Device(s): (soon) Galaxy Nexus, HP Touchpad, RAZR, Thunderbolt, Incredible, D1
Carrier: Not Provided
Thanks: 195
Thanked 702 Times in 290 Posts
Simultaneous OTG + HDMI?
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.
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.
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.
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.
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.
Quote:
Originally Posted by denzelwash
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.
Last edited by pragmatous; December 23rd, 2011 at 03:49 PM.
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.
Last edited by denzelwash; December 23rd, 2011 at 04:48 PM.
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.
Quote:
Originally Posted by denzelwash
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.
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.
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:
Quote:
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.
@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.
@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? 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.
Been looking for the all-powerful mini-computer dock myself.
Without splicing cables and without being patient you could achieve the mini-computer effectively using:
MHL for HMDI + power
Bluetooth for keyboard + mouse
Wifi for data and such by having a otg network USB hub
It's a bit more overhead, but it would work.
I haven't tried it as I'm patient and waiting for someone to build that all-in-one magic docking station. The only potential problem with the above solution might be the fact that you are using a lot of the phone's hardware at once and may run into heat issues.
Forgot I was a member here and found this thread while trying to accomplish the same thing, USB mouse/keyboard/etc AND the MHL adapter going to a TV for a makeshift "computer".
I think I've just come full circle on why this won't work. Pinout of HDMI uses 5 conductors, and there's a 5-pin USB port on the phone. If HDMI is coming out of the phone and is using all 5 pins, that leaves no conductors for USB data such as a flash drive, mouse, keyboard, etc. Not to mention that upon further inspection, the OTG cable female A side (typical USB 2.0 port) I have only has, wait for it.... 4 conductors. So even IF I could find an adapter or make my own, there aren't even enough conductors in the OTG cable, yet alone the standard USB hub. And even if there were, the phone is using all 5 pins to transmit audio/video out anyway so there's no more room for USB data.
Forgot I was a member here and found this thread while trying to accomplish the same thing, USB mouse/keyboard/etc AND the MHL adapter going to a TV for a makeshift "computer".
I think I've just come full circle on why this won't work. Pinout of HDMI uses 5 conductors, and there's a 5-pin USB port on the phone. If HDMI is coming out of the phone and is using all 5 pins, that leaves no conductors for USB data such as a flash drive, mouse, keyboard, etc. Not to mention that upon further inspection, the OTG cable female A side (typical USB 2.0 port) I have only has, wait for it.... 4 conductors. So even IF I could find an adapter or make my own, there aren't even enough conductors in the OTG cable, yet alone the standard USB hub. And even if there were, the phone is using all 5 pins to transmit audio/video out anyway so there's no more room for USB data.
Someone prove me wrong?! Please!!!
This is the reason why Samsung broke compatibility with MHL for the Galaxy S3. It uses an 11pin micro usb connector, so that given an official Samsung S3 MHL adapter, you could use OTG and HDMI at the same time. NO aftermarket product that uses 5-11 pin adapter concoctions will allow OTG + HDMI. As well, any other phone with only 5 pins cannot electrically do both, as you are discovering.
This is the reason why Samsung broke compatibility with MHL for the Galaxy S3. It uses an 11pin micro usb connector, so that given an official Samsung S3 MHL adapter, you could use OTG and HDMI at the same time. NO aftermarket product that uses 5-11 pin adapter concoctions will allow OTG + HDMI. As well, any other phone with only 5 pins cannot electrically do both, as you are discovering.
...a big FAIL by all the big handset manufacturers. Short-sighted knee jerk solution. Lack of design and forward thinking.
The simple solution would be to provide 2 micro usb ports on the device, one could be labelled usb/mhl.
There's no tech reason for smartphones not to have all the connectivity available on a pc. This includes usb, external monitor, line in/mic...
No hablo muy bien ingles, por eso solo escribiré en español. También tengo un GS3 y encontré un vídeo y una guía en internet dónde al parecer logran hacer funcionar el HDMI con el OTG al mismo tiempo.
Soy nuevo en el foro (me registré solo para poder darles el vídeo) y no puedo publicar links así que para encontrar el vídeo busquen en Youtube un vídeo llamado: "diy smart dock for galaxy s3". Lo intentaré hacer apenas lo entienda.
The Galaxy Nexus is the third official phone contracted by Google and the first phone to come with Android 4.0 Ice Cream Sandwich. Specs include a 1.2GHz dual-core processor, 1GB of RAM, 16/32GB of internal storage, a 4.65 inch 720p HD Super AMOLED... Read More