Disable USB ports - free up IRQ´s

  • Thread starter Thread starter FVe
  • Start date Start date
F

FVe

Hi all,

I´m still trying to get my system running good and the stand-by option
working.

I notice, when I disable most USB-ports, that it works fine (less IRQ´s
needed). Therefor I´m thinking about an external USB2.0 hub to compensate
the loss of the onboard ports.

In device manager, I see a lot of USB-devices:
1 ASUSTEC Enhanced Host Controller
1 Intel 82801BA/BAM USB universal Host Controller 2442
1 Intel 82801BA/BAM USB universal Host Controller 2444
2 Open host-controller USB NEC
4 USB root hub.

The headers I have on the back of the machine:
2 USB1.1
4 USB2.0

I noticed that when I disable all the USB devices except:
1 open host controller USB NEC and
1 USB root hub,
that only one USB port (supposed to be a USB2.0 header) is still
functional - this one I could connect a hub to.

But is it a USB2.0 connection then? Even without the 2442/2444 drivers
loaded? How do I know?
(I would like to know, to prevent buying another unneeded device)

The BIOS-settings won´t help, because there is only the option "both" or
"disable" ;(

Regards,
Frank
 
What type of motherboard is this?
Seems to have too many USB controllers listed for only 6 ports.....
AFAIK the Enhanced host controller is the USB2.0 controller. If this is not
visible in device manager, you will only have USB 1.1 available.
Are all the ports onboard?.. or is there a USB 2.0 PCI card installed?
For my Intel ICH4 which has 6 USB2.0 ports, there is 1 Enhanced controller,
3 Universal controllers, 1 USB 2.0 root hub, and 3 USB root hubs.

John S.
 
"Muttley" <[email protected]> schreef in bericht

Hi! thanks for your help so far!
What type of motherboard is this?
Click to expand...

Duh! Forgot to mention a small detail ;((

It´s a P4B266E
Seems to have too many USB controllers listed for only 6 ports.....
Click to expand...

I agree, but is there a trick to minimize the amount of used controllers?
AFAIK the Enhanced host controller is the USB2.0 controller. If this is not
visible in device manager, you will only have USB 1.1 available.
Click to expand...

This is what I was afraid of.....
The USB2.0 header will work even without the Asustec Enhanced controller.
Does it work then as a 1.1 controller without the enhanced controller
enabled instead of a 2.0?
Are all the ports onboard?.. or is there a USB 2.0 PCI card installed?
Click to expand...

No,
4 of the headers are straight onboard USB connectors (2x 1.1 and 2x 2.0),
2 of them are connected as "front headers".
For my Intel ICH4 which has 6 USB2.0 ports, there is 1 Enhanced controller,
3 Universal controllers, 1 USB 2.0 root hub, and 3 USB root hubs.
Click to expand...

Hmmm...this is also strange? 3 controllers for 4 hubs?
Does it take 4 IRQ´s in your system (or at least mentioned 4 times in the
IRQ list?)

btw: the chip in my machine is the 82801BA (ICH2) chip.

Frank
 
"Muttley" <[email protected]> schreef in bericht

Hi! thanks for your help so far!
What type of motherboard is this?
Click to expand...

Duh! Forgot to mention a small detail ;((

It´s a P4B266E
Seems to have too many USB controllers listed for only 6 ports.....
Click to expand...

I agree, but is there a trick to minimize the amount of used controllers?
AFAIK the Enhanced host controller is the USB2.0 controller. If this is not
visible in device manager, you will only have USB 1.1 available.
Click to expand...

This is what I was afraid of.....
The USB2.0 header will work even without the Asustec Enhanced controller.
Does it work then as a 1.1 controller without the enhanced controller
enabled instead of a 2.0?
Are all the ports onboard?.. or is there a USB 2.0 PCI card installed?
Click to expand...

No,
4 of the headers are straight onboard USB connectors (2x 1.1 and 2x 2.0),
2 of them are connected as "front headers".
For my Intel ICH4 which has 6 USB2.0 ports, there is 1 Enhanced controller,
3 Universal controllers, 1 USB 2.0 root hub, and 3 USB root hubs.
Click to expand...

Hmmm...this is also strange? 3 controllers for 4 hubs?
Does it take 4 IRQ´s in your system (or at least mentioned 4 times in the
IRQ list?)

btw: the chip in my machine is the 82801BA (ICH2) chip.

Frank
 
Hi,

Your board has a USB1.1 interface in the ICH2 chip that controls the four
USB1.1 ports via the two Intel 82801 (2442/2444)controllers. These account
for two of the USB root hubs. Two ports are available on the backplane and
the other two are available via an onboard header. As far I can can work out
these controllers are both enabled/disabled by the BIOS setting.

The USB 2.0 capability is provided by an extra USB2.0 controller chip (NEC?)
on the board that is enabled/disabled by a jumper on the board. The four USB
2.0 ports are controlled by the single Enhanced host controller when running
in USB2.0 mode. If a USB 1.1 device is connected to a USB2.0 port, one of
the NEC Open Host controllers is used to run it. The open host controllers
account for two more USB root hubs. There should also be an Enhanced/USB2.0
root hub in the device listing as well. Depending upon what speed USB device
is connected to one of the USB2.0 ports, the USB2.0 chip connects the
appropriate mode controller to that port. The four ports are provided the
same way as the USB1.1. ie two ports on the backplane, and the other two
useable via an onboard header.

Now to IRQ assignments. Each USB controller requires 1 IRQ. Your board has
five USB controllers on it, so five IRQ asssignments will be required to use
all ports.

AFAIK, your only options to minimise controllers, is to disable either the
onboard USB1.1 controller(BIOS), or the extra USB2.0 controller(Jumper).
Disabling the chipset controller will remove the two intel controllers, and
free up two IRQ assignments. Disabling the extra USB 2.0 chip will remove
the Enhanced contoller and the two open host controllers, and free up three
IRQ assignments. AFAIK, the USB 2.0 ports will not function at all if the
Enhanced controller is disabled in device manager, but if they still work
with the Enhanced controller disabled, they will only be in USB1.1 mode.

Re my ICH4 IRQs:
Four IRQ assignments are used on my board. Three for the USB1.1 controllers
and one for the Enhanced USB2.0 controller. The board actually has four USB
root hubs - One USB2.0 root hub and three standard root hubs.

John S.
 
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