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I just got a 7 port (downstream) usb hub (ac powered) . If several devices
are plugged into the USB hub, how can several devices transfer data at the
same time ? There is only one upstream port to the computer?
I have an external hard drive, a memory card reader/writer and or
alternatively a direct usb connection from digital camera, a monitor
calibration device. I may add an external dvd writer. And on two other usb
ports on the computer I have two usb printers (with their own ac power)
connected. So the questions pertains more to the card reader and hard
drive.at this time , and later to include a dvd writer
thanks
Frank
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In news:_1Eyf.1141$,
frankg spewed forth:
> I just got a 7 port (downstream) usb hub (ac powered) . If several
> devices are plugged into the USB hub, how can several devices
> transfer data at the same time ? There is only one upstream port to
> the computer? I have an external hard drive, a memory card reader/writer
> and or
> alternatively a direct usb connection from digital camera, a monitor
> calibration device. I may add an external dvd writer. And on two
> other usb ports on the computer I have two usb printers (with their
> own ac power) connected. So the questions pertains more to the card
> reader and hard drive.at this time , and later to include a dvd writer
> thanks
> Frank

Do you have a basic understanding of digital electronics? If not, just
believe that it works. You don't have to know "how". Otherwise, go online
and read the USB interface specifications:

http://www.usb.org/developers/docs/

--
Regardless of Public Law No. 109-162 I hereby affirm that it is
probably my intent to annoy the reader of this post. Get over it.

In article <_1Eyf.1141$>, frankg
<> wrote:

> I just got a 7 port (downstream) usb hub (ac powered) . If several devices
> are plugged into the USB hub, how can several devices transfer data at the
> same time ? There is only one upstream port to the computer?


I don't even know why you thought it -- of course the system does NOT
have simultaneous transfer for all devices. They have to share the
time, and that sharing is managed by the system, so you might even see
a system slowdown during those times.

For the most part, you won't have simultaneous transfers, so you won't
have much problem.