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noup
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 Posted: Thu Apr 14, 2005 9:30 am Post subject: [unsolved] Using an usb hub as a non-hub |
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This may sound strange, so let me try to explain. My Apple display has a 2-port usb 2.0 hub. However, we all know how "far" usb hubs can go, so there are some devices that don't work when connected to hubs, like my USB Bluetooth dongle, for example. But still, having an usb port available on the display is quite useful, since it's much easier to connect devices there than it is on the back of the computer case.
So, is there any way that i can use one of the display's usb ports as a simple usb extension, instead of treating the ports as a hub? This way my devices would work, because they would then be connected to a normal usb port, and not an usb hub port.
I'm not searching for a solution that involves hardware modification, but rather an answer to the question of this being possible with software or not (perhaps with some drivers change, i don't know).
Thanks in advance for anyone trying to help figure this out. 
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Last edited by noup on Sun Apr 17, 2005 9:26 pm; edited 1 time in total |
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NeddySeagoon
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| Posted: Thu Apr 14, 2005 1:43 pm Post subject: |
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noup,
Its not possible. A USB hub is a piece of dumb electronics. There are no drivers for it.
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noup
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| Posted: Thu Apr 14, 2005 2:00 pm Post subject: |
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| NeddySeagoon wrote: | noup,
Its not possible. A USB hub is a piece of dumb electronics. There are no drivers for it. |
That's quite the answer i was expecting... but there must be something (this is me with some hope left) more than "dumb electronics" in it, or else, how would it know for which device to send a "packet" it has just received, for example? doesn't it contain some kind of changeable firmware? :/
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NeddySeagoon
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| Posted: Thu Apr 14, 2005 2:39 pm Post subject: |
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noup,
I don't have a USB hub to play with just now but I think it sends all packets everywhere, rather like a Ethernet hub.
Its up to the devices on the end to determine if a particular packet is for them.
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TerranAce007
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| Posted: Thu Apr 14, 2005 2:45 pm Post subject: |
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Is the hub powered or not? When you connect peripherals via USB, some draw their power from the USB port and some use external power. For example, my wireless USB mouse and my joystick both draw power from the USB port, so the hub has to have enough power for them, and this comes from an AC adapter. Other things, such as my printer, already use AC power from the wall, so they don't need a powered hub. If you try to use mutliple devices that need power on a non-powered hub, that basically splits the power of one usb port between them. Since the monitor plugs into the wall, the hub should be powered, but you might want to check it out. It could be why some things don't work...
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NeddySeagoon
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| Posted: Thu Apr 14, 2005 2:54 pm Post subject: |
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TerranAce007,
Good point. A USB port provides 500mA max for all connected devices. When an unpowered hub is used, thats 500mA total for all ports.
When its a powered hub, its 500mA per port. There are lots of devices out there that want the 500mA all to themseves. e.g USB ADSL modems and anything with a motor in it.
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vonhelmet
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| Posted: Thu Apr 14, 2005 3:25 pm Post subject: |
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I'm fairly certain that there isn't really a distinction between a USB hub and a port. You can hook up 127 devices to a USB root hub on the motherboard, and I'm never seen that many ports on a single hub which suggests you can just daisy chain hubs, which further suggests that any port is a port, whether it's part of a hub or not.
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noup
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| Posted: Thu Apr 14, 2005 3:34 pm Post subject: |
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| TerranAce007 wrote: | | Is the hub powered or not? When you connect peripherals via USB, some draw their power from the USB port and some use external power. For example, my wireless USB mouse and my joystick both draw power from the USB port, so the hub has to have enough power for them, and this comes from an AC adapter. Other things, such as my printer, already use AC power from the wall, so they don't need a powered hub. If you try to use mutliple devices that need power on a non-powered hub, that basically splits the power of one usb port between them. Since the monitor plugs into the wall, the hub should be powered, but you might want to check it out. It could be why some things don't work... |
I know what you mean, since i've already been through this some time ago. The hub is powered, since it's built in the monitor (it would have to be the stupidest decision ever if apple didn't use the monitor's power to power the hub), and also because IIRC all USB2.0 hubs have to be powered (USB2.0 devices consume a lot much power when compared to 1.0 USB devices).
The problem isn't with the power (it's the only device plugged to a powered hub), so it's with the device itself. It's a known fact: some usb devices just don't get along with hubs. They make them have strange behaviours. For example, on my linksys hub, my usb bluetooth dongle just can't send files to my mobile phone. With the display's hub, however, i can't even get the system to use the dongle. And all problems disappear if i connect the dongle directly to one of the motherboard's ports.
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Last edited by noup on Thu Apr 14, 2005 3:40 pm; edited 1 time in total |
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noup
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| Posted: Thu Apr 14, 2005 3:38 pm Post subject: |
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| NeddySeagoon wrote: | noup,
I don't have a USB hub to play with just now but I think it sends all packets everywhere, rather like a Ethernet hub.
Its up to the devices on the end to determine if a particular packet is for them. |
This seems basic enough for it to work. I just can't understand is why some devices simply don't work with hubs... i did search, but didn't find anything meaningful. I came to find all sorts of problem combinations: devices that only work on port1, devices that only work when there is another devices pluged in the hub, devices that only work when a powered hub isn't powered....  )
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