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queen
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Joined: 19 Jul 2005
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 Posted: Fri May 02, 2008 9:51 am Post subject: confused about difference between uhci with ICH4,6 vs ehci |
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I know that UHCI is usb 1.1 with max speed 12Mb/s and EHCI is usb2 with max speed 480mb/s. Now, how ICH4, ICH6 family influence on UHCI?
My lspci shows: | Code: |
00:1d.0 USB Controller: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) USB UHCI Controller #1 (rev 03)
00:1d.1 USB Controller: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) USB UHCI Controller #2 (rev 03)
00:1d.2 USB Controller: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) USB UHCI Controller #3 (rev 03)
00:1d.7 USB Controller: Intel Corporation 82801DB/DBM (ICH4/ICH4-M) USB2 EHCI Controller (rev 03)
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3 ports in the right part of the laptop (actually all 3 are considered hub) are UHCI which is usb 1.1. and the EHCI is a hidden port beneath the laptop which is almost unusable. What confuses me is the ICH4 (or ICH6) making the usb faster? Can it convert it to usb2 speeds?
How come new motherboards on laptops come with usb1.1? The manufacturer is uniwill. |
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x22
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Joined: 24 Apr 2006
Posts: 208
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| Posted: Fri May 02, 2008 1:59 pm Post subject: |
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ICH4 or ICH6 is just name for Intel chipset. USB 2.0 cannot be faster than 480mbit and USB 1.1 cannot be faster than 12Mbit.
The same USB port should be able to work as both UHCI and EHCI depending of what device is connected.
ICH4-M is not new but according to Wikipedia it supports USB2.0 on all ports. |
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queen
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Joined: 19 Jul 2005
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| Posted: Fri May 02, 2008 2:36 pm Post subject: |
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| x22 wrote: | ICH4 or ICH6 is just name for Intel chipset. USB 2.0 cannot be faster than 480mbit and USB 1.1 cannot be faster than 12Mbit.
The same USB port should be able to work as both UHCI and EHCI depending of what device is connected.
ICH4-M is not new but according to Wikipedia it supports USB2.0 on all ports. |
But those written with ICH4-M is UHCI which is usb1.1. Then how come if I will connect something that supports usb2 it will act as usb2 on uhci? Unfortunately I can't connect anything now to the usb because all of them don't work. ;-(
I managed to fry them all. ;-(
The only port that supports EHCI usb2 is a hidden one beneath the laptop which is not supposed to be for daily usage. |
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krinn
Watchman
Joined: 02 May 2003
Posts: 7470
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| Posted: Fri May 02, 2008 8:32 pm Post subject: |
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| queen wrote: |
But those written with ICH4-M is UHCI which is usb1.1. |
no there are just slave of the EHCI host port
So you can connect anywhere an usb2 device it will work as an usb2 device, or any usb1 device, it will work as an usb1 device.
But as usb2 is crap, you will get disapointed by its speed. In fact, get your hand on an usb1 device to feel the usb2 "power" (crapper than crap is possible! read last comment of http://en.wikipedia.org/wiki/USB#USB_signalling)
if you want long story http://en.wikipedia.org/wiki/USB#Host_controllers to sum up it's for staying compatible with usb1 |
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queen
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Joined: 19 Jul 2005
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| Posted: Sat May 03, 2008 7:32 am Post subject: |
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| krinn wrote: | | queen wrote: |
But those written with ICH4-M is UHCI which is usb1.1. |
no there are just slave of the EHCI host port
So you can connect anywhere an usb2 device it will work as an usb2 device, or any usb1 device, it will work as an usb1 device.
But as usb2 is crap, you will get disapointed by its speed. In fact, get your hand on an usb1 device to feel the usb2 "power" (crapper than crap is possible! read last comment of http://en.wikipedia.org/wiki/USB#USB_signalling)
if you want long story http://en.wikipedia.org/wiki/USB#Host_controllers to sum up it's for staying compatible with usb1 |
Ok, now it's more clear. I had once an experience with usb1. it's very slow. I never tested actual usb2 speed, but from the feeling of timing, it was faster.
Now I can't check anymore usb, because all the ports are fried. ;-(
I consider to buy firewire to usb and put a usb hub to connect all the devices. From the service, they said I will have to change the motherboard which will cost me around 600$.  |
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