Group Build at the Mason Dixon Hamfest
Robert E. Seastrom
rs at seastrom.com
Tue Oct 26 10:51:37 CDT 2010
"Mike O'Dell" <mo at ccr.org> writes:
> USB these days is pretty-much completely encapsulated by software APIs.
> even USB Class Drivers don't really see hardware except
> what's at the end of the "pipes" (a real USB construct).
> and since the USB transfers are highly-structured, only
> the payload, either async or isochronous, is what matters.
> yes, there are commands and responses, but the nature of
> USB constrains real-time events to isochronous transfers.
and even then it's kind of marginal in terms of jitter, which results
in mega lulz every time someone posts to the ntp list that they're
having trouble disciplining an ntp server with a usb gps puck... :-)
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