kill launcher with that and it will restart it. Also for media scan I think you can use dev tools to re scan.
[Galaxy S I9000 General] Faz3r86:
Thanks for the tip

Thanks for the tip, that seems to have helped, just wish the devleopers for touchwiz launcher fix this issue, according to other posts, others suffer from the same issue :mad:
[Galaxy S I9000 General] FjarrKontroll:
That hasn't been implemented in Jellybean yet (to my knowledge) due to some issues. I hope it gets added soon though, there are a lot of times when an app starts making noise/using data that I want it immediately killed.
[AT&T Samsung Galaxy S II SGH-I777] beforedenied:
Hello, i am wondering if anyone knows of a kernel that supports USB OTG, and if MIUI Jellybean supports USB OTG. I just bought a OTG cable from ebay and am waiting for it to arrive. I know that the phone supports it out of the box, and that some kernels support it. But i have no idea if MIUI or Android 4.1 is supported. Thanks!
[AT&T Samsung Galaxy S II SGH-I777] Pirateghost:
I can't wait for the development on this project!

/sarcasm

Raise yer mizzenmast and swab 'er poop deck!
[AT&T Samsung Galaxy S II SGH-I777] Noz85:
Should be a good one :good:
[AT&T Samsung Galaxy S II SGH-I777] jsmith8858:
Pretty sure they all do.
[AT&T Samsung Galaxy S II SGH-I777] Phalanx7621:
This sounds an awful lot like a question...does anyone know by chance if there's a question and answer section this could have been posted in.....?
[AT&T Samsung Galaxy S II SGH-I777] drowningchild:
this should be posted in Q&A not dev...

but every kernel/rom -should- support OTG, i use it occasionally never have had issues, besides using not FAT32 FS, but thats easily fixed with apps and i think siyah even supports mounting NTFS otg to /mnt/ntfs
[AT&T Samsung Galaxy S II SGH-I777] RatusNatus:
Where's everyone?:eek:
[AT&T Samsung Galaxy S II SGH-I777] Phalanx7621:
I don't know where everyone else is, but I'm in yer closet.
[AT&T Samsung Galaxy S II SGH-I777] 122ninjas:
I feel most questions end up in general

Sent from my SGH-I777
[AT&T Samsung Galaxy S II SGH-I777] androidobsessed:
Oh you're here too? I didn't even notice you there
[AT&T Samsung Galaxy S II SGH-I777] VECTUS:
Moved to the appropriately named question and answer section...
[AT&T Samsung Galaxy S II SGH-I777] beforedenied:
Sorry friends, totally thought i had posted in Q and A, but thanks for the quick reply. :)
[AT&T Samsung Galaxy S II SGH-I777] jaoropez:
Just got a sgs2 today, was wondering about OTG, is it working on any roms? thanks!
[AT&T Samsung Galaxy S II SGH-I777] Pirateghost:
i guess you didnt bother to read this thread did you?

it has already been stated that its the kernel that controls it. go look at the kernel threads...FFS
[Nexus S General] VOLTAGEROCK:
OK, after being so annoyed with the Navigation on this phone not working, I finally found a fix that is working for me and I am in shock that what I did produced a working GPS. First, anyone who doesn't know how to take apart the black cover (not the battery cover) do a search. Next, after removing the cover, the GPS Antenna without a doubt is one right next to the power button. I found this out by putting a piece of electrical tape over every gold connector that touches an antenna, then closing the black cover, turning on the phone, running gps test, and after trying different spring connectors, I noticed I had the correct one when the app GPS Test couldn't locate any satellites. Next, I also noticed that on the inside of the cover that I took off, the one that requires six screws, there is a silver looking strip that is supposed to make contact to the connector that has a full metal top part, so when the cover goes back on, the silver strip must make contact to this negative grounding harness top. I added a bead of solder to the silver strip on the inside of the black cover so that I knew it was making contact. I believe that this is a source of everyone's problems with navigation. That strip must be a shield and the design doesn't look like it makes good contact to the connector's ground metal plate. You'll see what I mean when you open the cover.

Next, while I had the cover off, I wrapped a 30 gauge wire around the gold spring pin that connects to the GPS antenna and ran that wire down the side of the phone right along the PC Board in hopes that it extends the antenna. I just ran it like 3 inches and remember, I ran it down, not up. The GPS antenna already goes up. I put a tiny bead of solder on the wire where it contact the gold spring contact that is attached to the PC Board so that it does not come off accidentally. And believe me, it is really simple. You cannot mess anything up. Just a dab of solder is all it takes.

I put the black cover back on, and then ran the GPS test app and at one point I had 12 satellites read and used with a 7 foot accuracy!!! Next I went to the Navigation app and started playing around with different addresses and my navigation WORKED!!! I am still in awe three days later. I drove from New Jersey to Rhode Island yesterday and had the Nav running for the entire trip. Only one time did I get a small circle about the size of a half inch which lasted for 4 seconds. At that point, I was driving though a forest type side road with limited sky view.

Please try this fix for anyone who has Navigation issues with their Nexus S and let me know if it fixes it.

Dan
[Nexus S General] sublimaze:
Awesome. Samsung should have hired you before they released the Nexus S and 1st-gen SGS phones. My Captivate never had reliable GPS. I might as well have had Ray Charles giving me directions.
[Nexus S General] evcz:
Funny thing is Google nexus phones are bugged...

Nexus one multi touch bug

Nexus s compass not working...

I think the issue here is with whoever was choosing and picking the hardware that would have powered a nexus...

HTC and Samsung do not surprise me... But Google not testing the compass on a flagship phone before releasing scares me :-\

Luckily my gps works fine (i9023 here) but the broken compass create a lot of troubles with gps navigation as very often the phone thinks to be driving in the reverse direction...
[Nexus S General] albundy2010:
The nexus one digitizer wasn't a bug. Just a crappy digitizer. It worked as it meant to. It sucked but wasn't a bug.

The GPS and compass issues for the nexus s are different as well. Some devices have crappy ones and apparently don't work. My GPS and compass works perfect on the other hand. Always has
[Nexus S General] MRsf27:
I don't have problems with navigation, even tho i hardly ever use it. However, this compass thing; I downloaded an app called Smart Compass and it works really well... Where I know it's north, the compass points north and so on. but mind you, I got my phone after companies stopped selling it so I might've gotten the last of the good batch
[Nexus S General] DmA81:
Could you post a photo of the finished fix so I can check if I'm going to fry something :D ? Thanks !
[Nexus S General] X1111:
@VOLTAGEROCK:

post some photos for better help if it's possible, before and after modifications please

thanks in advance
[Nexus S General] VOLTAGEROCK:
I will but gimme a day or two. All I know is I'm on day five and its still working!
[Nexus S General] nexustechseeker:
wow

Sent from my

RESSURECTED Nexus S

CM10 NIGHTIES :cool:
[Nexus S General] VOLTAGEROCK:
I should have at the time of doing it, but I didn't know what i was doing was going to work!! Now I have to take the phone apart again, but you give me a reason to hook up my Touchstone from the Pre while the phone is open and accessible. I will do my best to put the pics up in a timely manner and in the meantime, if there's anyone out there, go to the iteardown fix it (i think that's what its called) and look at the video or pics of the Nexus being taken apart.

Again, I have no reason to believe that I didn't fix the problem as it's working everytime, when it wouldn't work at all before the mod. When you're looking at the phone from the back, the GPS antenna location has a letter G engraved into the black cover after the battery cover has been taken off. It's right below the electrical type tape that covers the antenna FYI.
[Nexus S General] Sputnikk23:
*#*#gpsclrx#*#* always fixed my gps woes and i had a lot. no hardware mod required.
[Nexus S General] VOLTAGEROCK:
What does that do by the way.? Because my mod works everytime and you never have to use the code you just put up. Even though I appreciate you putting that there. Also, what type of problems were you having with your navigation? Did it work periodically? Did it never work like mine? Just curious as to the problem you had with your navigation. Thanks

Dan
[Nexus S General] RogerPodacter:
I can confirm this hardware mod fixed voltages gps. He's gone thru 2 nexus s phones and both GPS would constantly lose the position every few minutes then reacquire, and show a huge circle for his position. Somehow this hardware mod fixes some design issue with the nexus s where a shielding isn't properly grounded. And also he extended the GPS antenna with a wire for good measure.

By the way it was the sprint nexus s 4g he modified.
[Nexus S General] jwhistler:
Please post pictures to go with your narrative. I would like to try this!
[Nexus S General] VOLTAGEROCK:
O

Thanks for the clarification nation, Podact.
[Nexus S General] Sputnikk23:
wipe gps data. not the same thing as the gps status wipe (which didn't work for me). try it, doesn't really hurt anything. seems a software code is worth a shot then opening up the phone you know?

Some ROMs it never worked. Other ROMs it was sporadic. When I would get it to work, it always eventually "lost" its ability to lock, etc.

But hey.. if you want to get all hyper-sensitive over your mod.. go for it. Was just throwing another method out there for the faint of heart.
[Nexus S General] VOLTAGEROCK:
I am sensitive as I cried at your remark, and then I got really hyper and started running in circles with joy that my nav works. So I guess you're right, I am hypersensitive! Btw, I was being nothing but nice to your reply. Its OK. I forgive you.
[Nexus S General] VOLTAGEROCK:
Pics requested

Check out the pics. One of them shows some solder on the silver shielding so it makes better contact with the connector when they close back up. The other shows a 30 gauge red wire soldered to the gps pin and running down the phone. Hope this clears up what you guys need to do to get the gps to finally work on this dag gone phone.
[Nexus S General] greg2826:
.I've been using navigation and never had such a problems.my gps always locking under 10sec and doesn't loosing signal.

Btw i live in UK and using nav in big city.
[Nexus S General] VOLTAGEROCK:
Do a search for Nexus S 4g on sprint nav problems and you'll see a whole slew of people with problems.
[Nexus S General] snowmanwithahat:
I guess I got lucky?

I've used navigation a ton of times and never ran into an issue with it. I've had locks faster than the Epic 4g I had before and it's just about been flawless.

What are the issues that you guys have been seeing? If it was hardware related that'd definitely explain why some of us have seen it and some have had no issues at all. Hell, it might even stem all the way back to the Galaxy S GPS issues they had during the first months of release
[Nexus S General] RogerPodacter:
Its a hardware problem design defect due to a shielding which doesn't always make good contact. Some people may not have it if your phone didn't get bumped hard or a number of possible causes. But the shielding barely makes contact and this is the problem. A Google search reveals that TONS of nexus 4g users can't hold a GPS lock, and it constantly loses then reacquires the lock making navigation useless. Great if some people don't have this issue but many users do and I'd posit that many people have jostled their shielding lose from regular wear and tear due to this design defect.

Also the gsm hardware may be slightly different than the CDMA antenna etc.
[Nexus S General] polobunny:
That just reminded me that when I got my Nexus S, back a year and a half ago, brand new in the box from my carrier and everything, I had to tighten a screw. The back cover would clip properly but the gap would be slightly larger on the top right corner, when looking at the back of the phone.

Coincidentially enough, that screw is not too far from the GPS. I tightened it and that was it, but it might be something to check for other people.

Edit: Disregard that, the GPS is on the other side. Unrelated!
[Nexus S General] Bls440:
Oh god, I'd like to fix my NS GPS so much but I'm rather clumsy and scared to mess everything up. Good work though and thanks for the pictures.
[Nexus S General] polobunny:
I'm thinking just making proper contact between the shield part could help a lot with people not getting a fix quickly. You could technically use anything conductive and sandwhich it properly between the cases and the board.

I'm thinking aluminum foil here, easy to bend in a tiny piece and readily available.
[Nexus S General] VOLTAGEROCK:
Very good idea. Of course this is if that shielding is the problem. It probably is. That wire I ran most likely does nothing or maybe it does. Only way to find out would be to remove it and see what happens.
[Nexus S General] VOLTAGEROCK:
Yeah, it would be the top left screw! But anyway you did get lucky because when I do a search on this nav problem, I come up with so many people with the same problem.
[Nexus S General] greg2826:
Aha, didn't know about that. :(
[Nexus S General] dumbdroid:
Maybe on the 4g model....i use my gps daily and it is the best gps from a mobile phone i had ever seen.
[Nexus S General] VOLTAGEROCK:
I don't understand what you mean. Are you saying that the Nexus S came in a non 4 G model?
[Nexus S General] dumbdroid:
Yes.
[Nexus S General] CrackerTeg:
OP, I have a couple of questions for you. In the pic showing the shielding, it doesn't look like that would make contact with anything except for the top of those two connectors that are directly above the connection you soldered the wire to. Also, the wire you used, was it shielded? My GPS worked beautifully before but lately, its just not doing it anymore. Probably because I've dropped it a few times but each time it was with a case.

As for your trip between Jersey and RI, I did a similar trip from New London to Jersey the other day and that's when I realized my GPS was crap when a couple of months ago, from Miami to New London, flawless operation. Only difference between the two trips was the OS. ICS - JB.
[Nexus S General] VOLTAGEROCK:
OK, firstly, when you close the cover back up, the solder that I put on the shielding makes contact with the harness that has a completely metal and negative (grounded) surface. This is where that shielding strip that i applied solder to touches. The solder does not touch the connection where I put the red wire. Make sure you do not ground that!!

The wire is 30 gauge with a red housing over it. I doubt it shields anything! I put it there just for redundancy purposes, I guess just to help as I didn't know if the antenna was good or bad.

Hope this clears up your issue!

Dan
[Nexus S General] VOLTAGEROCK:
Remember, the theory here is that the shielding is not getting grounded properly. You would be able to tell if you opened your phone up and see how poorly the shielding was positioned and could easily through bumps and shaking lose its solid connection that the phone came with when new.

I'm just telling you what worked for me and what I hope works for everyone else including you!
[Nexus S General] CrackerTeg:
I meant jacketed not shielded. Sorry about that. I'm an ET for Christ sake and jumbled the terminology.

Anyway, I went and did it anyway prior to your response and had no GPS connection. As for the solder you added on that back case, there is no part like that in the back case of the 9020a so that part cannot be done. I desoldered the added wire on that left spring as it seemed to kill my GPS so I'm back to square one. I did, however, open the spring up a bit to attempt a stronger connection to the built in antenna. I'm going to test what I did and see if that improved my GPS issues.
[Nexus S General] VOLTAGEROCK:
You didn't see the silver paper type sticky cover on the inside of your cover? The one I soldered to? Do you have the sim card (GSM) model? I have cdma with sprint.

Obviously as we're in that forum!!

Made that mistake as we're in the general Nexus S forum.

PM me as I wanna talk more about this on phone. I can't keep typing as I'm at work. And then w my girl after work n she hates electronics!
[Nexus S General] CrackerTeg:
Pm sent.
[Nexus S General] asemore:
I also have but GPS reception.

I have the GSM version.

Here is a pic of the cover. Totally different.

Don't know if the two metal plates ther are used for the GPS.
[Nexus S General] VOLTAGEROCK:
OK, first of all, you are looking at the way wrong part! That's the inside of the battery cover and those two gold contacts are for NFC (Near Field Communication). You need to go a step further and open the device. There should be 6 screws when looking at the battery side of the phone. One in each corner and and two in the middle outside. Look at my pics and read my thread. It explains this a lot more. I need to see the inside of the phone cover of your GSM model to see what the difference is with the CDMA version to see where your options are as far as getting the GPS to work.

It's really easy to open up. Just do a search and you will find plenty of help.
[Nexus S General] CrackerTeg:
I apologize for not getting back to you man. Finding a cam isn't easy for me. I'll see what I can do here shortly since I'm still at work and bored.
[Nexus S General] VOLTAGEROCK:
No big deal man. I completely understand what it's like to try to get some pics up here, especially when most of the time, the only camera we own is built into the phone we are trying to take a picture of! But for all the GSM models, I have to see the inside, as there has to be a shielding issue. I saw that you tried the wire and then de-soldered it, so that looks like that is not the cause of this problem. I hope you find a shielding strip like the CDMA version and can get a better contact to the ground like I did.

I'm telling you, and rogerpodacter on this site can attest, I went from having useless Navigation to now having something I am so happy to use on a daily basis. I wish there were more CDMA people out there and can try this mod to see if it helps all the Nexus S GPS problems! I want to be a savior!