Database Users

Charge from USB?

This may seem like a really stupid question, but has anyone tried/succeeded in seeing if this device can charge off USB? That is really the only thing I dislike about it now that I have Dexter, I travel a lot and hauling an extra charger is just a pain.

What about charging thru the docking port if we had a usb cable to fit it?

im sure docking port would work, as it does work with folio100 as example.
but usb charge, is probably a no-go, i guess hardware needs to be redesigned to enable usb charging although kernel does allow you to enable it, but again, maybe a pin of the chip needs to attach to another location on board to enable it.
on folio100 it did not work.. and without kernel source to try changing/enabling it we dont know if it would work..
and remember the port is host/device based, so it might also be it only works when in device mode, which also means travellers would not be able to attach anything if they charge it.. so might be conflicting interests on how it should work. (if it worked)

Thanks for the reply.
I know I've seen this question asked elsewhere, but not for a while. You mentioned the docking port, have we seen ANYTHING that connects to it? even if not a full docking station, a cable to connect via USB to a computer.
Or has anyone figured out a pin map that someone could cobble together a cable

D.i.y usb otg adapter/cable

Hi,
I made my own usb otg adapter from a plain usb a to micro b adapter. You have to connect pin 4 /which is not connected/ to ground to fire up host mode.
Edit: It is not easy to dismantle a usb connector or adapter and it requires soldering. So I guess anybody with the necessary skills will find the pin on his own. I will not post photos because my solution is far from being pretty.
For everybody else: the nokia USB OTG cable is wired the same way so it is very likely that it will work. (on Hungarian forums I saw references that it works, but I can not guaratee it.)
Tommorow I will go buy one and report.
USB Host mode will allow to connect USB pendrive, mouse, keyboard etc. to the SGS II.
Sent from my GT-I9100 using XDA App

richyy74 said:
Hi,
I made my own usb otg adapter from a plain usb a to micro b adapter. You have to connect pin 4 /which is not connected/ to ground to fire up host mode.
Sent from my GT-I9100 using XDA App
Click to expand...
Click to collapse
this is very useful for people like me who knows how to solder things, but for the people who have absolutly no Idea what you are talking about, you should add more details/pictures to the OP so the people who doesen't know much about electronics know what you are talking about, and what benefits it brings for them.
I myself will probably make one or more, so I don't have to always take my USB OTG with me all the time.

kaukassus said:
this is very useful for people like me who knows how to solder things, but for the people who have absolutly no Idea what you are talking about, you should add more details/pictures to the OP so the people who doesen't know much about electronics know what you are talking about, and what benefits it brings for them.
I myself will probably make one or more, so I don't have to always take my USB OTG with me all the time.
Click to expand...
Click to collapse
May be you dint know about this thread
http://forum.xda-developers.com/showthread.php?t=1092493
This was explained with pics a long time ago

Yeah sorry. I never saw that. Thanks.

richyy74 said:
Yeah sorry. I never saw that. Thanks.
Click to expand...
Click to collapse
Why be sorry. This forum is to help each other out.

OTG Cable USB (B) to Micro USB (A) Powered with AAA batteries
As one knows, Samsung has promised a HMI Cable
You noticed it is not only a cable but a box out of which you may plug in an extra power supply.
The obvious reason is if the passive monitor does not furnish 5V, the phone will rapidly be out of power.
Now you know that to obtain video rather than anything less, Pin 4 (sense) and 5 (Ground) of micro USB (male A) must be connected with a 365K resistance.
I suppose the dock Samsung is selling for I9100 (yes, I have it) is grounded at 1000K as it provides audio with remote, and yes, the dock provides power supply via extra micro USB as well.
I come to my point: If I want to access any USB data On the Go, I need a cable OTG with 2 ports: USB 2.0/3.0 (female, B sided) to a micro USB (male, A sided, grounded but with no resistance = 0K). Many of them exist on the market out there.
But it is quite impossible to use because of lack of power supply in the passive device (let’s say a handy 1T HDD usually powered via Host connexion !
Would it be possible to insert some sort of receptacle for AAA battery in the middle of such a cable to provide for power while you are for a long time out of access to an electric plug ? Does such a cable exist somewhere to buy ? What would be the sheme to mount this ? HELP !

Instead of shorting pin 4 and 5 from within the cable head, would it also be viable to short them from within the device itself? Say if I disassembled the phone to access the back of the female usb micro connector and soldered the pins. Would there be any damage caused if the permanently shorted pins 4 and 5 (within the device) is connected to a charging adapter/PC?

[Q] Homemade USB hub? (no soldering!)

I posted this on Plopper's thread here(http://forum.xda-developers.com/showthread.php?t=923864) but thought it might be better here as I might get a quicker reply
"I have bought a 4 way USB hub which has a usb socket on its input lead. This can be plugged into your PC or into a usb mains charger or usb car charger.
If the input lead is plugged into one of the four output sockets and the lead is cut open and the red and black wires are exposed, a 2A 5v charger can be connected to these wires by twisting together and taping.
This then powers both sides of the hub with 2A supply and by-passes the protection.
It does sacrifice 1 output socket but HD2 +keyboard+mouse= happy Ubuntu
Will this work?"
I am dying to try it but thought I'd check with tech savvy types first.
Edit; I am thinking now that the green and white data cables in the input leads may have to be cut and the ends taped, but it may not matter(?)

Have attached photo of the hub and the charger
The charger is an old Nokia one and has a lump of plastic near the end which I assume houses a fuse of sorts.
Reading through Plopper's thread again I am sure this is OK, but am unwilling to brick my HD2!
You could get a 7 way usb hub and add things like external HDD or (my favourite) a usb fan to cool down your HD2!

Working
OK over 300 views of this thread and no reply!
this usually means the idea is a dud or its been done before!
I have searched around but can only find y-cables, which supply extra 500mA from another USB socket but only allow 1 device connection.
If this has been done before, I apologise.
However, I got bored of waiting and went ahead with cutting up leads and splicing wires. I flashed WM6.5 and loaded Ubuntu 0.3 (only one with USB host that I can find!)
AND IT WORKS!!!!!
I had to buy a micro USB cable because I didn't want to cut my stock one (get a data cable because a charging cable only has 2 wires in it).
Note on cable colours, apparently there may be variation on some manufacturer's cable core colours, take care to identify by tracing circuits on the hub and checking continuity from the pins to each core.
Also, being an electrician, I am wondering what the current carrying capacity of the tiny core cables are, I will have to look it up at some point (adiabatic equation) meanwhile check for overheating.
Enjoy! (something to do on wet weekend!)

Homemade USB
i made this, unfortunately i can't use it with 0.3 bucouse i installed magldr and i use Android, and linit tutorial doesn't work for me
http://i54.tinypic.com/2dquiwo.jpg
http://i54.tinypic.com/2zsxz6b.jpg

Impressive!
It sure beats the above from me.
What do you use it with?
What else might support USB hosting?
I prefer to use WP7 and Android too (see sig)

i made it for HD2 for use it with Ubuntu, i hope that the v0.4 come out soon and with usb host support...

Doh!
467 views after first posting this and after re-reading plopper's thread again I have realised what plopper and Mister B were saying in their last posts.
There is no protection in unpowered usb hubs, so no need to bypass it!
I have over-complicated everything.
It is only necessary to change the hub lead plug to a microUSB one and then connect the charger to the usb plug which you have just cut off, then plug it into one of the spare ports.
Oh well never mind!

i take a photo with HD2 on it http://i53.tinypic.com/34dr96v.jpg

很好很强大！

nice... ...but, don't smoke so much....

Guys,
For those using Android, you can try Dorimanx's latest 2.9.9 ROM which claims to have USB Host enabled. I don't have a USB OTG cable to try it on, but let us know if having a self-powered USB hub works on it. Thanks

nikola360 said:
i take a photo with HD2 on it i53.tinypic.com/34dr96v.jpg
Click to expand...
Click to collapse
OMG this thing is amazing! I really want to make something like this, got any pointers on how to do it?

wow thats the crazyest mod ever you should move to hardware moding scection! maby you will get more help!

bever86 said:
OMG this thing is amazing! I really want to make something like this, got any pointers on how to do it?
Click to expand...
Click to collapse
Thanks!....unfortunately i haven't a tutorial, i made it only with my fantasy, i saw 2 DVD cases and i made it.
Guys,
For those using Android, you can try Dorimanx's latest 2.9.9 ROM which claims to have USB Host enabled. I don't have a USB OTG cable to try it on, but let us know if having a self-powered USB hub works on it. Thanks
Click to expand...
Click to collapse
i tried it (XB V.19 that is based on it, with the same kernel USBH enabled) but unfortunately it doesn't work, i saw in the system partition of this rom and i saw that there aren't any driver for USB hardwares support (USB Keyboard, mouse, USB Flash memory...)...so i think that the problem is this (no drivers support)

nikola360 said:
i take a photo with HD2 on it http://i53.tinypic.com/34dr96v.jpg
Click to expand...
Click to collapse
This looks really cool, you should produce it and offer it, I guess I would buy it

diy mircousb hub

hi folks,
i would to like to build a micro usb hub.
e.g. 1 male connector and 2 female connector.
does anybody have experience in micro usb to stabilize the voltage and current?
thanx

KindsKoPP said:
hi folks,
i would to like to build a micro usb hub.
e.g. 1 male connector and 2 female connector.
does anybody have experience in micro usb to stabilize the voltage and current?
thanx
Click to expand...
Click to collapse
That would be interesting to see, I think your gonna need drivers for that as well because your gonna need a switch to cycle back and forth on what connector your using, and thats gonna be hard to do from scratch. I was contemplating doing something similar to that but wound up at a dead end. If you figure it out let me know.

it won´t need a driver. i want to build as a host hub. but the current is too low i think, so it is difficult to stabilizise the current,,
mbm262 said:
That would be interesting to see, I think your gonna need drivers for that as well because your gonna need a switch to cycle back and forth on what connector your using, and thats gonna be hard to do from scratch. I was contemplating doing something similar to that but wound up at a dead end. If you figure it out let me know.
Click to expand...
Click to collapse

It's not a question of stabilizing the current.
It's supposed to be 5 volts throughout the USB spec.
If you are using a cell phone as the host, that already produces regulated 5 volts through a charge pump.
The amount of current out of a cell phone is maybe around 100 mA.
That's what you have to work with.
If it's not sufficient for what you want then you need an external power source, not a regulator.
Hubs can be power hogs.
The spec says that a hub can take up to 100 mA all by itself.
To make a micro USB you can either take an existing hub and change the connectors.
Of course since the PCB pattern will not match up you'd have to wire the connectors in discreetly.
If you really wanted to make a real job out of this, buy a hub IC for $3,
lay out a PCB, slap on a 24 MHz crystal and connectors.

???
the idea is to build an mobile hub for tablets or smartphones for plugin external devices like sd card reader or usb stick and
mouse and keybord. hub will stick in a phone and plug in the external devices. i already had tried with a keyboard and mouse with standard usb and it works. i had already build some devices with micro usb connector. so i would like to use all devices at the same time and outdoor. i try to solve the idea without a lot of adapter..
if the usb give all devices 5v and 100mA at the same time, that would be great, without an additional IC power supplier..
thats all

i found out thats not possible to use more than 2 gadgets at the same time cause of the voltage without an external power supplier. keyboard and mice work at the same time but i f u want to plug in a 3rd gadget then wont work. 1 solution could be a mobile battery with 5v connecting with the hub. or make a built in battery in the hub..
@ renate. maybe u have an suggestion?

I have a jig for measuring current consumed by USB peripherals: http://forum.xda-developers.com/showpost.php?p=30668417&postcount=26
I use USB with only low power things like a keyboard or else
with a powered hub (also back-powering the Android).
The second option is more like a docking station.

KindsKoPP said:
hi folks,
i would to like to build a micro usb hub.
e.g. 1 male connector and 2 female connector.
does anybody have experience in micro usb to stabilize the voltage and current?
thanx
Click to expand...
Click to collapse
The 2 female connectors don't make much sense i think, because:
I can't think of any device you would like to connect with your phone as host that has a µusb connector..? You would need 2 additional OTG-cables in almost all cases
You would need OTG capability for security reasons: Imagine you hub is pluggend in you phone and you connect you computer to the hub too -> Data crash + 2 power sources in parallel -> risk of damage
I would use a normal tiny usb hub and only change the cable

u did not read my post above attentively or?
quote:
i had already build some devices with micro usb connector. so i would like to use all devices at the same time and outdoor. i try to solve the idea without a lot of adapter..
and the gadget are already automatically OTG. I already thought all about that before!
-schumi- said:
The 2 female connectors don't make much sense i think, because:
I can't think of any device you would like to connect with your phone as host that has a µusb connector..? You would need 2 additional OTG-cables in almost all cases
You would need OTG capability for security reasons: Imagine you hub is pluggend in you phone and you connect you computer to the hub too -> Data crash + 2 power sources in parallel -> risk of damage
I would use a normal tiny usb hub and only change the cable
Click to expand...
Click to collapse

[Q] USB OTG through SlimPort HDMI power

Is it possible to take the SlimPort voltage and redirect it to USB to supply USB OTG?
Sorry if the question has asked before.

There is an entire thread dedicated to getting OTG working. Try asking there.

estallings15 said:
There is an entire thread dedicated to getting OTG working. Try asking there.
Click to expand...
Click to collapse
Here is the dev thread where shaky provided an experimental kernel, and some discussion is going on, but you need ten posts to post there:
http://forum.xda-developers.com/showthread.php?t=2048545&page=13
Here is 37 pages of complaining :
http://forum.xda-developers.com/showthread.php?t=1966864
WildCivil said:
Is it possible to take the SlimPort voltage and redirect it to USB to supply USB OTG?
Click to expand...
Click to collapse
AFAIK, HDMI (which slimport provides) only guarantees 55 mA. Regular USB on a PC provides 100 or 500 mA, USB OTG only needs to provide 8 mA, but I think many phones supply more. I think it could work, but probably not with all devices.
However the first step before trying to supply Vcc voltage is to get USB working with an external power supply. Some people have tried this, currently without success. Once that works, one can try to poke around in the kernel and get the Vcc power to turn on. There are a couple of switches to try, and it doesn't neccessarily have to come from the Slimport.
One word about why it doesn't work now: I think Google/LG disabled it because it was either not 100% compliant with the USB specs, or there were some problems with the simulaneous use of slimport and USB. Since the slimport feature has higher priority, if both are incompatible, USB OTG is thrown out. And if a feature only works partially, it's better for the vendor to just cut the support altogether than to get a lot of support requests.
That being said, it would probably work fine for 'us hackers' who are willing to risk that some peripherials work and some randomly don't, and are willing to use a Y cable if neccessary.