The specification on their website:
http://dx.com/p/jxd-s18-4-3-resisti...ad-tablet-pc-w-tf-wi-fi-g-sensor-black-161536
Teardown time!
RockChip RK2926 AE4T278 1245 (soc)
T659102 A1 TI 2GI A70T G4 (chip power controller)
Realtek RTL8188EUS 802.11b/g/n (wlan over usb 2.0 host, yes rk29xx supports up to 3 usb devices! 2x host 1x otg but they are not connected)
2x Geil 256X8DDR3 WT 1248 <CG1L256M88BA15DH> (ram)
Hynix H27UBG8T2BTR BC 250A (nand flash 2gb i believe)
F88_V1 <2012.12.06HM FS 1552> (pcb itself)
ZBH043GT-12 V1 (blacklight type: led 50k before eol, res; 480*272 4.3'' lcd)
Mali 400 MP2 (gpu)
Battery 3.7v 1100mah lithium ion
Pictures!
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Take care guys.
Hi and thank you !
do you know if the usb port is the OTG one ?
i try to figure out how to add bluetook or gps on this device, maybe if anyone know where are the free usb pins ..
Bizen-Ya said:
Hi and thank you !
do you know if the usb port is the OTG one ?
i try to figure out how to add bluetook or gps on this device, maybe if anyone know where are the free usb pins ..
Click to expand...
Click to collapse
I have the same problem i know that the realtek wifi device is usb connected to the soc but other then that i cannot find any other options of ways of connection more devices to it. I cannot find a datasheet of this chip on the www. And i have no idea what the right pins are. Maybe we can connect a hub to that usb port what is used by the wireless device and do it this way but i have no idea if this will work.
And no out of the box this little tablet does not have OGT.
The soc in fact does support's it (2x host 1x OGT) but it is not connected to anything on this pcb design. If i knew the pins i would surely try to mod it.
Thank you for providing information to everyone
ok, i have OTG working now..
this is just a power issue, i haved used a OTG+Power cable, that's working fine
next step, make the bluetooth dongle working ...
Bizen-Ya said:
ok, i have OTG working now..
this is just a power issue, i haved used a OTG+Power cable, that's working fine
next step, make the bluetooth dongle working ...
Click to expand...
Click to collapse
The OTG really works with this type of cable?
If so, then we should be using bluetooth dongles easily (as long as the firmware supports it or has drivers that can detect it)
Going to try the OTG+power cable, this would really make a difference in terms of usability.
Also guys the stock battery is weak. I replaced it with "2500mAh Rechargeable Li-ion Battery for Samsung Galaxy S 3 III I9300", only had to ditch the speaker, since the battery is quite bigger.
Lemzy said:
The OTG really works with this type of cable? View attachment 2314266
If so, then we should be using bluetooth dongles easily (as long as the firmware supports it or has drivers that can detect it)
Click to expand...
Click to collapse
No this wont work on the S18 tab. But yes if you replace the wireless realtek module and for example connect a hub to those pins and if android has the firmware you could connect more devices to the hub. Not sure if this will work through.
swcdude said:
Going to try the OTG+power cable, this would really make a difference in terms of usability.
Also guys the stock battery is weak. I replaced it with "2500mAh Rechargeable Li-ion Battery for Samsung Galaxy S 3 III I9300", only had to ditch the speaker, since the battery is quite bigger.
Click to expand...
Click to collapse
But really nice let me know some progress it indeed makes a huge different in use usability, i also replaced the battery with a 1800mah ion battery from a dead tom tom system(broken display), that had the same voltage(3.7) but the battery was dead so i had to put back the default one since i didn't had anything else that did fit in this tiny little tab haha.
Sorry for the quite slow response.
thank you very much
NiTrOwow said:
No this wont work on the S18 tab. But yes if you replace the wireless realtek module and for example connect a hub to those pins and if android has the firmware you could connect more devices to the hub. Not sure if this will work through.
But really nice let me know some progress it indeed makes a huge different in use usability, i also replaced the battery with a 1800mah ion battery from a dead tom tom system(broken display), that had the same voltage(3.7) but the battery was dead so i had to put back the default one since i didn't had anything else that did fit in this tiny little tab haha.
Click to expand...
Click to collapse
So is it possible to connect a game controller through the OTG + Power cable?
Lemzy said:
So is it possible to connect a game controller through the OTG + Power cable?
Click to expand...
Click to collapse
Please see the image of the soc. It does not have OTG on default. You have to got the datasheet and solder a OTG port on the soc itself.
That's actually the only thing that sucks about this device. No OTG, out of the box and no soc datasheet. Limilted support to all of the internal stuff itself. Is what makes it less fun for most of us. We are no pro's or people who are really good in reserving without a little bit of documentation or help. I would be glad if JXD would release more stuff about this device so more people can take a look at it and have fun with it in a diffrent way because the device itself it pretty useless out of the box in my opinion.
As i already said Otg is working fine on mine ....
I have sucessfully used my s18 with a USB GPS + powered USB otg cable and usbgps4 droid
Bizen-Ya said:
As i already said Otg is working fine on mine ....
I have sucessfully used my s18 with a USB GPS + powered USB otg cable and usbgps4 droid
Click to expand...
Click to collapse
So you're saying that otg worked on your S18-03-XXXX device?
Strange i still did not had time to check it yet. And is also is strange because manufacturer does not say it had any. The soc is capable of 3 otg devices on the host but those aren't connected following all the technical details i read on their website and other re-seller's website. If you pull the device brand new out of the box and connect a otg device it should not work according to the manuals and details on their website, or they changed the pcb design and newer version has this feature enabled.. Can you post your model number?
Otg works with external power
I hope this is no considered spamming, as I posted same info on other thread.
I have s18-03-201305-4GB-01748.
I guess they are not listing device as otg capable because device is not delivering any power to otg devices, so you need always power injecting cable. Otherwise device is not anyway restricted. Actually firmware has quite extensive hardware support as you can see by browsing driver folders on device.
I registered just to tell you that otg works perfectly with power injecting cable. Tested 2 TB NTFS drive and apple usb - Ethernet dongle. Both work well. Also you can use this device as WiFi ap with Ethernet dongle. I am planning to use this as portable server. I just hope somebody gets interested making updated firmware.
I may be repeating but I say once more. There is no need to do any hardware hacking to get otg working. Just get power injecting USB cable. You might have to put WiFi off and back on to get your USB device connected. I think this triggers device initialization.
Frank Blah said:
I hope this is no considered spamming, as I posted same info on other thread.
I have s18-03-201305-4GB-01748.
I guess they are not listing device as otg capable because device is not delivering any power to otg devices, so you need always power injecting cable. Otherwise device is not anyway restricted. Actually firmware has quite extensive hardware support as you can see by browsing driver folders on device.
I registered just to tell you that otg works perfectly with power injecting cable. Tested 2 TB NTFS drive and apple usb - Ethernet dongle. Both work well. Also you can use this device as WiFi ap with Ethernet dongle. I am planning to use this as portable server. I just hope somebody gets interested making updated firmware.
I may be repeating but I say once more. There is no need to do any hardware hacking to get otg working. Just get power injecting USB cable. You might have to put WiFi off and back on to get your USB device connected. I think this triggers device initialization.
Click to expand...
Click to collapse
Thanks Frank and Nitrow.
Yes, don't give up too quickly when testing Host mode on USB ports.
They might have no charge pump, an inadequate charge pump or inadequate capacitance for inrush current.
You usually will need an OTG adapter to ground the ID pin.
A power splitter cord will work, but you can't usually find one locally.
I use a "back-powering" hub.
That's a cheapy hub that has the protection diode bypassed.
Some really cheap hubs already have it shorted.
See: http://forum.xda-developers.com/showpost.php?p=25639514&postcount=8
Try a keyboard first because they draw minimal current and they have a simple driver.
Some flash drives and GPS units are real current hogs.
Renate NST said:
Yes, don't give up too quickly when testing Host mode on USB ports.
They might have no charge pump, an inadequate charge pump or inadequate capacitance for inrush current.
You usually will need an OTG adapter to ground the ID pin.
A power splitter cord will work, but you can't usually find one locally.
I use a "back-powering" hub.
That's a cheapy hub that has the protection diode bypassed.
Some really cheap hubs already have it shorted.
See: http://forum.xda-developers.com/showpost.php?p=25639514&postcount=8
Try a keyboard first because they draw minimal current and they have a simple driver.
Some flash drives and GPS units are real current hogs.
Click to expand...
Click to collapse
Yes but i wanted to make a dedicated otg connected hard-wired to the print. but those connections (pins) on the board are too small and i can still not find a soc datasheet for the rockchip. I searched on the entire internet. It still isn't there...
Step one is to get USB host mode working any way you can.
Then you can discuss hacking it internally.
The other USB ports may be internally hubbed and not do host mode.
They may not have Id connections and you'd have to hack the driver/issue device commands.
Renate NST said:
Step one is to get USB host mode working any way you can.
Then you can discuss hacking it internally.
The other USB ports may be internally hubbed and not do host mode.
They may not have Id connections and you'd have to hack the driver/issue device commands.
Click to expand...
Click to collapse
That's not the problem since it is already reported to work on never soc, i only need datasheet and chip pin-out.
http://pdf.elecfans.com/NXP/LPC2926.html
It just sucks. I will sell this thing and buy myself a beagleboard instead. That's what i probably will do.
Did any of you try to run this without an battery in the unit. So only on adapter?
I am thinking of using one as an dedicated clock.
I also want to point out that there are two versions of this device for those that don't know this.
Related
Hello,
Firstly, will this thing will work on my HD2? (of course in Ubuntu)
http://www.dealextreme.com/p/micro-usb-on-the-go-host-otg-adapter-pair-50774 <-- I have bought that ready, shipping, just conifrm that will this work
Secondly, will the usb port will provide power to the usb devices? If not, will a USB hub with a DC power input will work?
Third, are there any NON-DISPLAYALINK tech.'s usb display will work on HD2??? (Display Link have no driver for ARM's Ubuntu)
I will open a new post after the item is shipped, and it works.
Thanks.
hopkinskong said:
Hello,
Firstly, will this thing will work on my HD2? (of course in Ubuntu)
http://www.dealextreme.com/p/micro-usb-on-the-go-host-otg-adapter-pair-50774 <-- I have bought that ready, shipping, just conifrm that will this work
Click to expand...
Click to collapse
Yes, depence on the USB Cable you use (and what you want to do with it).
hopkinskong said:
Secondly, will the usb port will provide power to the usb devices? If not, will a USB hub with a DC power input will work?
Click to expand...
Click to collapse
A normal Hub is not enought for this
There are a lot of threads about this.
My favorite:
http://forum.xda-developers.com/showthread.php?p=10797562
You need to power up the HD2 side of the USB connection, because the phone doesn't provide the +5V like a normal USB host.
You can also use a y-cable (from a external HDD) and connect the second pc-connector for additional power to a +5V
source, there are also some threads around here
hopkinskong said:
Third, are there any NON-DISPLAYALINK tech.'s usb display will work on HD2??? (Display Link have no driver for ARM's Ubuntu)
Click to expand...
Click to collapse
I think I've read something in the ubuntu development thread that they want to try it, but haven't heard something about a running version
But important:
USB host is working with ubuntu, I'm using mouse and keyboard myself.
So, keep on trying
Regards
mf_1
But why that Ian hub will not work?
It have a extra power supplying port!
And I am going to buy a dc5v 2000ma(2a) dc power supply!
The power supply is only for the client side (mouse, HDD....).
Normal USB hosts provide the host side, but the HD2 doesn't.
mf_1
Yea
The host will not provide power
But my power supply will!
So my devices will ONLY get power from my dc power, not the the host!
Isn't it?
Yes, but you also need power on the host side. The controller chip in the hub is connected to the host device. (See link in my first answer)
Leo has no power on host side -> controller has no power -> client side not working, no USB device for ubuntu
But I have tried to NOT PLUG THE IN THE USB CABLE, only plug the dc power, but the hub still have led light, and the the 4 hub port still have power!
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I didn't plug the USB...
Sorry, perhaps my english isn't understandable.
For USB Standard:
The additional power supply is only for client side.
The client side is working without additional power supply, if you use clients with low power consumption, such as mouse, keyboard, some memory sticks. They use the power provide by the host.
Most HDD need additional power.
But again: Leo isn't providing a normal host, there is no power on the host side.
Regards
mf_1
But i still don't understand...
Can't the client side USE the DC power(not use the host side), the Host side is only for data
And i conifrmed that the Client side can have power without host power support!
hopkinskong said:
But i still don't understand...
Can't the client side USE the DC power(not use the host side), the Host side is only for data
Click to expand...
Click to collapse
Yes, it uses the DC power if it is connected.
hopkinskong said:
And i conifrmed that the Client side can have power without host power support!
Click to expand...
Click to collapse
Yes.
mf_1
So why you said it will not work??
thx
Just try it
mf_1
My OTG not yet arrived, but i have already Find the way to test it! it works!
I have make a pice of 1.4cm*1cm(corrected to about 0.1 cm), and i cut off the middle of the paper, so the paper likes this shape: (attachment), and it have covered the USB 1st pin and the 4th pin(POWER), and only left Pin2+3(Data), so i put this paper in my USB and i plug in my computer, it have no supply! Then i plug in the DC power into the USBHub, i also plug in a USB Mouse as the Client, it works!
hopkinskong said:
My OTG not yet arrived, but i have already Find the way to test it! it works!
I have make a pice of 1.4cm*1cm(corrected to about 0.1 cm), and i cut off the middle of the paper, so the paper likes this shape: (attachment), and it have covered the USB 1st pin and the 4th pin(POWER), and only left Pin2+3(Data), so i put this paper in my USB and i plug in my computer, it have no supply! Then i plug in the DC power into the USBHub, i also plug in a USB Mouse as the Client, it works!
Click to expand...
Click to collapse
the light on the hub is just to inform you that an external power supply is connected to it, nothing more.
a good usb hub has 2 electrical circuits, 1 on the host side (computer/hd2), and 1 on the client side (the ports).
the host side uses the power from the host to power the usb controller in the hub, and send all left over power to the client side.
this is the first circuit, which is connected to the second circuit via a diode (1 way street for power).
the second circuit has a connector to hook up the external power supply.
now if what you say is really true, the manufactorer of your hub has saved about 2 cents by removing the diodes, which are there for safety.
not having those can result in a burn out of the host controller (the 1 inside your computer).
the hd2 is a usb client device, this means the powerlines on the connector are there to recieve power (charging).
but the hub needs a host usb connection (sending power).
so you either need to make a Y cable, or modify the hub.
plopper
I haven't this problem
Am I being dense or is it possible to plug the supplied usb cable into a laptop or desktop computer and use the computer's screen and keyboard to interface with the HD2 running Ubuntu? ie software hub in laptop.
Is there a place for us to buy such a USB host from the net instead of having to perform these delicate things ourselves? I know many here are DIY people, but what about for those of us who are electronic illiterate? Anyone found a supplier for such USB hubs? Thanks
So if i buy this, will it work great?
http://www.dealextreme.com/p/solar-...t-hub-with-white-light-2-led-flashlight-48411
Robbie P said:
Am I being dense or is it possible to plug the supplied usb cable into a laptop or desktop computer and use the computer's screen and keyboard to interface with the HD2 running Ubuntu? ie software hub in laptop.
Click to expand...
Click to collapse
sounds like remote desktop, aka VNC.
erlern said:
Is there a place for us to buy such a USB host from the net instead of having to perform these delicate things ourselves? I know many here are DIY people, but what about for those of us who are electronic illiterate? Anyone found a supplier for such USB hubs? Thanks
Click to expand...
Click to collapse
the 3th post in the thread about building the hub has a hint (3th Q&A).
hopkinskong said:
So if i buy this, will it work great?
http://www.dealextreme.com/p/solar-...t-hub-with-white-light-2-led-flashlight-48411
Click to expand...
Click to collapse
any hub you buy has to be modified.
looking at the size of the solar panel it is only ment to power the 2 leds from the torch.
as i doubt it can give out the 2 amps which we need.
plopper
didnt want to order a usb otg cable. so...
whatever it takes, right? hacked this together with crap laying around.
http://imgur.com/IqaW3
updated to 3.1
http://imgur.com/jRdtR
btw, this is on a wifi xoom.
Also, if anyone is curious, the red thing is a micro usb break out board from sparkfun. the other usb thing is a expansion slot from a old motherboard. just google it. SparkFun is down right now, but i think its this: http://www.sparkfun.com/commerce/pro...ducts_id=10031.
Part Originally ordered cause of this: http://forum.xda-developers.com/arch.../t-819551.html
edit:
thought you might be interested in this too....
http://imgur.com/Ptg3H
http://imgur.com/rUIQq
this is connected directly to a Nikon D60 DSLR.
wonder what other cool **** i can plug into this
this is NOT a rooted device. yet. i want to see what it can do stock.
Diff between micro-A USB and the more common micro-B cable is that pin 5 is grounded in the first, and open in the second.
http://en.wikipedia.org/wiki/Universal_Serial_Bus#Human_interface_devices_.28HIDs.29
Short pin 5 to pin 4 to get the u-A (OTG) type. Many u-USB cables don't have pin 5 wired at all, so this may not work.
Otherwise, just buy one for a few bucks.
http://search.digikey.com/scripts/DkSearch/dksus.dll?mpart=ZX40-A-5S-75-STDAJ
http://www.dealextreme.com/p/genuine-nokia-ca-157-micro-usb-otg-to-usb-data-cable-14cm-length-51045
I'm really happy that HC3.1 now has improved I/O (USB host, MTP/PTP).
Can you break it down for me? What exactly does it do?
Sent from my PC36100 using XDA App
Any ideas where one could buy one of these cables from?
http://www.meritline.com/micro-usb-type-b-male-to-usb-a-female-cable-black---p-62877.aspx
Oh, I guess I shouldn't hijack this thread.
Could anyone with an answer reply here please?
http://forum.xda-developers.com/showthread.php?t=992415&page=2
>Any ideas where one could buy one of these cables from?
Read above.
>What exactly does it do?
http://google.com/search?q=usb+otg
Effing awesome!!! was looking for this all night, fetched a couple old mobo's but couldn't find a "single" female usb plug, maybe I'm lucky tonight..
Good to see this thread.
e.mote said:
>Any ideas where one could buy one of these cables from?
Read above.
Click to expand...
Click to collapse
But those are the micro A cables... they will not fit into Xoom, will they?
By the way, will getting a female to female work for the OTG purpose?
So have the micro B male to normal A male plugged into female of female to female, so that the other side female is available for a usb device to plug into?
http://www.monoprice.com/products/p...d=10314&cs_id=1031401&p_id=362&seq=1&format=2
Seems simple to me, but will it work? I might have a lot better chance of finding a female to female here than a micro usb OTG.
In case I didn't explain what I was talking about clearly, I made this diagram.
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*Edit
I'm guessing the answer will be no... as the default cable is probably only designed to be used as host from the normal USB Side..
i.e. the 5th pin on the micro is floating?
But... Will it work if you had a switch built into the cable that toggles the state of the 5th wire between connected to 4th and floating?
So that you could use the same cable and switch between normal and OTG..
Sort of like this:
This would take a bit of trickery to get right, but then one would only need to carry one cable and a small female to female.
Ya, I suppose you could just buy one of these:
http://www.amazon.com/gp/product/B0..._m=ATVPDKIKX0DER&pf_rd_r=1VCNAYJJHNGVY48CAHKY
(although I'm not sure if this one will actually work as it says it is an adapter and doesn't mention OTG at all...)
But I think it is too bulky at the Xoom side and and I would worry about bumping it and snapping something off inside the Xoom.
Any ideas?
I might be completely wrong in how I understand this whole thing, so feel free to tell me so.
>But those are the micro A cables... they will not fit into Xoom, will they?
Form factor difference between micro-A & micro-B:
If Xoom supports OTG, its plug receptacle should be the micro-AB variety, i.e. it should accept both A & B connectors.
If Xoom only accepts the beveled connector of micro-B type, then it's not in-spec with respect to OTG. That said, there are cables/adapters labeled as OTG and yet have the beveled connector of the micro-B type. You just have to pay attention to the actual connector. It's all a bit hit-or-miss, since USB host on mobile devices is still rare, and implementations are somewhat ad hoc despite specs availability.
>will getting a female to female work for the OTG purpose?
Can't use micro-B cable (per your pic) if Xoom is to be host device. Get correct micro-A cable for your needs.
The adapter you linked to is a simple size converter; it doesn't allow OTG capability. What you're talking about is more like these,
http://www.dealextreme.com/p/micro-usb-on-the-go-host-otg-adapter-pair-50774 (micro OTG)
http://www.dealextreme.com/p/mini-usb-on-the-go-host-otg-adapter-2-pack-50944 (mini OTG)
Note: These haven't been verified to work, unlike the previously-linked Nokia OTG cable, which has been confirmed as OTG capable. Also, as you said, these can damage the port with an inadvertent bump.
Different devices need different connectors. Flash keys & USB HDDs need the USB-A female connector (for the other end). Digicams & cellphones require mini-USB male or micro-B USB male.
Ideally, you'd get three different OTG cables, each with micro-A on one end and micro/mini/regular connector on the other end. Practically, you can't find micro-A to mini-B types (at least from a cursory search), and will have to settle for one cable + two adapters to fit all three USB sizes.
Lastly, note that the host device (Xoom) needs to provide sufficient power, if slave device isn't self-powered. In many cases with micro-USB, there isn't enough power, even if said slave device is a flash key or card reader. As above, it's hit-or-miss.
As obvious, confusion factor is high for all this micro/mini/A/B/male/female beeswax. I suspect this will be resolved once tablets become more common, and the simplest way to resolve it is to use full-sized USB ports. When you think about it, the micro- form factor is a holdover from the smartphone, as there's no rationale for it to be on tablets. Ironically, cheap shenzhen tabs for now are most likely to sport full USB ports.
In short, buy whatever cable you need for the Xoom. But for your next tablet (if you care about USB connectivity), buy one with full-sized USB ports. It will save a lot of headache.
Hmm, previous reply is a little confusing. To simplify,
There are 3 instances when you want to use Xoom in host mode:
1. Connect to USB flash key, (self-powered) USB HDD - Get one of these below
http://www.dealextreme.com/p/genuine-nokia-ca-157-micro-usb-otg-to-usb-data-cable-14cm-length-51045
http://search.digikey.com/scripts/DkSearch/dksus.dll?mpart=ZX40-A-5S-75-STDAJ
-or-
search eBay for USB OTG http://shop.ebay.com/i.html?_nkw=usb+otg
2. Connect to USB periph w/ mini-USB port: Get cable in #1, plus a mini-USB male to USB-A male adapter,
http://www.dealextreme.com/p/usb-male-to-mini-usb-male-adapter-32709
3. Connect to a USB periph w/ micro-USB port: Get cable in #1, plus a micro-B USB male to USB-A male adapter,
http://www.dealextreme.com/p/usb-to-micro-usb-adapter-58818
To provide external power-assist for un-powered devices, get a Y-cable,
http://www.amazon.com/Male-Power-Sync-Cable-Drives/dp/B002ZUV9IK/
The Xoom only takes Micro USB B, as far as I know.
You can see so by looking at the shape of the port:
I think if you got a Micro B to female normal A you wouldn't need all those other cables, as they would already come with the normal A male to what ever male they required and the host connection would be the right way.
Do I have that right?
Thanks for your input, I appreciate it.
>I think if you got a Micro B to female normal A you wouldn't need all those other cables, as they would already come with the normal A male
You can't use a normal micro-B cable, as it doesn't have OTG (pin 5 not grounded). The USB-A connector at the other end is irrelevant.
Given the Xoom can't take a micro-A connector, you'd have to find an OTG cable that uses the micro-B shell. I'd avoid using an adapter for reasons already mentioned. Since this has come up in this forum before, I'm sure solutions have already been found.
Via http://www.google.com/search?q=xoom+usb+otg+cable+site:xda-developers.com
and via http://forum.xda-developers.com/showthread.php?p=11997885
comes the apparent solution,
http://cgi.ebay.com/Micro-USB-Host-Cable-Nokia-N810-OTG-go-N-810-/250817547531
looks like the Nokia N810 OTG cable has the beveled micro-B connector. Credit goes to the OPs.
Awesome, thanks.
I bought that one from ebay that you suggested. It looks like the right one, in the picture it has a micro B male.
And they will even ship it here, for free. I'm amazed.
Will post results here. Thanks so much for your help.
Suggest also this cable if you're planning to hook up USB HDDs or digicams w/ mini-USB port. The Y-cable allows external power assist.
http://cgi.ebay.com/USB-2-0-Mini-5-Pin-Male-Data-Power-PC-HDD-Y-Cable-/130498137552
I'm confused.....
Will this fork for connecting a keyboard with my xoom when I get the update?
http://www.dealextreme.com/p/genuine-nokia-ca-157-micro-usb-otg-to-usb-data-cable-14cm-length-51045
And if not please please link me to one, as I have been looking forever but keep finding ****.
The eBay link you sent i can't see because I'm on my xoom and it just loads mobile.
Sent from my Xoom using XDA App
Work... not fork
Sent from my Xoom using XDA App
RadDudeTommy said:
I'm confused.....
Will this fork for connecting a keyboard with my xoom when I get the update?
http://www.dealextreme.com/p/genuine-nokia-ca-157-micro-usb-otg-to-usb-data-cable-14cm-length-51045
And if not please please link me to one, as I have been looking forever but keep finding ****.
The eBay link you sent i can't see because I'm on my xoom and it just loads mobile.
Sent from my Xoom using XDA App
Click to expand...
Click to collapse
No that won't work because that has a Micro A male and the Xoom only takes Micro B.
The ebay one is the one that works:
To view non-mobile, type in about:debug in the address bar and hit enter, it will look like nothing happened, then go to menu>settings>debug>UAString and change it from Android to Desktop. Then reopen the ebay link. It will reset to mobile every FC or when you restart your Xoom. But each time after you just need to type about:debug, it will remember the UAString setting.
But this is also a link to the same type of cable:
Meritline
Although they seem to be out of stock at the moment.
Hope this helps.
Tanks a lot
Sent from my Xoom using XDA App
I too connected my camera to the Xoom and it was recognized right away. I just wish it transferred the files automatically instead of manually. Anyway, I posted this link in another thread but in case it was missed, this is the Ebay seller I got my OTG cable from and it works for me:
http://cgi.ebay.com/Micro-USB-Host-...=260760886893&ps=63&clkid=9130826876118408283
e.mote said:
http://www.dealextreme.com/p/genuine-nokia-ca-157-micro-usb-otg-to-usb-data-cable-14cm-length-51045
Click to expand...
Click to collapse
Thanks for pointing to this cable! So now I ordered 2 even here in Poland we dont have much of "OTG" "Y" etc available ... at least they are hard to find.
Now I'm thinking on powering it.
I know we can use Y cable and powered usb hub.
But I'd like to have mobile solution.
I was thinking to pay someone (I dont have any tools and knowledge) to modify the nokia cable.
What do you think of buying a battery pack, that can output 5V / 500mA (I thing this is usb standard?) and connect it somehow directly to the nokia cable?
XOOM does not power the usb cable/ right? to there are 2 wires that should supply power, but they dont? What if we could just plug the power into them?
This is just an idea and I dont even know which wires to plug into
If anyone of You know what I'm talking about please comment on this... Thanks!
niematunikogo said:
Thanks for pointing to this cable!
Click to expand...
Click to collapse
That one won't fit into the Xoom.
You are going to have to try file the Micro A to fit into the Micro B port, as one of the other members of the forum has done, or get another cable.
Your cable end:
Micro USB A
The Xoom Micro B Port:
The difference between the 2:
Sorry man
Over in this post Cellzealot opined that I might be willing to share the pinout of the "factory cable" clone that I worked up. I absolutely am, but needed to find several hours of free time to do the writeup, images, etc.
The other night I set aside the time and did the writeup. If you would like to make your own cable, you can read the writeup here.
To oversimplify it, here is the map:
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
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The map is simple enough. The main problem (as detailed in the writeup I linked to above) is that since pin 4 is normally unused in a Mini/Micro B connector, there is no wire connected to it (to tie to), and in the case of the Mini B that I surgically dissected, the actual pin for pin 4 was nipped off at the back of the connector as well.
This doesn't preclude you from making a cable as you can always order brand new connectors and solder them up any way you like.
I'll be happy to answer any questions you might have in this topic.
great guide
Thanks for linking this to us! This would be tremendously useful to many on this forum. My question is, since the docks Motorola sells basically do the same thing, could the process be applied like callen81 did to make USB host functionality? It seems like the same process is used, albeit simpler.
Or just buy a USB 3.0 cable!
ya i picked up like three for like 1.50 each. monoprice.com has alot of cables for super cheap, good quality too
edit, i also got the 10 footers so i dont have to be bounded to the 4 footer that comes with it
Moved to proper forum.
Guys, a factory cable is not like the micro USB cables you buy, nor the standard "OTG" micro usb cables/adapters to become USB host.
Notice that PIN4 is tied to POWER, the +5V on PIN1, not to ground on PIN5 as in OTG cables (or left floating like on most mini/micro cables.)
This cable is essentially for being able to nvflash the phone, although perhaps it has other uses I am unaware of.
eval- said:
Guys, a factory cable is not like the micro USB cables you buy, nor the standard "OTG" micro usb cables/adapters to become USB host.
Notice that PIN4 is tied to POWER, the +5V on PIN1, not to ground on PIN5 as in OTG cables (or left floating like on most mini/micro cables.)
This cable is essentially for being able to nvflash the phone, although perhaps it has other uses I am unaware of.
Click to expand...
Click to collapse
It can also be used to charge the phone while flashing SBF.
Sent from my MB860 using XDA App
eval- said:
Guys, a factory cable is not like the micro USB cables you buy, nor the standard "OTG" micro usb cables/adapters to become USB host.
Notice that PIN4 is tied to POWER, the +5V on PIN1, not to ground on PIN5 as in OTG cables (or left floating like on most mini/micro cables.)
This cable is essentially for being able to nvflash the phone, although perhaps it has other uses I am unaware of.
Click to expand...
Click to collapse
isn't it also possible to use a usb keyboard with this method given that you have a usb powering hub in the middle?
The most useful thing to do at this point would be linking places that sell easily modified cables / adapters. As he said 99% of cables you find will not have the 5th wire connected or soldered on to the connector. Even if I had a cable or source of cables that had an easily solderable 5th pin this cable would be decently cheap to make. Most of the space cables I've hacked apart just have 4 solder points and a 'dummy' pin #4 (what, to look cool?) sigh.
bearsfan172 said:
It can also be used to charge the phone while flashing SBF.
Click to expand...
Click to collapse
I can't say for the Atrix, but for every other phone I've used the cable on, while it will power the phone while flashing, it will not charge the phone while flashing.
eval- said:
Guys, a factory cable is not like the micro USB cables you buy, nor the standard "OTG" micro usb cables/adapters to become USB host.
Notice that PIN4 is tied to POWER, the +5V on PIN1, not to ground on PIN5 as in OTG cables (or left floating like on most mini/micro cables.)
They do indeed have many uses
This cable is essentially for being able to nvflash the phone, although perhaps it has other uses I am unaware of.
Click to expand...
Click to collapse
They do indeed have many other uses besides the nvflash interface which is strictly for Tegra based devices. They not only power the device without battery, but autoload the Motorola networking driver and other interfaces for diagnostic mode NV access with both Motorola and Qualcomm service ware as well as flash tools like RSD Lite.
The device is always initialized properly and identified by the applications for various operations.
Similar powered cables have been used for all P2K generation Motorola devices for many years in various configurations. The real factory cables are made with a Mini USB B end and come with an adapter so they are compatible across a much wider range of older devices.
We hope very much that getting this info out will generate a lot of outflow for the many ways to apply the unique properties of these cables for newer devices.
In another topic Kholk had an idea that does away with the "missing pin 4 on the micro" problem. You can sacrifice a Motorola Mini-to-Micro USB adapter (SKN6252) which is wired for all 5 pins. This makes it a heck of a lot easier for the average Joe to make one and avoid the expense of buying a custom-made cable.
For most folks that would try this, that tip is all they need to proceed. If you want more detail, I did a step by step here.
If you make one up, post up and let me know how it went.
Enjoy!
MotoCache1 said:
In another topic Kholk had an idea that does away with the "missing pin 4 on the micro" problem. You can sacrifice a Motorola Mini-to-Micro USB adapter (SKN6252) which is wired for all 5 pins. This makes it a heck of a lot easier for the average Joe to make one and avoid the expense of buying a custom-made cable.
For most folks that would try this, that tip is all they need to proceed. If you want more detail, I did a step by step here.
If you make one up, post up and let me know how it went.
Enjoy!
Click to expand...
Click to collapse
I'm working on making my own, just to see if it'll work. I think it's going to turn out more frankenstein-y than yours, however.
PixoNova said:
I'm working on making my own, just to see if it'll work. I think it's going to turn out more frankenstein-y than yours, however.
Click to expand...
Click to collapse
Cool. I'd love to see it when you're done (if you wouldn't mind posting a pic). As long as you get the pinout right, it will work. Your attempt can't possibly be worse than my initial prototype was. If you have an SKN6252 lying around, you could actually make a pretty respectable looking cable.
Where can you buy one of these if your not good at soldering??
Make a friend who is good at soldering.
Does anyone know why Moto is allowed to call their connector USB when they don't comply to USB.ORG's standards and do things their own way?
cellzealot said:
They do indeed have many other uses besides the nvflash interface which is strictly for Tegra based devices. They not only power the device without battery, but autoload the Motorola networking driver and other interfaces for diagnostic mode NV access with both Motorola and Qualcomm service ware as well as flash tools like RSD Lite.
The device is always initialized properly and identified by the applications for various operations.
Similar powered cables have been used for all P2K generation Motorola devices for many years in various configurations. The real factory cables are made with a Mini USB B end and come with an adapter so they are compatible across a much wider range of older devices.
We hope very much that getting this info out will generate a lot of outflow for the many ways to apply the unique properties of these cables for newer devices.
Click to expand...
Click to collapse
Moto has been using nonstandard USB cables since they came out, many of which were dumb devices. The reasoning that they needed to be different so that they can do X Y or Z is bull. They want to lock you into Moto cables. No one has ever shown a logical reason for being different. You can flash phones with regular USB cables so the logic for a different format holds no validity.
Does this mean we could make one of these cables and have the phone "think" its either docked in the car or in the HD dock? I assume for the HD dock you might need added power but why cant I make a USB cable, plug it into my phone and hook up a USB hub to it like the dock?
not to hi-jack but it would be interesting to see if anyone has made their own docks, somehow the 3.5mm audio is integrated into the dock and is played through the usb cable...
Using the factory cable, Not insert the battery, display SVF: 105:1:2
Failed to boot 0x1000, infinite reboot
So I have been playing around with various USB game controllers as well as various storage devices and everything has worked so far (except BT, its detected but thats it). Hashcode has put a low priority on OTG in the kernal dev queue so I would like to get a discussion going about possible hardware solutions to over come the current 3.3v limitation of the USB port when running as a host (which is why devices dont work directly, only through a hub). Someone already suggested a current pump DC-DC in the kernal thread so my current focus something like this: http://www.circuitsathome.com/dc-dc/33v-to-5v-dc-dc-converter
for some motivation to this end, here is my USB NES controller hooked via OTG:
Controller use brought to you by HaiKaiDo Inc. lol
usb otg will work nice if we can up the voltage
usb otg will work nice if we can up the voltage from 3.7 to 5 volt
southbird already did a proof of concept with a voltage regulator from pololu
http://forum.xda-developers.com/showthread.php?p=25943787#post25943787
barrmulio said:
southbird already did a proof of concept with a voltage regulator from pololu
http://forum.xda-developers.com/showthread.php?p=25943787#post25943787
Click to expand...
Click to collapse
Yep saw that. My aim here is to go beyond that and come up with a real design
Sent from my Xperia X10 using xda premium
Can the voltage regulator be wired into the OTG cable? If so I am willing to try this but I need help with the wiring. I am searching now for some type of soapbox enclosure to house the voltage regulator. Any suggestions?
It would serve as the otg cable. The vreg will sit on the power rail between the kf and the normal usb connector. Ultimately, i want to lay out a smd board with the micro usb and regulator that goes in some little enclosure.
Basically what I am thinking of doing is putting the regulator inbetween the micro usb and female usb. It will look like other otg cables but the enclosure with the female usb will be larger.
I am assuming that the red(power) from micro usb is connected to the vout and the red(power) from female usb is connected to vin on the regulator. Do both sides of the ground need to be connected to the regulator or just to each other?
Can this work with GPS receiver?
sent from the greezals fire.
meturne2 said:
Basically what I am thinking of doing is putting the regulator inbetween the micro usb and female usb. It will look like other otg cables but the enclosure with the female usb will be larger.
I am assuming that the red(power) from micro usb is connected to the vout and the red(power) from female usb is connected to vin on the regulator. Do both sides of the ground need to be connected to the regulator or just to each other?
Click to expand...
Click to collapse
You could but IMHO, it would be simpler and cheaper to integrate everything as one device. The OTG cable is nothing special, just a micro USB B to regular USB A. The power needs to run from the micro in the KF to the vReg Vin, vReg Vout to the USB A connector, the ground is connected to all three.
greezal said:
Can this work with GPS receiver?
sent from the greezals fire.
Click to expand...
Click to collapse
No clue. I'm sure a google search would yield some answers
OK I'll look it up now and see if I can get the answer.
sent from the greezals fire.
greezal said:
OK I'll look it up now and see if I can get the answer.
sent from the greezals fire.
Click to expand...
Click to collapse
Just looked it up and not much on the subject have not got a straight answer. Would be great though.
sent from the greezals fire.
Ok, the ones I ordered are in. Size is NICE, it should be really easy to integrate this into existing USB connector enclosures. This is the 120 mA version, the 600 mA version is about twice the size
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altitude909 said:
Ok, the ones I ordered are in. Size is NICE, it should be really easy to integrate this into existing USB connector enclosures. This is the 120 mA version, the 600 mA version is about twice the size
Click to expand...
Click to collapse
very nice - i ordered the pololu one and still waiting for it to arrive
my thoughts were similar; integrate the regulator into the usb female header area of the otg, or somewhere mid-cable...but I'm having a hard time finding an elegant solution to either re-enclosing the plastic end of the female header or enclosing it mid cable
i just back another otg cable today, i'll be cutting it apart to see if there's enough space by the usb a
success! kinda.. For super low current devices (i.e. NES game controller) it is working fine, anything larger (flash memory) its drawing too much current causing the voltage to sag below 2.5V which is not enough to power the regulator. Will try the LTC3426 one tomorrow since that should be able to operate at a lower input voltage
altitude909 said:
success! kinda.. For super low current devices (i.e. NES game controller) it is working fine, anything larger (flash memory) its drawing too much current causing the voltage to sag below 2.5V which is not enough to power the regulator. Will try the LTC3426 one tomorrow since that should be able to operate at a lower input voltage
Click to expand...
Click to collapse
just to make sure I got your wiring right
from micro usb b
- red to vReg Vin
- pin 4 to ground
- pin 5 to ground
from usb a
- red to vReg Vout
- black/pin 4 to ground
?
my stupid otg cable doesn't have standard colors (it's green, blue, yellow, red, yellow&red), so other than vcc i'm not sure what's what (edit: now i think blue is gnd and yellow/red is sense, yellow is d-, green is d+).
I was also expecting the otg short to be on the micro side and not on the usb a side, but it wasn't
my idea is to have the regulator sit inside the hollowed out area of the female header seen on the bottom left
Just take a meter and see what is connected to what. It does not matter where pin 4 and 5 are shorted.
Unfortunately, it looks like without some sort of magic, the port on the kf cannot supply enough current to drive these regulators. Im observing the same thing as southbird did, the devices show up but do not work. Measuring the voltages at the power pins with a flash drive connected i get 2.4v at the vreg input and 4.5 at the output which means that there is too much load. Time to start looking for battery powered usb hubs
this battery charger or this usb charger both work well for me with a y usb cable...i've seen some other posts with folks that just wired right into the charger, e.g. here
ok, the regulator arrived today and i played around with it
the otg cable was too frail for my poor soldering skills to do properly, so i ended up cutting up a usb extension cable to about 1' in length and soldering it halfway...i'll enclosure in heat shrink later
my results were pretty much the same as southbird and altitude909
My 8Gb centon usb however mounts perfectly *every* time, however my 4Gb, 2Gb or 512Mb sticks will not mount. When I try the elago w/ a 32Gb micro it conks out mounting as a whole, requiring a reboot of the KF to remount the 8Gb stick (probably some kernel protection)
so you need a regulator to get flash drives to work? that explains why it never worked for me lol
Hi,
I had a new case and keyboard arrive for my nexus today but the keyboard doesn't seem to be detecting at all. I've been browsing all evening trying to find a fix but to no avail so far...
These are the specifics;
Nexus 7 wifi 32gb stock rom, JB 4.2.1
This exact MINI USB Keyboard (Can't identify manufacturer as the keyboard is built in to the case)
Mini usb - micro usb connector
I have verified the usb connector is working fine as I am able to plug in a mini usb charger to the nexus through it and it charges fine.
When I plug in the keyboard it doesn't work or seem to be detected in any way.
Where am I going wrong?
I can't try a USB OTG cable as I am not connecting a full size USB peripheral. I installed usb host diagnostics and ran it with the keyboard connected but I'm not sure how to interpret the results which are as follows;
{
"lightbox_close": "Close",
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"lightbox_error": "The requested content cannot be loaded. Please try again later.",
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"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
"lightbox_toggle_sidebar": "Toggle sidebar"
}
Additional info;
I added a 51-android.rules file as per the process in this thread, and included ALL manufacturers and ID codes but still no fix
You *do* need an OTG cable. It has two pins (4 and 5) connected. That's what tells the tablet that it's in host mode. If you want to adapt yours, here's the procedure (obviously, use at your own risk!):
http://forums.androidcentral.com/go...iy-making-your-own-otg-cable-image-heavy.html
tjupille is correct, a normal micro USB cable will only have 4 pins connected, the 5th pin needs to be grounded on the tablet side of the cable. If you can find/make a such a cable and if it's a standard USB HID keyboard then it should work out of the box on a stock N7 without the need for any special configuration.
I have also seen where some non-stock ROMs lose the OTG support. This wouldn't be your case as you are running what looks to be a stock ROM. Now then, I have had a few OTG cables go bad. Some of them are just made cheaply.
Thanks all, I understand the otg cable setup much better now. I figured that with a standard connection android should see the device as an input device and it would just work. Have a cable on order now. I have the kit to mod my existing adapter but for such a small amount of money I'd rather not gamble frying my nexus. Look forward to when it arrives as I keep going to use the hard keys!
Sent from my Nexus 7 using xda app-developers app
ixampu OCEANSIDE-3
dealextreme has some otg cables, you can purchase it.
A # of eBay stores carry these Micro USB Host Mode OTG Cable, originally designed for the Samsung Galaxry devices - I got one as a bundle along with the swivel case & screen protector, etc. Inexpensive & it works - on 4.1.2 and on 4.2.1 depending on the rom & kernel.
One of them selling a pair for under $5, free shipping and they are based in the LAX area of CA, mine arrived in less than a week - vendor has been around for years and sourced them mostly from oversea. The short piece of connecting cable is a bit longer than picture but still fit flat & tight against the bottom/side of the N7 with the case, so it won't be too bad flying 6 or 10+ hours with my own huge library collection of DVD's on a stick. Not a vendor / product endorsement & plenty of sources to get yours, plus Amazon ...
http://www.ebay.com/itm/2x-Micro-US...338153?pt=PDA_Accessories&hash=item56517d1069
Mine was quite difficult to find as it's a micro one end and mini the other, but I've located one and it's ordered. Thanks for the links guys. I'm in the uk, it seems to be particularly difficult to find the one I need here for some reason!
Just my $0.02 on the whole OTG thing though.... why can't it be that simple to just connect a usb device and for it to work like things used to?? Why the need for an adapter? Surely these keyboard cases should all be OTG wired for maximum compatibility as a keyboard is never going to be a host device!
Ho hum...
Then if i understand good i need otg cable to be able to connect my keyboard ! The problem is my keyboard is already micro usb and i just find
OTG micro usb to usb 2.0 .
How to do then ?
Well I'm glad I found this thread after a couple of hours of fruitless searching (& mostly getting stuff about flash drives).
I tried to connect a case logic mini usb keyboard which I acquired for the princely sum of ten bucks, by using the cable that shipped with the Nexus and a usb gender changer, but the tablet did not recognize the device. I've had no trouble hooking the tablet up to a pc for chrome debugging, file xfers etc, and I tested the mini kb on a couple of pcs.
I thought it was something like this OTG adaptor thing, but couldn't figure out what was special about it vs. bog-standard usb plugs. I ordered one along with a powered usb hub, in case that was the/another issue, and look forward to getting this thing to work.
Thanks!
Edit: Sweet! The OTG adaptor worked like a charm, and with a powered hub I can run a wireless mini-mouse too.
Hi guys, I know this thread is quite old, but I have very, very important problem:
I've recently bought the same built-in to case keyboard with two wires: micro and mini.
The problem is that the micro one connected to the Nook Tablet or HTC Sensation does not work (although in case of HTC Sensation it is detected!).
When I connect the same keyboard to my sister's no-name tablet (something-made-in-China) via miniUSB it works like a charm! With no adapters, nothing!
The question is: should I try to find OTG adapter (and if yes, then which one? miniUSB to microUSB, or rather microUSB to microUSB?) ?
Thanks in advance for all your replies...
Waszker said:
Hi guys, I know this thread is quite old, but I have very, very important problem:
I've recently bought the same built-in to case keyboard with two wires: micro and mini.
The problem is that the micro one connected to the Nook Tablet or HTC Sensation does not work (although in case of HTC Sensation it is detected!).
When I connect the same keyboard to my sister's no-name tablet (something-made-in-China) via miniUSB it works like a charm! With no adapters, nothing!
The question is: should I try to find OTG adapter (and if yes, then which one? miniUSB to microUSB, or rather microUSB to microUSB?) ?
Thanks in advance for all your replies...
Click to expand...
Click to collapse
OTG for the nexus 7 is a bit different in terms of hardware requirements. Pins 4 and 5 on the micro USB side have to be shorted together for it to work. You will likely need an OTG cable that says in the description that it is compatible with the Nexus 7. Amazon and eBay are decent places to go.
Sent from my Nexus 7 using xda premium
Hey, I bought the same keyboard, foolishly.
Is buying another cable the only way to get to work?