Messages in this thread | | | Date | Wed, 26 Mar 2008 22:58:37 -0400 (EDT) | From | Alan Stern <> | Subject | Re: Real time USB2Serial devices and behaivor |
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On Wed, 26 Mar 2008, Greg KH wrote:
> > Is there any reason to think that if I created my own isochronous > > USB2Serial adapter and iso-usb-driver that I couldn't get determinism? > > I strongly doubt it as others have tried and failed in the past.
I don't understand. Isochronous transfers have pretty strict transfer-time guarantees. Why wouldn't this work?
One reason I can think of is that Iso transfers aren't reliable. But then regular RS232-type serial transfers aren't reliable either.
The only other reason is that the USB stack itself has an unpredictable amount of overhead. However I think it should fall within an acceptable range for RT applications.
Alan Stern
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