Can someone explain USB to me?

Every time I plug in a usb device (windows) tells me it would work faster with usb 2.0. I have a cheapie white box, so I’m not surprised I have usb 1.1 inside. I saw a REAL cheapie pci card that would give me usb 2.0 and I ordered it. When I got it, the instructions said “No driver - plug n play.”

Then, in print so tiny I can barely read it with a magnifying glass, the instructions said something about the card not working if you have other usb things plugged in and it listed 3 connections? ports? something. Well, I plugged the card in and usb stopped working. So, I unplugged all devices and re-plugged only to the new card. One of my goals was to have unlimited usb ports. That ain’t happening. While I had the box open, I tried to see a way to disconnect the old ports on the back of the box but could see no way to do it. The connector is in some kind of little metal enclosure.

I do have 2 non-working usb ports on the front of the box. I figured I might as well pull their plug since they don’t work anyway and they might be causing a conflict. I looked at the wire to the front usb, turned my head, and pulled the wrong set of wires off. Now, my computer won’t start. In a panic, I tried to imagine how killing the usb would kill my pc. Then I noticed that I had pulled the connection to the front power switch and an led. I put them back together and still no power. Now in full panic mode, I discover one of the tiny wires is labeled reset, as is the tiny connector on the mobo. I pressed the reset button, instead of the power button, on the front of the case. That button had never worked before. Now that I am back in business, I figure, why leave well enough alone? 20 minutes later, I have my correct buttons back AND the front usb ports are working for the first time since I owned the box.

So, that is the first question: Why can’t I connect all these usb ports and why are the front and pci card ports now working.

Second question: lsusb shows the first two entries as 2.0 hubs. I now have 7 usb bus devices. No matter where I plug a device in, it is never associated with one of the 2.0 hubs but rather with one of the remaining 1.1 hubs. What’s going on?

Also, are the usb devices assigned on the fly? If I plug a device in, unplug it and replug it, where it connects seems random. Isn’t the physical port always the same address? Can these be fixed (permanent) if I want a usb backup hard drive or a webcam to always be on a 2.0 hub but not continuously plugged in?

Probably your computer is old enough that the BIOS only supports USB 1.1 version. If the added USB card doesn’t have its own BIOS you would need a software driver for it which would have to come from the cards manufacturer. You might also need to change the computers BIOS to disable the onboard (rear panel) USB connectors. You don’t give any information about the “real cheapie pci card” so we can’t help you with it.

Tom

Universal Serial Bus - Wikipedia, the free encyclopedia might help.

  1. What is PC specs? 2) What is the Windows OS in use? 3) This is a Linux forum, we will try to help some, but do you have Linux preferably openSUSE installed? The PC Specs will govern whether you may be able to flash the BIOS to enable USB 2.0 or whether you will need a third party driver. The windows OS will govern whether it can handle USB, USB1.1, or USB2.0 natively or whether it needs third party drivers. And if you have Linux, this may offer more work arounds for your circumstnce.

Then, in print so tiny I can barely read it with a magnifying glass, the instructions said something about the card not working if you have other usb things plugged in and it listed 3 connections? ports? something. Well, I plugged the card in and usb stopped working. So, I unplugged all devices and re-plugged only to the new card. One of my goals was to have unlimited usb ports. That ain’t happening. While I had the box open, I tried to see a way to disconnect the old ports on the back of the box but could see no way to do it. The connector is in some kind of little metal enclosure.

We will need to know exactly what the micro print says, who made the USB card? What card model? The rear panel USB ports and directly wired and must be shut off in the BIOS.

I do have 2 non-working usb ports on the front of the box. I figured I might as well pull their plug since they don’t work anyway and they might be causing a conflict. I looked at the wire to the front usb, turned my head, and pulled the wrong set of wires off. Now, my computer won’t start. In a panic, I tried to imagine how killing the usb would kill my pc. Then I noticed that I had pulled the connection to the front power switch and an led. I put them back together and still no power. Now in full panic mode, I discover one of the tiny wires is labeled reset, as is the tiny connector on the mobo. I pressed the reset button, instead of the power button, on the front of the case. That button had never worked before. Now that I am back in business, I figure, why leave well enough alone? 20 minutes later, I have my correct buttons back AND the front usb ports are working for the first time since I owned the box.

Ah! so Front side panel was wired wrong all this time, well there goes my explaining how to fix a badly wired MBO.

So, that is the first question: Why can’t I connect all these usb ports and why are the front and pci card ports now working.

Second question: lsusb shows the first two entries as 2.0 hubs. I now have 7 usb bus devices. No matter where I plug a device in, it is never associated with one of the 2.0 hubs but rather with one of the remaining 1.1 hubs. What’s going on?

Front USB are working because who ever plugged the wires into MBO originally, did it wrong and you have fluked into wiring it right. Being that you are using the lsusb command I take it you are using Linux, so how about posting the results of lsusb to give us something to work with. My crystal ball is telling me you have 3 usb1.1 on backplain of MBO, 2 usb1.1 on front, 2 usb2.0 on pci card. You will only get usb2.0 if the device plugged in supports usb2.0 AND the usb connection is a usb2.0 (on the pci-card).

Also, are the usb devices assigned on the fly? If I plug a device in, unplug it and replug it, where it connects seems random. Isn’t the physical port always the same address? Can these be fixed (permanent) if I want a usb backup hard drive or a webcam to always be on a 2.0 hub but not continuously plugged in?

USB are assigned on the fly to the appropriate hub, the hub used may be random, since usb is talked to by device id, it does not matter where is gets assigned. The hub controller is on a physical address, then each hub ties in parallel. Again, if the device supports usb2.0 and it is plugged into the usb2.0 connector on the pci-card, the system will handle it properly otherwise, the system will fall back to usb1.1. Nothing can be done IMHO to force it to a specific load point.

On 2010-09-18 00:06, Prexy wrote:
>
> Every time I plug in a usb device (windows) tells me it would work
> faster with usb 2.0. I have a cheapie white box, so I’m not surprised I
> have usb 1.1 inside. I saw a REAL cheapie pci card that would give me
> usb 2.0 and I ordered it. When I got it, the instructions said “No
> driver - plug n play.”
>
> Then, in print so tiny I can barely read it with a magnifying glass,
> the instructions said something about the card not working if you have
> other usb things plugged in and it listed 3 connections? ports?

I have an old computer (circa 1995 make, pentium I) with only usb 1.x. I added a card with four usb
2.x connectors - all work, old and new. I use the old connectors for slow things, and the new for
fast things. At least in Linux, I don’t remember about the old windows in that box.

I could look up its make.

> Also, are the usb devices assigned on the fly?

Yes, I think so.

Of course, they will be on the usb 2 bus or the usb 1 depending on what connector you plug to, they
are really different chips and hardware.


Cheers / Saludos,

Carlos E. R.
(from 11.2 x86_64 “Emerald” GM (Elessar))

Ok. For those that delight in data: more data!
The mobo is Intel D845PESV.
The usb card is NEC D720101 PCI to USB 2.0
lsusb gives me:

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 002: ID 058f:9254 Alcor Micro Corp. Hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 007 Device 002: ID 08bb:2900 Texas Instruments Japan PCM2900 Audio Codec
Bus 007 Device 003: ID 051d:0002 American Power Conversion Uninterruptible Power Supply

The audio codec thing is a turntable (if you’re too young to know what that is, just forget about it.)
Other pertinent data:

Linux 2.6.34.7-0.2-default i686
System: openSUSE 11.3 (i586)
KDE: 4.5.1 (KDE 4.5.1) “release 296”

I brought up the windows stuff only to point out that I get messages that usb 2.0 would be faster. It doesn’t enter into this problem in that windows is about 2% of my computing time.

This card has 4 external ports and there is one internal that appears to be a regular usb connector. At one point I thought I could run some kind of patch cable internally to get one set of the built-in ports up to usb 2.0, but I guess not. Right now I have just a couple of uses for the faster connection: a backup hd; a webcam and maybe that turntable thingy.

One other question: does a hub connected to a 2.0 have to be special or will any old hub do (such as that hub at Bus 004 Device 002)? How about a cable that acts only as an extension cord?

Ok, that card has 4 USB2.0/1.0 compliant ports for external use, and one usb 2.0 internal port sharing the bus with the first external one. The intension of the internal port is for wiring to a front panel usb connection. Connecting it to the MBO’s internal buss connection will damage the usb controller on the MBO! USB is provided via the internal pci card slot connection which attaches the internal Via chip set USB controller to the main system board. This fact is backed up by the fact that you have Buss 001 & 002 as USB2.0 hubs.

Can I run an A-A usb cable (in essence, an extension cord) from that internal connector through an opening in the back and use it as an ordinary usb port?

Yes. It is a regular port, the only reason it is inside the case is so that it can service the front panel should the front panel have USB connectors and the motherboard doesn’t. so any USB A-A, A-B Cable can work, just be sure if passing it through the case not to pinch it with sharp metal that can harm the cable. A grommet comes to mind.

Thanks. I’m sure I have extra cables from something or other that will give me the extra port.

What about the issue of getting a 2.0 connection to a specific device?

On 2010-09-20 17:36, Prexy wrote:
>
> Can I run an A-A usb cable (in essence, an extension cord) from that
> internal connector through an opening in the back and use it as an
> ordinary usb port?

In my card, that internal connector is wired directly to one of the external connectors. I can use
one or the other, not both.


Cheers / Saludos,

Carlos E. R.
(from 11.2 x86_64 “Emerald” GM (Elessar))

True you have to use only one or the other. However, use a 2 port, 4 port, 8 port or 12 port external hub on a connection and you can easily handle many devices on each of the ports. Example: I have a 2 Port USB 2 on one of my machines, I added a pci USB card with 2 external ports and 1 internal port (tied physically to one of the external USB ports). My internal connect I connected to a previously unused front panel port. To this front panel port I attached a 4 port mini hub which gives me 4 ports on the back of the machine (two on MBO,two on PCI card) and 4 ports on the front via the hub. Now one might think this adds up eight but in fact one of PCI back panel ports becomes unusable when the 4 port hub at the front is in use.

You’re saying you lose only one back panel port? Is it predictable? repeatable? That is, will it always be the same physical connector? I haven’t stressed the system since I started this thread, but if my 7 ports are all available, that’s plenty… except, I want to be able to always be able to know where to connect 2.0 devices.

Just do as I did, go to the manufacturers site and read the specs. It says, the first USB port on the backplain ties directly to the inside port such that you may have the second backplain port steady and a choice of either the first backplain port or the internal port depending on what is plugged in. USB assignment is pretty predictable. attach or USB 2.0 device to port 2 of backplain and if you have a second USB 2.0 device plug it into either the first backplain port or the internal and just know that if you are using the internal, the first backplain port must not be used and visa versa.

Thanks. I’ll set things up this way.:slight_smile: