Hello Paul,
I found some time to continue the discussion.
Am Fri, 28 Nov 2008 10:27:32 -0500 schrieb Paul:
> Klaus Haber wrote:
>> Hello,
>>
>> I use the ASUS-Board P5GD2 Deluxe. This board has totaly 8 USB 2.0-ports, 4
>> at the real panel direct connected and 4 ports at the front, connected by
>> cable to the board.
>>
>> I found out, that 2 ports at the front will not work properly, if I connect
>> them to my Epson Scanner. If I do so, I get a failure message, that an
>> other scanner is already connected to the computer, which is not true. All
>> other 6 USB-ports are working well with the scanner. I changed the
>> USB-cable, no success. If I connect a camera, an USB-stick, an external
>> USB-harddisk to these both ports, they all work well, exception is the
>> scanner. I have no idea, what could be reason of this effect. Have the
>> different USB-ports also differnt valances?
>> If I connect the scanner to the different ports of my laptop, also no
>> problems. So I assume, that the failure should be at the ASUS-board.
>>
>> Is there one possibility to test generally an USB-port for its
>> functionallity?
>>
>> Thank you for comments, regards
>>
>> Klaus Haber
>>
>
> You have one of these in the motherboard box.
>
> http://estore.asus.com/images/14-000012222.JPG
Correct, I have this adapter (missing the game plug).
>
> Disconnect the front panel USB wiring. Connect up the
> 2x5 USB cable of the 14-000012222 adapter. (You don't
> need to connect the game port.)
>
> Plug the scanner into the faceplate of the adapter.
> Test the scanner. If it works with the Asus adapter,
> but not with the computer wiring, then the computer
> wiring is faulty.
>
Maybe I didn't report exactly enough.
This adapter was installed due to the handbook of the motherboard since I
got the computer. I used this adapter all the time with success for all
commen hardware. Only the scanner was connected from the beginning to the
rear USB-port. The reason was the local arrangement of the scanner at the
table.
Some month ago I rearranged the local hardware and the scanner moved to a
place, from which it was easier to plug the USB-cable into the adapter at
the frontside than to the real. And since this rearrangement I got the
malfunction of the scanner. Therefor I don't believe, that the malfunction
is due to a failure in wiring or thomething else. If I connect the scanner
back to the realport, it is running well again. If I connect other
consumers (cameras, sticks, harddisks a.s.o.) to the same frontadapter,
they are also running well. That would demonstrate, that the wiring is ok.
An other point. As far as I know, there are two classes of USB-ports. I
don't mean the 1.x resp. 2.0 clas but the class of powersupply. One class
has a powercapacity of ~ 200 mA ( I don't know the exact value) and the
other class of ~ 500 mA (not the exact value). The first class is used by
hardware with low powerconsumption, the second one for high
powerconsumption. USB-hardware with high power will not run proper, if they
are connected to the lowpower USB-port. I took a look at ASUS Homepage, but
I did not found any information about the class of my ports at the
motherboard. My scanner has an own powersupply, so it should not be
necessary to use a lowpower-port.
At the other hand, the scanner will run at all 3 USB-ports at the laptop.
Grrrrrrrrrrrrrrrr, I don't understand this ;-)
@Rob
I studied your link exactly and I found nothing which did not meet my
wiring. From this point of view, every thing is wired right.
Can you (both) give some comments to the powersupply-classes of the
USB-ports in connection with the plugged consumers?
Regards
Klaus
--
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