Develop Bugs

[Q] USB OTG *AND* charging at the same time.

Hello,
Can you have USB OTG and phone charging at the same time? Or even better: HDMI + USB OTG + charging? Without power the phone discharges fast, not to mention - with HDMI out connected I won't be able to connect external HD with movies... Oh, bother...
Or is there some magic do-it-all dongle?

I need it too .
I hate some cable in my bag. One Cable for all is great

USB OTG does not support charging as it has to supply current to the external device.
MHL (HDMI output) does.

Dude, I really hope I'm not misunderstanding, but what is the problem to which 'USB OTG and charging at the same time' is the solution?
Surely you pop your USB stick in, transfer the file and then... stick the charger/HDMI cable back in... and stream wirelessly/over your network?
What were you hoping to achieve? There are several options...

Just taking a guess... maybe he wants to use keyboard and mouse etc with his phone, desktop style
Sent from my GT-I9100 using XDA App

Or maybe I just want to play anything from my 1TB HD WITHOUT deciding what should I copy to my phone (which is a waste of time...)

ssuukk said:
Or maybe I just want to play anything from my 1TB HD WITHOUT deciding what should I copy to my phone (which is a waste of time...)
Click to expand...
Click to collapse
I wanted to do the same thing but it isn't possible . I do however stream from my nas if I don't want to copy stuff to the phone.

Technically, the USB-OTG standard includes provisions for handling this.
There are several occasions where you would want to plug an accessory into a USB-OTG port and still be able to hold the state-of-charge in the host device.
The specific document: Battery Charging Specification, rev 1.2
ACA subsection (Accessory Charger Adapter)
The ID_OTG pin acts as an input in this mode of operating, indicating whether or not the host is allowed to charge.
Figure 6-6 shows the typical architecture.

Sounds promising. I will look into that! Thanx.

Any news on this?? :fingers-crossed:

so can we use otg and mhl at the same time without charging

Yes, this is pretty much possible. I have implemented the aforementioned OTG ACA support and got it to CyanogenMod9 upstream. Anything which uses the same kernel (or, if you can cherry-pick changes and compile your own kernels), could use that too. Changeset URL: _ttp://review.cyanogenmod.com/#/c/15850/
You need to use a regular USB OTG cable, but place a 36 KOhm resistor between ID pin and GND, then you should connect GND and Vdd to some power source. I used an MHL adapter which I had no use for, as it had two of three connectors I needed. This setup allows me to watch movies from 2.5" notebook hard drive while simultaneously charging my phone if I plug in a 2A-rated adapter. Note that it's impossible to use 650mA charging rate due to chip restrictions (USB HC is too stupid to understand the direction of current flow, and it reports an over-current condition); you have to settle on 450mA.
If you don't know how to solder, or if you use something else than CyanogenMod9 and cannot compile your own kernels, you are out of luck.
I have tried to find an existing USB OTG ACA dongle, but I was not able to find any. If you will be more lucky than me, you can just use it--my patch is compliant with USB specification and will support any compatible dongle.

It's possible.
You need cable y usb. I did it myself.
http://a2.sphotos.ak.fbcdn.net/hphotos-ak-snc6/s720x720/206110_371488136240210_1887794367_n.jpg
watch icon battery

What parts do I need?
wojtaz131 said:
It's possible.
You need cable y usb. I did it myself.
http://a2.sphotos.ak.fbcdn.net/hphotos-ak-snc6/s720x720/206110_371488136240210_1887794367_n.jpg
watch icon battery
Click to expand...
Click to collapse
What specific parts did you use for your OTG / Power Y
The ability to charge my device while playing video off a usb flashdrive is my goal for this.

ZedZardoz said:
What specific parts did you use for your OTG / Power Y
The ability to charge my device while playing video off a usb flashdrive is my goal for this.
Click to expand...
Click to collapse
A few wires. See my post above for the details.

whitequark said:
Yes, this is pretty much possible. I have implemented the aforementioned OTG ACA support and got it to CyanogenMod9 upstream. Anything which uses the same kernel (or, if you can cherry-pick changes and compile your own kernels), could use that too. Changeset URL: _ttp://review.cyanogenmod.com/#/c/15850/
You need to use a regular USB OTG cable, but place a 36 KOhm resistor between ID pin and GND, then you should connect GND and Vdd to some power source. I used an MHL adapter which I had no use for, as it had two of three connectors I needed. This setup allows me to watch movies from 2.5" notebook hard drive while simultaneously charging my phone if I plug in a 2A-rated adapter. Note that it's impossible to use 650mA charging rate due to chip restrictions (USB HC is too stupid to understand the direction of current flow, and it reports an over-current condition); you have to settle on 450mA.
If you don't know how to solder, or if you use something else than CyanogenMod9 and cannot compile your own kernels, you are out of luck.
I have tried to find an existing USB OTG ACA dongle, but I was not able to find any. If you will be more lucky than me, you can just use it--my patch is compliant with USB specification and will support any compatible dongle.
Click to expand...
Click to collapse
Duh, I read right past this post... 36KOhm on ID <<< got it, now to experiment!

wow!
it would be amazing if such a device existed!

Hello,
I'm new to this forum as i didn't need it yet but now I have a question.
I know this thread is kind of old and I'm not sure if there are still (m)any people using a GT-I9100... though it would be interesting if anyone found a solution on this topic.
I read several threads where people were discussion if charging and OTG is possible at the same time but no one could verify a specific resistor. Actually i tried a resistor valued 124k between GND and ID but it didn't work. I also read about 36k and other values but nothing verified. Could take a while to try several resistors but i really no one knows a solution i'd try this
So just so sum up, i don't need "MHL and charging" or "audio out and charging". The mode i'm looking for is "OTG and charging".
My Goal: a Docking Station with mouse, keyboard, flash drive(s) and charging to remote control my computer with a software like splashtop.
Hopefully anyone has useful information on this, thanks a lot for any kind of support

burnsn said:
So just so sum up, i don't need "MHL and charging" or "audio out and charging". The mode i'm looking for is "OTG and charging".
Click to expand...
Click to collapse
You need a kernel patch to make it work. See http://forum.xda-developers.com/showpost.php?p=30141914&postcount=12

whitequark said:
You need a kernel patch to make it work. See http://forum.xda-developers.com/showpost.php?p=30141914&postcount=12
Click to expand...
Click to collapse
Thanks for your answer!
Today i made my 36k cable, this weekend i should have some time for the kernel patch - hopefully
I still have some questions about the kernel as i didn't use any custom ROMs etc on my phone. All I have is a "standard" root kernel without any further changes but root. Need some hours to read into this. What i didn't understand: Do I have to use a specific CM9 or can i use any CM9 (or maybe CM10 or any other CM past 9)?
I wasn't able to get the link working "_ttp://review.cyanogenmod.com/#/c/15850/" when replacing "_" with "h". What can I find on that page?

[Q] USB host? Is it possible with the a100?

Hello friends, I am new to this forum, but certainly not new to the tablet world. I purchased the iconia a100 a few weeks ago and I must say it is a superb tablet in almost everyway. That being said, I am trying to come up with a solution for the lacking usb host on this tablet. I am certainly not a dev, but I am wondering if there is anything in the works for a working usb host? Does anyone know if acer has any plans to offer an adapter or even a different docking station with the usb host working from the 40 pin? If anyone has any ideas or would like to start a project i will be glad to help in anyway I can. While i was researching this usb host problem i see that there was a very sinilar situation with the galaxy which has since been resolved. Any suggestions? Thanks

Not yet possible, but you can pretty much count on it to be baked into a custom ROM when we get the ability to fully unlock and root this device. Root is already possible, and done. Unfortunately, we cant really do much development on it right now due to the encrypted bootloader. Most devs are waiting for the ics update in January to get the ball rolling on tweaks and hacks to the a100.
Sit tight, they'll have you up and running in no time
ummmmm............ could you repeat that?

This is also #1 on my wishlist. However, I don't know if that is even possible with a custom ROM; it requires the hardware to support it and I don't recall seeing any teardown that states that it would be possible.

I've seen it done in various phones, but don't know if its been posted on any here, but I'm sure a search on the forum would help find them. Its a matter of reconfiguring the port in the programming and getting an adapter from micro USB to standard USB.
But don't quote me on any of this, I could be mistaken with other devices. There has been talk about USB hosting on the a100 before.
ummmmm............ could you repeat that?

Yes, you would need something called an OTG (on the go) adapter. The hardware in the device has to support host, so it is not JUST software.

I can confirm that i have tried the otg adapter as well as other adapters...and it only works as slave. I would just like someone to confirm that usb host is possible [that the harware supports host capabilities]. I am just glad to see there are more people interested in fixing this problem as this tablet is superfast and top quality in every other way in my opinion. Thanks again

Maybe something comes out of
http://www.circuitsathome.com/mcu/programming/android_adk_compatible_usb_host_library_release

I ordered an OTG cable and once it comes I will take a look at enabling USB host mode.
I am guessing that the hardware supports USB host, but will need a kernel module and some scripts to enable it.
I also suspect that the USB port will not supply power to an attached device. If this is the case, the workaround is to attach a powered USB hub to the OTG cable.
Crossing my fingers, and waiting for that OTG cable to come in the mail...

flar2 said:
I ordered an OTG cable and once it comes I will take a look at enabling USB host mode.
I am guessing that the hardware supports USB host, but will need a kernel module and some scripts to enable it.
I also suspect that the USB port will not supply power to an attached device. If this is the case, the workaround is to attach a powered USB hub to the OTG cable.
Crossing my fingers, and waiting for that OTG cable to come in the mail...
Click to expand...
Click to collapse
USB host is enabled in the kernel. Hardware does support USB host.
Acer left it off the board entirely, so I doubt much can be done without hardware modding, which I'm all for lol.
Tapatalked from my Galaxy S II.

Sounds grim if the hardware connection is not there, are we sure that the port is just not supplying power?
do the kernel modules load? (e.g. usb-hid, usb-storage)
Has anyone actually tried to:
a) insmod the correct modules
b) force change to host mode (the device probably has to be either slave or host, not both at once)
c) connect something (e.g. a mouse or a thumbdrive) through the otg cable and a powered usb hub?
At least I won't have to build a kernel to test this out.

flar2 said:
Sounds grim if the hardware connection is not there, are we sure that the port is just not supplying power?
do the kernel modules load? (e.g. usb-hid, usb-storage)
Has anyone actually tried to:
a) insmod the correct modules
b) force change to host mode (the device probably has to be either slave or host, not both at once)
c) connect something (e.g. a mouse or a thumbdrive) through the otg cable and a powered usb hub?
At least I won't have to build a kernel to test this out.
Click to expand...
Click to collapse
I know this comes up every now and then, I really dont know how far anyone gets before giving up. Feel free to try out whatever you want, while I don't care about USB host I know a lot of people do and would love an update on any progress anyone can make. Even if its just things that don't work.
Acer is generally lazy and cheap, we use the same kernel source as the a500 which has host, which is why we also have it. It could be modules, though I doubt its so simple. Also a powered hub would be needed, there is no power supplied to the port that anyone has found. This could be remedied with some hardware work I'm sure. The hub would also need to be one way, meaning not dumping power to host as I doubt the a100 will take it and without protection would likely suffer damage if the power pins are even hooked up.
The system itself runs at 12v though I'm sure there's a 5v rail someplace but if it can support powering anything past maybe a flash drive is unknown.
Take a visit to iconia-dev on free node, they'll know more of this then probably anyone here does lol
Tapatalked from my Galaxy S II.

The A500 does not implement USB otg, but rather a standard USB port. In other words, USB otg is not necessary for the A500 since it has a standard port. The USB otg standard allows a the port to act as both master and slave depending on the connection. In the A100 service manual, the schematic shows only one connection to the chipset (client), host is unconnected, which could be a problem. However, it is known that the Tegra 2 can support otg connections. I'm not certain, but it may be possible that by shorting pins 4 and 5 in the micro usb connector (ie, using an otg cable) and with the proper kernel level support, the A100 could still act as a USB host, albeit with no power supply to the micro USB port.
I'll continue to investigate this once I have a chance to build otg support into the kernel and recieve the otg cable.

flar2 said:
The A500 does not implement USB otg, but rather a standard USB port. In other words, USB otg is not necessary for the A500 since it has a standard port. The USB otg standard allows a the port to act as both master and slave depending on the connection. In the A100 service manual, the schematic shows only one connection to the chipset (client), host is unconnected, which could be a problem. However, it is known that the Tegra 2 can support otg connections. I'm not certain, but it may be possible that by shorting pins 4 and 5 in the micro usb connector (ie, using an otg cable) and with the proper kernel level support, the A100 could still act as a USB host, albeit with no power supply to the micro USB port.
I'll continue to investigate this once I have a chance to build otg support into the kernel and recieve the otg cable.
Click to expand...
Click to collapse
Thanks for that, but one thing, its already in the kernel. However Linux society and/or waydownsouth would know more about what's in there, I just know it isn't blocked there. Modules etc I don't know. I look forward to seeing some progress on this topic.
Tapatalked from my Galaxy S II.

Pulled the kernel config from my tablet, you are correct, otg support is built into the kernel.
I'm using ezterry's kernel, almost everything is built in, there are only a few modules that have nothing to do with this.

I tested with an OTG cable, which shorts pins 4 and 5 in the micro usb connector. As expected, this did not enable USB host mode.
I tested wtih 5V going into the micro usb connection, as some of the non-powered devices need that voltage applied to activate the port, still nothing. (and no damage!)
I added a few other things to the kernel, the dmesg output changed slightly compared ezterry kernel
When connecting otg cable with 5V, dmesg shows:
tegra-otg tegra-otg: SUSPEND --> PERHIPHERAL
vbus connected, lock wakelock
tegra-otg tegra-otg: PERHIPHERAL --> SUSPEND
tegra_usb_phy_power_off(inst:0), phy->regulator_on: 1, line : 2754
tegra_usb_phy_power_off(inst:0), tegra_get_revision(): 0
vbus disconnected, unlock wakelock
android_work: did not send uevent (0 0 (null))

In the possibility that USB host is not possible on the micro usb port, a hardware mod could be done. There are points for a mini PCI-E connector on the motherboard (this is where the 3G module would be for A101). Solder wires to pins 36 and 38 for USB data, 4 for ground and connect them to a usb port. The PCI-E only gives 3.3V, but power could be supplied by a powered hub instead. There is even space inside the unit to mount a micro usb connector on the end with the power button.
The main roadblock is that the solder points are on the back side of the pcboard so you have to fully disassemble the unit to remove the motherboard. It would actually be fairly easy to do if the points were showing when you remove the back cover.
I don't think I have the nerve to actually try this.

flar2 said:
In the possibility that USB host is not possible on the micro usb port, a hardware mod could be done. There are points for a mini PCI-E connector on the motherboard (this is where the 3G module would be for A101). Solder wires to pins 36 and 38 for USB data, 4 for ground and connect them to a usb port. The PCI-E only gives 3.3V, but power could be supplied by a powered hub instead. There is even space inside the unit to mount a micro usb connector on the end with the power button.
The main roadblock is that the solder points are on the back side of the pcboard so you have to fully disassemble the unit to remove the motherboard. It would actually be fairly easy to do if the points were showing when you remove the back cover.
I don't think I have the nerve to actually try this.
Click to expand...
Click to collapse
Well if you want to play it like that, you can use a mini pci-e > usb adapter, which is also available with and without sata too lol. It would, maybe, depending on the board used, even line up with the sim slot, so minimal case cutting would be needed to make it accessible for usb. Straight drop in for an A101, though we lack the actual slot for it. Might be something I'll try later on.
Edit: I forget, does the sim slot line up with the pci-e slot? Been awhile since I saw the inside of one, so I may be wrong on that point.

There isn't an actual mini pci-e connector in my tab, it's just the solder points, so you would have to solder on a connector to use the adapter. The sim slot doesn't line up. But it looks like the empty sim slot is not high enough for a micro usb port to fit anyway.

I tried the hardware mod. Unfortunately the mini pci-e is not hooked up to the system. In other news, the motherboard is very easy to remove and reinstall.

there is a ROM in which they have implemented the usb otg?
Inviato dal mio Galaxy Nexus con Tapatalk 2

USB OTG + Charge?

I just recently got a Samsung Galaxy Note 10.1 and so far I'm quite happy with it --- except one thing, I cant find a cable that lets me charge the tablet *and* use the USB Host (OTG) port... (i.e. read files off a USB drive or play a game with a USB game pad while keeping the tablet plugged in)
Is there a way to do this? it would seem to me that all it needs is a splice to give power to the Power +/- pins on the connector while keeping the OTG Data +/- pins active...? (I know nothing about the pinout so I could be wrong on this)
Just to be clear I want to use the OTG adapter WHILE CHARGING (I've found one device that gives both these options but says "only one function may be used at a time")
Ideas?

Discussed dozen times in 10.1 forum. Actually it is not possible. Build an otg + power cable myself but it only works with timing and with a specific procedure... quite annoying. Wait for a custom rom somewhere in the future as I do.

You may have issues trying this, OTG cables are iffy under Jelly Bean. Some may work, some may not. In fact, Google removed references to OTG support for Nexus devices last November since OTG is so spotty. Splicing a cable that might work may kill it. Decent battery-powered USB and SD hubs are available and bypass the OTG problems. I have the RavPower RP WD01 and love it. The USB port will support drives upto 3T. It also has an SD card slot.

mke1973 said:
You may have issues trying this, OTG cables are iffy under Jelly Bean. Some may work, some may not. In fact, Google removed references to OTG support for Nexus devices last November since OTG is so spotty. Splicing a cable that might work may kill it. Decent battery-powered USB and SD hubs are available and bypass the OTG problems. I have the RavPower RP WD01 and love it. The USB port will support drives upto 3T. It also has an SD card slot.
Click to expand...
Click to collapse
Powering the USB devices isn't a problem, I have a nice hub that powers them without issue, even extremely power-hungry devices. I was wanting to charge the tablet's battery while using the OTG adapter (original thought was for USB-gamepad-ing since high-requirement games drain battery, but I've since started using a PS3 controller over bluetooth so I can use the OEM charge cable and wireless for gaming --- but USB drives I'd have to copy the files over to internal flash or a MicroSD card to view while charging and i've found that the cards dont like files that are 8gb in size... (FAT-32 restriction iirc))
47kt said:
Discussed dozen times in 10.1 forum. Actually it is not possible. Build an otg + power cable myself but it only works with timing and with a specific procedure... quite annoying. Wait for a custom rom somewhere in the future as I do.
Click to expand...
Click to collapse
I saw that when I google'd but thought maybe there had been some new developments (especially with how this site's members love to tinker with electronics and write custom firmware). It's not a huge issue, since the Note 10.1 has amazing battery life (it's actually matching or doing BETTER than my iPad in most circumstances) I just like to never run the battery down low.. (why cant tablets have user-replaceable/swapable batters like most phones?!)
Thanks for the info!

[Q] Has anyone managed to get USB OTG + Charging working (preferably in software!)

I've searched and found various posts from a long time back that seem to imply it's possible but haven't been able to find anyone saying they've actually done it.
I want to be able to use an OTG cable with a usb y cable, to allow me to plug in a usb device and charger at the same time. Note I want to charge the phone itself, I am not trying to supply power to the usb device.
International HOX running CM11 latest monthly, in case it's relevant.
(I'm retiring my HOX and thinking about using it as a mini server - I want to plug in ethernet by USB adaptor to provide the network and charger to keep the phone running 24/7 )

[Q] moto-G Y-cable for recharging (first branch) and data transfer (second branch)

Hi,
I realize that this forum is a better match for a question that I posted earlier in a more general forum: http://forum.xda-developers.com/android/help/moto-g-y-cable-recharging-branch-data-t3148505. Alas, I received no replies in the former forum and I thus hope that there is a better chance that someone is able to shed more light on this in this forum.
The question goes like this:
I have a device with micro USB port and I wish to have this device
connected to a moto G (usb OTG) at all times so that I can use the
phone to relay data from the device to the Internet without any kind
of interruptions.
This works fine with a combined OTG cable with a micro-USB connection
(e.g. http://www.ttvjaudio.com/Nightscout_TTVJ_Micro_USB_to_Micro_USB_Cable_p/ttvj000001.htm) or with a micro-USB to USB male cable (from device to otg cable)
combined with a USB OTG cable (from usb male to the moto G).
Alas, the phone need to be recharged (and the phone will charge the device)
and I was hoping that there existed some kind of Y-cable (one branch would be
used to connect the phone with the device permanently and the other branch would be used for occasional recharging so that recharging could happen without having to remove cables from the phone nor from the device) that would allow me to charge the phone while keeping the data line from the device to the phone.
It seems that such cable exists for other phones, e.g. www.valarm.net seems
to sell such cables for Sony or Samsung (but note that the cable depends on
the phone, i.e. the Sony Y-cable is not the same as the Samsung Y-cable).
Are anyone aware of Y-cables that would allow this ?
I would be most grateful for any kind of comments/ideas on this. Thanks
a lot in advance.
Kind regards, J

Jawp said:
Hi,
I realize that this forum is a better match for a question that I posted earlier in a more general forum: http://forum.xda-developers.com/android/help/moto-g-y-cable-recharging-branch-data-t3148505. Alas, I received no replies in the former forum and I thus hope that there is a better chance that someone is able to shed more light on this in this forum.
The question goes like this:
I have a device with micro USB port and I wish to have this device
connected to a moto G (usb OTG) at all times so that I can use the
phone to relay data from the device to the Internet without any kind
of interruptions.
This works fine with a combined OTG cable with a micro-USB connection
(e.g. http://www.ttvjaudio.com/Nightscout_TTVJ_Micro_USB_to_Micro_USB_Cable_p/ttvj000001.htm) or with a micro-USB to USB male cable (from device to otg cable)
combined with a USB OTG cable (from usb male to the moto G).
Alas, the phone need to be recharged (and the phone will charge the device)
and I was hoping that there existed some kind of Y-cable (one branch would be
used to connect the phone with the device permanently and the other branch would be used for occasional recharging so that recharging could happen without having to remove cables from the phone nor from the device) that would allow me to charge the phone while keeping the data line from the device to the phone.
It seems that such cable exists for other phones, e.g. www.valarm.net seems
to sell such cables for Sony or Samsung (but note that the cable depends on
the phone, i.e. the Sony Y-cable is not the same as the Samsung Y-cable).
Are anyone aware of Y-cables that would allow this ?
I would be most grateful for any kind of comments/ideas on this. Thanks
a lot in advance.
Kind regards, J
Click to expand...
Click to collapse
Before trying to help findind an hypothetical working Y-cable, there are two issues with your needs:
a µUSB cable for host and device are different : the 4th pin is or isn't shorted to ground. so Moto G cannot behave as host or device at will, its behaviour will strictly depend on the µUSB wiring.
MotoG (stock kernel at least, no idea if anybody tried to implement it in any custom one) cannot charge while in OTG mode...
If MotoG is the device (4th pin to nothing) it will charge and get its own data accessible to an host (eg a PC)
If MotoG is the host (4th pin to ground) it will access the device data and won't charge
hope it helps

reply
Thanks. This is great input. Now, I wonder how they have managed to construct these cables for Sony and Samsung. Do you have an idea ? I will try to read up on the specifications.
Thanks again, J