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Simultaneous OTG + HDMI?

altimax98

Android Enthusiast
Jan 11, 2010
718
615
Lakeland Fl
So with the MHL port instead of the USB + HDMI ports like Motorola uses, we cant use OTG and HDMI at the same time. But is this a Software/hardware limitation (ie- kernel doesnt support it, or the phone physicly will not do it) or is it just Hardware (ie only a MHL port)?

My thought was wouldnt we be able to use the HDMI vertical dock which has the USB out the back, and the HDMI on the side to do simultaneous OTG and HDMI? I really hope this can be done for emulators and such. Xbox360 controller + N64oid on my Big screen :). Anyone know if this would work, or if anyone buys this dock, can you try it out?

The only thing, i think about is that most MHL ports require external power. If thats the case then the USB port on the back might not support a OTG mode :(
 
I'm wondering the same thing, as I want to use my 21" computer monitor and be able to use a USB mouse/keyboard and/or USB flash drives.

I'll post when I try, but I'll have to wait for ICS to support USB host. There was a kernel where they added it, but it was causing battery drain so they disabled it.

My OTG adapter is shipping, and I'll get the MHL adapter soon.
 
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I'm wondering the same thing, as I want to use my 21" computer monitor and be able to use a USB mouse/keyboard and/or USB flash drives.

I'll post when I try, but I'll have to wait for ICS to support USB host. There was a kernel where they added it, but it was causing battery drain so they disabled it.

My OTG adapter is shipping, and I'll get the MHL adapter soon.

My otg adapter showed up yesterday, still waiting on the mhl. Usb host worked fine for me with a usb gamepad and a keyboard. If mhl doesnt work at the same time as usb otg, you could use a bluetooth keyboard and mouse, they work fine as well.
 
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So with the MHL port instead of the USB + HDMI ports like Motorola uses, we cant use OTG and HDMI at the same time. But is this a Software/hardware limitation (ie- kernel doesnt support it, or the phone physicly will not do it) or is it just Hardware (ie only a MHL port)?

My thought was wouldnt we be able to use the HDMI vertical dock which has the USB out the back, and the HDMI on the side to do simultaneous OTG and HDMI? I really hope this can be done for emulators and such. Xbox360 controller + N64oid on my Big screen :). Anyone know if this would work, or if anyone buys this dock, can you try it out?

The only thing, i think about is that most MHL ports require external power. If thats the case then the USB port on the back might not support a OTG mode :(

If you're rooted you can use a bluetooth ps3 controller with the sixaxis controller app on the market. The controller has to be manually paired via usb once, but this works with otg, so you don't need to use a pc to do it. I tried it last night and it worked after i messed with the settings for a few minutes.
 
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Can you guys post links to OTG and MHL adapters that have been verified to work with the Nexus? :) That would be really helpful.

I bought the $7 one on amazon and it works great..

About the Bluetooth I have a Xbox360 and not to fond of Bluetooth. I've always noticed a slight delay and lag on android with BT peripherals
 
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Just so you know

Amazon.com: Micro USB to HDMI MHL Adapter: Electronics

It has a micro usb on the side of the block. Pretty much solves the OTG + HDMI problem.

The micro usb on the side is to power the MHL adapter. It doesn't work without a charger connected, so that doesn't exactly solve the OTG problem. There may be a way to run both with a splitter or adapter.

I just confirmed the overstock.com mhl adapter works with the galaxy nexus btw, although it's now out of stock.
 
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Technical Details
Connect your MHL ready device to your HDTV for larger and wider viewing content
Share photos, videos, music, and presentation to a larger crowd
Supports maximum resolution upto 1280x720p and all bandwidth between 25-75Mhz
Extra micro USB port for charging and syncing all while connected to your HDTV
Most popular HDTV connection adapter

It even says it in the product description:

The MHL adapter also has an extra micro USB port so you can still charge or transfer data simultaneously all while connect to your HDTV.

The micro usb on the side is to power the MHL

adapter. It doesn't work without a charger connected, so that doesn't exactly solve the OTG problem. There may be a way to run both with a splitter or adapter.

I just confirmed the overstock.com mhl adapter works with the galaxy nexus btw, although it's now out of stock.
 
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Technical Details
Connect your MHL ready device to your HDTV for larger and wider viewing content
Share photos, videos, music, and presentation to a larger crowd
Supports maximum resolution upto 1280x720p and all bandwidth between 25-75Mhz
Extra micro USB port for charging and syncing all while connected to your HDTV
Most popular HDTV connection adapter

It even says it in the product description:

The MHL adapter also has an extra micro USB port so you can still charge or transfer data simultaneously all while connect to your HDTV.

It doesn't work that way. You have to have a charger connected to that port to get a picture on your display.

Edit: If you hook up a powered hub, you may be able to run an OTG adapter, but you have to have power going into the MHL adapter one way or the other.
 
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Maybe the one on amazon is not the same as the one on overstock.com then. The product description is very clear that you can transfer data using the micro usb port or use it to charge the device. if it doesn't do that then that is false advertisement.

You can get into a lot of trouble for doing that.

It doesn't work that way. You have to have a charger connected to that port to get a picture on your display.

Edit: If you hook up a powered hub, you may be able to run an OTG adapter, but you have to have power going into the MHL adapter one way or the other.
 
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Maybe the one on amazon is not the same as the one on overstock.com then. The product description is very clear that you can transfer data using the micro usb port or use it to charge the device. if it doesn't do that then that is false advertisement.

You can get into a lot of trouble for doing that.

Must be false advertisement, or perhaps device dependent then. The single review of that adapter makes mention of the requirement that the charger be plugged into the MHL adapter.

Googling shows that the charger requirement for MHL adapters is pretty standard. If it's possible, someone will probably make a combination OTG and MHL adapter with all the ports on it.
 
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I got this one from Amazon. Of course, it's not available anymore, but it does work! USB keyboard, mouse, and flash drives were all used successfully. :D

Now I need a hub, so I can use more then one at the same time, and a powered one too, so I can try USB OTG and MHL at the same time.

I'll let you know as I'm able.

EDIT: That OTG adapter I bough looks like this one from Overstock. Take that as you will, I don't know for sure.
 
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I got this one from Amazon. Of course, it's not available anymore, but it does work! USB keyboard, mouse, and flash drives were all used successfully. :D

Now I need a hub, so I can use more then one at the same time, and a powered one too, so I can try USB OTG and MHL at the same time.

I'll let you know as I'm able.

EDIT: That OTG adapter I bough looks like this one from Overstock. Take that as you will, I don't know for sure.

This sounds pretty awesome... what are somethings people would use a mouse for though?

Have you confirmed that the OTG adapter works with this setup?
 
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This sounds pretty awesome... what are somethings people would use a mouse for though?

Have you confirmed that the OTG adapter works with this setup?
People would use the mouse if say, they are running HDMI to their computer monitor or HDTV, thus allowing them to use their phone as a mini-laptop (my plan). It's kind of useless on a small screen, IMO, other then being "cool" to show off. A full size keyboard is VERY handy, even on a small screen, for when you have to type a lot, assuming you can can type on a standard keyboard faster then your phone screen, that is.

Current update: I have just ordered a couple USB cables, a USB hub, and an MHL adapter. I'll have the hub on the 6th, but I won't get the MHL adapter until the 10th-13th.

My current plan is to connect the MHL adapter to my phone, and then plug the OTG adapter into the micro usb port on the MHL adapter. I will then take two USB extender cables. On cable A I will cut off the female end, and splice the power wires from cable A into the power wires on cable B, leaving cable A's data wires intact. Cable B will otherwise be unmodified, and the male end of B will plug into the OTG adapter, while my USB hub will plug into the female end of B. This way I will have power supplied to both the hub and the MHL/phone, while allowing data between the MHL adapter and USB hub.

This all assumes USB data from your phone is allowed through the MHL's USB port. I got this one, and it says:
Extra micro USB port for charging and syncing all while connected to your HDTV
So I'm assuming it does allow data to go through that port. We'll see.

I'll update when I have news, and post pictures to prove it works if it does.

To the OP: Sorry if I'm hijacking your thread, I'll post my own if you mind what I'm doing.
 
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@jseyfert3 - I like your innovative thinking, but there's a caveat. Syncing involves the phone acting as a peripheral connected to a host whereas what is being attempted here is to allow the phone to act as a host to other USB devices. I can see where the MHL adapter will allow USB communication because the standard calls for MHL-enabled TVs to be able to receive an HDMI signal from the connected device, provide power to said device, and be able to send commands to said device (ie. controlling playback through the TV and thus the TV's remote). If I'm not mistaken, the USB OTG cable is more than just a USB female to micro USB male adapter. Does it provide some sort of configuration in the micro-USB connector for the purpose of putting the device in host mode vs peripheral mode? That may be lost when the MHL adapter is in between. MHL + OTG is probably possible, but it really needs a custom engineered adapter.
 
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@kyler13: I do not know if the OTG adapter has any built in circuitry or not. I do remember reading something about that in the specs, but I'm not sure if it's actually required. I think it's quite possible the phone is "smart" enough to tell, and doesn't need anything special, but now I'm just talking out of my ass.

I honestly do not know. However, I don't easily give up, and I'm still going to try.

If it doesn't work, I thought I'd try putting a splitter before the MHL adapter, but of course this may not work as well. And if this doesn't work either...well, at least it's already been proven USB hubs work, so I can hook multiple USB devices to my phone, and I'll be able to use HDMI out, although I'd have to get a bluetooth keyboard and mouse.

Either way, what's the point of buying an Android phone if you're not willing to experiment? :D For example, in addition to the above, I also have a palm touchstone cover and touchstone charging base on order, and I'll be modding them into my GN so I have inductive charging capability, which would just be cool. :cool:
 
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