Battery Powered Usb Pocket Hub


GCDKraven

Still Fresh
Joined
Dec 19, 2006
Messages
19
Hi all,
I did a brief search through these forums to see if I could find a thread similar to this one and I didn't see anything that looked remotely close (to clarify that I do not intend to "repost" or what-have-you)

Okay.... the problem was a common one: running a high quality Wifi USB dongle on the GP2X.

I bought the EXT/USB cable from ARTaylor.... measured the output at 3.3v from my GP2X. So I made a small circuit using one resistor, one diode, 1x USB Type A female socket, 1x USB Type B female socket and 1x 4xAAA battery holder (along with a pack of 4 2500mAh Energizer batteries).

Got a little over 5.1v which is ample, and I made it measure (With the addition of a few more components) to output a stable usable 500mA. This means that even the most power-consuming USB devices can run on it, including those Host-Powered USB hubs.

I feel that a little more work and I could make some 4 port 500mA hubs ready for selling (just to cover costs) if anyone is interested?

The tests I performed are:

1) Will it power and run a USB Optical Mouse (YES)
2) Will it power and run a Wifi dongle (YES)
3) Will it power and run a laptop external hard drive (YES.... AND THAT'S MY FAVORITE PART!!!)
4) How long will it power my USB Controlled LED mood lamp (5 hours at full draw)

If anyone is interested, I just want it to be known. Or if you have any other ideas/problems/suggestions that would be great too!

When my stupid Digicam comes back from the shop (being repaired AGAIN) I will take some snapshots of the thing running in various situations.

I'm really hyped up though because now I can take 160GB of music/movies/games etc. with me wherever I go and use them on my GP2X.... and everything fits in just one pocket (excluding the GP2X itself of course).

Finally I'd just like to say I'm not plugging my wares in here or anything! I just wanted to make sure y'all are aware this is possible..... and if you would like I can post a detailed diagram + intructions of how I made it work, and how to make your own of course.

That's all for now and I'm off to bed.

Regards,
Simon J Stuart
 
xenonflash posted on Mar 6 2007 at 11:28 PM said:
Yeah, we're STILL waiting for the new BOB.

</grrrrr!!!!!>
 
Last edited by a moderator:
It isn't news, nor probably financially viable. For us, not you. Don't feel badly, it is nearly impossible to find stuff on a forum, especially without google searching (site:gp32x.de/board This link says 145,000 hits, a lot.)

If you want to make your own, here it is, my mod was moved directly to the FAQ section where no-one ever goes: DIY USB Thread. I realize that it is unfinished and I have yet to make a circuit with the protection IC in it, but it is functional, I copied mp3s to and from a memstick, and also used a mouse and PS1 pad with USB yesterday.

I just used the battery pack directly because I measured it within spec (to get some Idea of what I mean have a look at a few PC USB ports, hmmph). I suppose you have added a boosting cap because you are using a wifi stick. 4xAAA 1,000mAh NiMH pack. It powers my IBM optical mouse with cool blue scroll wheel, that should draw some energy. I have also used it with that 4-port hub to copy from one USB stick to another.

See here for a commercial USB hub, while AAA it should still be useful.

Cyberpower battery USB hub.

I see that you aren't talking about USB host, but just so everyone knows, Artaylor makes the USB host cables.

And I have sourced a termination Integrated Circuit, $0.79 at digikey.com I believe (note, $5 Handling charges apply to orders under $25, so order a couple, or some other stuff with).

Here is a pic of the termination IC, Go large.
PDR_3950.JPG


And again (Large Size)
PDR_3951.JPG


I would like to see your circuit, so do put up some pics sometime, and I am surprised you didn't build your own USB cable, but I guess you couldn't find instructions (schema reside in gp2x.wiki, see sig for link). Maybe now you will simplify your circuit and remove the 2 unnecessary USB connectors :), less bulk.
 
Last edited by a moderator:
Nubie does your design allow for adding a tv out cable. Also could it be done by someone with very limited electrical skill?
 
Jackd posted on Mar 6 2007 at 10:37 PM said:
Nubie does your design allow for adding a tv out cable. Also could it be done by someone with very limited electrical skill?
Yes, just connecting 5 wires. Or optionally for a standard Yellow/Red/White A/V cable just 4 wires and a small ceramic capacitor.

For TV ^^. If you can solder without burning yourself or melting chips you are a good candidate to do it yourself. I suppose I need an Instructables account and a Macro Camera (I keep borrowing one).

For USB host it is 5 wires for the data and ground. 2 more for a power box like you see.
 
Last edited by a moderator:
i would be interested if it chewed through 2AA rather than 4AAA. i realize it would not last as long on 2AA if you bumped the voltage output of them up to the same 5v you're getting out of 4AAA.

but then i'd only have to carry AA batts!

edit: yeah, where's the official BOB? i thought gamepark's strength was hardware, heh
 
starpause posted on Mar 7 2007 at 08:25 AM said:
edit: yeah, where's the official BOB? i thought gamepark's strength was hardware, heh
Never was, the GP2X is full o stupid crap still. (USB can be internal for a start, only $5 more to the consumer)
 
Last edited by a moderator:
GCDKraven, I'm interested in how you designed it, and how big it is. Please post details, and pics when you can. You might want to think about helping out the wiki article on it, since last I looked, the wiki was very unclear on several areas.

Good job making it work!
 
I've just done the exact same thing although its still a beta version. :eek:. Mines slightly different. I used 4 AA batteries instead of AAA. Being able to power an external Hdd is definetly nice althougth mine is only 40GB its more than enough for me at the moment. It is interesting that 2.5" Hdd have a similar foot print to the gp2x. When I work out if you can use picasa web album in linux I will post some pictures of my rig.

 
I shall post a full schematic as soon as my digicam is repaired and sent back to me!

I would like to point out that I will be altering my design to work as a "dongle" which instead of requiring a seperate cable for the EXT/USB conversion, will work strait from the EXT. (corrected)

Also since it seems quite important, I may even be able to include an S-VIDEO or Composite socket on the dongle case as well wired up for TV-OUT.... though I haven't really played with TV-OUT yet.

Will get back to you on this :)

Thanks for all the replies so far as well :)
 
nubie posted on Mar 6 2007 at 10:45 PM said:
Jackd posted on Mar 6 2007 at 10:37 PM said:
Nubie does your design allow for adding a tv out cable. Also could it be done by someone with very limited electrical skill?
Yes, just connecting 5 wires. Or optionally for a standard Yellow/Red/White A/V cable just 4 wires and a small ceramic capacitor.

For TV ^^. If you can solder without burning yourself or melting chips you are a good candidate to do it yourself. I suppose I need an Instructables account and a Macro Camera (I keep borrowing one).

For USB host it is 5 wires for the data and ground. 2 more for a power box like you see.
Ya an ultra detailed guide would be awesome. Especially if it detailed how to add the tv out to it.
 
Last edited by a moderator:
Jackd posted on Mar 7 2007 at 05:51 PM said:
Ya an ultra detailed guide would be awesome. Especially if it detailed how to add the tv out to it.
Um, I just added the S-Video to mine (and then played it for a couple hours :D).

It was easy because one of the video lines has a nice fat solder pad (think Xbox mod-chip silver squares).
It was only 3 wires becuase I cheated and soldered the grounds together(and across one of the "audio" grounds as well). I don't think that hurt anything, but it is hard to be subjective on the 84" projected image I call my TV (I only view VGA through it normally, from an HD tuner, Dreamcast, PC and VGA modded Xbox)

I figure you can either solder the sound at the EXT too, or just plug into it up top because the speakers don't shut off unless you plug something in there anyway.

The Samsung cable I got is looking not good for people not comfortable with small soldering. I have been doing it for years and had my share of soldering a PS1 9000 series IC all the way across connecting like 20 pins (ick, I had to go buy some de-soldering wick before I gave that guy back his PS1).

If a large source of these could be turned up it would be great for a production line though. The only way to connect this plug properly is to make a circuit board up and have surface mount components soldered onto it. Then a mini-switch for A/V to S-Video and a tiny capacitor to change it, and the USB termination IC could all fit nicely on that board and solder pads for all of them could come off of it. (4 wires USB, 7 for proper audio and S-Video).

Another person on these forums has got ahold of a Samsung USB cable for the e810, it looks to me just like the TV-Out cable from GPH, so it is all set for soldering individual wires onto the pins, not a circuit board.

This might be a better hobbyists EXT connector, and we could still mount the ~1.5x2.2mm Integrated circuit on a board small enough to fit inside the EXT shell once we closed it up.

All GPH needs to do is add a ~$2 worth of components to the TV-Out cable and sell it for ~$10-15 more than they are now, the profit margin is HUGE, I wish they would too, I would buy one.
 
Last edited by a moderator:
What were the american coins used for?

I can go into a little detail on how to build one (still not got my camera back). Here's the ingredients list:

Ingredients:
1) 4x AA (or AAA) battery holder with +/- wires
2) if battery holder doesn't have a switch on it, get a simple switch (1 or 2 pole, 2 position - on/off)
3) 5.1v Zener diode
4) 1.3w Zener diode
5) 100ohm resistor
6) USB Type A female (standard USB socket)
7) USB Type B female (smaller USB socket such as used on printers etc.)
8) A USB cables (Type A to Type B - both male)
9) A small amount of stripboard
10) A multimeter (voltometer)

Amercians can get all those things from Radio Shack, but for the British, I recommend www.rapidonline.com because that's where I got my order from and everything worked brilliantly. As for other countries, I'm affraid I've no idea what your best supplier will be.

Okay until I get my camera back you'll have to use some iniative and look up a pinout for both a female type A USB socket, and a female type B.... http://pinouts.ru/Slots/USB_pinout.shtml

Without a camera I can only give you a diagram image:
http://www.rustybin.com/usbhub.bmp
If for some reason this image fails to show, send me a message and I'll sort it out (I'm hosting it on my server)

I think this about covers a basic battery powered USB hub! Check the voltages carefully before connecting it to a device, and I don't take any responsibility for any damage that may occur (covering myself leagally).

Enjoy

More later

Regards,
Simon J Stuart
Grey Cascade Designs
 
Back
Top