USB hubs not recognised

[Billericay Pete]

I have 2 powered USB 2 hubs connected to my vista PC - neither are
recognised - i.e. if i plug my printer/mp4 player/camera etc into the hubs
my Pc does not realise they're there. There are 2 ports on the front of the
PC and 3 at the back - it makes no difference where I plug the hubs in, they
are not recognised.
If i plug my printer/mp4 player/camera etc directly into 1 of the USB ports
on the PC they are recognised.

Any ideas?
Many thanks in advance
Pete

 

[R. McCarty]

Likely a USB Root Hub power overload ( ~500mA Limit ). USB is
internally routed based on the USB technology detected. Most PC's
have a single Enhanced ( USB 2.0 ) controller/root hub. If detected
as USB 1(.1) then it routes to a Standard Controller/Hub. The OS is
supposed to report an overcurrent condition but many times devices
will simply not be detected. It's important to know what each device
draws in the way of Root Hub current.

 

[the wharf rat]

I have 2 powered USB 2 hubs connected to my vista PC - neither are
recognised Any ideas?

Ummmm, don't plug them into the hubs?

Seriously, USB stands for Unstable Serial Bus. It's not unusual
to have the port something's plugged into matter, especially when you
add hubs to the chain.

You can play around with different hubs, different USB drivers,
and so on, and it might actually work or it might not. C'est le silicon.

 

[Billericay Pete]

Thanks for your reply
I can understand that it's a possibility - but nothing works in them - they
worked fine on my old Dell PC - I've just bought a new quad core Mesh with
all the extras (the spec says it has 6 x USB 2.0 ports) so I'd expect just 1
thing to work via the hub, but not even my Bluetooth receiver let alone my
camera/printer/mp4 player wont work with even just 1 of them plugged in -
surely some single thing should work via one of the hubs?

Thanks again
Pete

 

[R. McCarty]

Are the hubs externally powered, or do they receive power via the
actual USB bus ? & are the hubs USB 2.0 or 1(.1) >?
It is unusual that no devices get picked up by connecting via the hub.
I'd connect a hub and then go through Device Manager, USB, Root
Hubs one at a time and check the Power (TAB). See if the expansion
Hub is detected on one of the internal hubs.

 

[the wharf rat]

camera/printer/mp4 player wont work with even just 1 of them plugged in -
surely some single thing should work via one of the hubs?

This actually happened to me on a machine once. In the BIOS
there was a setting called something like "USB reference voltage" with
three options, low, med, and high. Until I set it to high the only things
that worked on that port were USB flash drives.

 

[Billericay Pete]

Thanks again..
The hubs are both USB 2.0 hubs and both are powered.

The power tab indicates - USB Root hub 1
The hub is self-powered
Total power available: 500mA per Port
eHome Infrared receiver (USBCIR) 100mA
Generic USB Hub (3 ports) 400mA
6 ports available

The power tab indicates - USB Root hub 2
The hub is self-powered
Total power available: 500mA per Port
USB mass storage Device 0mA
USB mass storage device 250mA
6 ports available

Is that good, bad or indefferent??
Thanks again
Pete

 

[Billericay Pete]

Thanks - I checked the BIOS and the only thing relating to USB was to
enable/disable.....
hey ho
Cheers
Pete

 

[Billericay Pete]

Thanks - I checked, the BIOS indicates they're all enabled.
Each device works fine if i plug it directly into a port on the PC - just
doesn't work when plugged into any of the ports on either of the USB 2.0
self-powered hubs.
As there are only 2 ports on the top of the PC (1 of them has my bluetooth
receiver for mouse/kbd) i have to keep switching them around - very
frustrating!
The other 4 ports are at the back of the PC and not easily get-attable....

Thanks
Pete

 

[R. McCarty]

Looks fine, no potential overloads. The "Generic USB Hub" is the
normal identification string for expansion hubs. You might try to add
a device to a expansion hub and re-examine the Root Hub to see if
still shows the same number of available ports or the device itself is
shown in the power tab.

 

[Karl Snooks]

When you say "self-powered", does this mean that they are powered from a
separate power supply and NOT from the computer. You need hubs that have
their own power source which plugs into a wall-outle, the mains or whatever
you call it, but NOT using power via pins 2 and 3 of the USB cable connected
to your computer.
karl

 

[Billericay Pete]

Thanks Karl - yes they each have their own mains driven power supply.
Cheers
Pete