HDMI and USB at same time

emil_b

Member
Dec 31, 2006
30
8
8
Hi,

Saturday I had some time to open the HDMI dock (for Galaxy Tab 7) and mod it to have alternative power input.
After that I was able to use the HDMI output and USB host at same time. The setup is:
- HDMI out for Samsung TV
- wireless USB keyboard
- external HDD connected with a powered HUB
In this setup I was able to use the keyboard and video files from external HDD while watching on TV screen.

The only problem is that the "MTP Application" notification is still there and the tablet is not full powered from external power supply, it discharges slowly the battery.
After some investigation I've seen that on the original charger there seems to be some resistors between USB lines and Vusb and GND. If I connect the original charger (not inserted on power outlet) the tablet is full powered and the MTP Application is not displayed (when I put the tablet in dock). After that if I remove the cable and insert the USB host cable everything is OK and tablet is full powered with USB host and HDMI working.
The docking is powered with 5V/2A PDA DC adapter.

When I'll open the dock again I will make some picture.
Your are welcome for questions and suggestions.

Emil
 
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THEDEVIOUS1

Senior Member
Nov 26, 2009
808
928
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HOW MUCH?

Cant believe this is my first post on any message board EVER but what better reason! First i would like to know how much would u charge to make the modification for me? I would provide the dock and any other materials that u need of course. Secondly, since the dock works with ALL tab variants(PERSONALLY ONLY TESTED WITH P1000, P7100, P6200, P6210 BUT 99% CERTAIN), u might want to post your development in every other versions forum. I believe this would generate a LOT more interest in this project because there actually has already been a few threads created in which several attempts were made but no one could find the magic combo(plus it could mean a few extra bucks in your billfold!). I waited to post in hopes that u would update with pictures and/or a tutorial but still would rather you perform the actual surgery. Congratulations on accomplishing what samsung should have done from the start...a TRUE multimedia dock! I guess the only suggestion i could offer is if it were possible to actually add a few usb ports into the base of the hdmi dock itself, which is how i feel samsung should have made it originally...definitely not a priority.

Here are a few reference threads if interested & i've already provided a link in each one pointing to your original post for those interested (hope u dont mind!)
http://forum.xda-developers.com/showthread.php?t=1610832

http://forum.xda-developers.com/showthread.php?t=1155065

http://forum.xda-developers.com/showthread.php?t=1149442
 
Last edited:

emil_b

Member
Dec 31, 2006
30
8
8
Sorry, but I can't do this for you.... It's complicated.
Now I work to found a solution to put an USB connector on the dock and to put a power connector to.
The big problem is that the tab enters on MTP mod when powered this way. As described on other threads there is a way with USB lines to activate full external power.
When I'll have a full modification dock I'll put some pictures and instruction for that.
 

emil_b

Member
Dec 31, 2006
30
8
8
Galaxy Tab Dock modified

Now I have a full functional dock, modified.

So, after receiving the Galaxy Tab Plus media dock from ebay I've found that I can change the tab fixing part with the one on the old Galaxy Tab Dock.
So, now I have old Galaxy Tab multimedia dock full compatible with my Galaxy Tab Plus.

Then I modified the dock to include standard power jack and standard miniusb connector for OTG.

The USB Host is powered from the external power supply, this helps to not discharge the battery when using tab and slow charging.

I made some pictures with details for connections and modification.
You can view at:
http://www.flickr.com/photos/buzdumil/sets/72157630734690786

There was some work to do...is not very easy. The best thing that can be done is to make a PCB. That PCB, at in my pictures, could be fixed near metal weight. Also there the clips of the case need to be cut, but there is no problem because at same position exist screws for fixing.

The problem with MTP application started when power connected or tab inserted on dock remains. But now is easier to use external HDD, usb keyboard & mouse and television to watch movies.
 

YellowRex

Member
Sep 17, 2009
38
0
0
That's amazing, Emil! That's the dock accessory Samsung should have sold in the first place. After looking over your pictures, I'm ready to go order a soldering iron and get to work!
 

MRBR7

Senior Member
May 27, 2012
190
32
0
Hi emil b just letting you know i was playing around with my dock and found how to get rid of the red x from when power is applyd.
First connect power and get red x....
Then disconect the earth and re connect it again..
This forces AC Charge mode...
No resisters or shorting data lines are needed..
So good for being in host mode...
All you need to do is put a on/off switch inline on the earth
Where you supplied power to the dock.
Doesnt need to be inside the dock..
Give it a try and let me know...
Just have to play with it and hit switch a couple of times...
 

mr_esmit

Senior Member
Nov 18, 2010
151
4
0
Im looking at all options concerning the modification of this dock. One question that comes to mind is: If I only use the red and blackwires to send power to the USB connector, will I still be able to use the OEM 30 power connector??
 

cypher_zero

Senior Member
Jan 12, 2011
55
168
0
OP, I am going to attempt to make this modification myself. Would you be able to provide any additional instructions/suggestions to the pictures up on Flickr?

Thanks,
cypher
 

MRBR7

Senior Member
May 27, 2012
190
32
0
Im looking at all options concerning the modification of this dock. One question that comes to mind is: If I only use the red and blackwires to send power to the USB connector, will I still be able to use the OEM 30 power connector??
No because the origonal charger has the resisters on the data lines...
you are better to add just power to pin 7(9) and earth to pin (1)30..
then add a otg dongle..