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Re: [rtl] IP useage from rtlinux, reply to Richard Teltz
Reinhold J. Gerharz wrote:
>
> At 23:21 06/10/1998 +0200, Thomas Wuensche wrote:
> >Richard Teltz wrote:
> >
> >> ARCNET, CANbus, etc are not supported by a terrifically wide number of
> >> vendors, and QNX is great if all your machines are QNX (kind of like
> >> MicroSoft).
> >
> >What is your background information to state that CAN is not supported by
> >a wide number of vendors? This may hold true if you compare CAN with the
> >whole range of office applications, if however you compare realtime
> >related applications, I think it is wrong.
>
> Don't forget, CAN is also prioritized. The destination address of a
> packet is also its priority. When collisions occur, the lower priority
> device is expected to back off.
Yes, that's the important point. CAN has priorities on the lowest layers,
thus the high priority message always is transmitted immediately. The lower
priority message is transmitted immediately after the network is free again,
without any arbitrary backoff recovery time. Thus delays occur only in the
moment of true overload, and that's the case for any realtime system.
But a small correction: CAN does not have destination addresses, the id is
kind of a source address. CAN is a broadcast system.
> http://www.llp.fu-berlin.de/pool/newproj/CAN/ is a good starting place
> for Linux users.
Thanks for mentioning this site. I know it, since we are sponsoring it :-).
Hopefully we have CAN drivers for rt-linux soon, since with CAN it does really
make sense to have support for realtime operating systems.
Thomas Wuensche
> --
> Reinhold J. Gerharz http://www.erols.com/rgerharz
> PGP Key at http://www.erols.com/rgerharz/pgp/public-key.asc
> "The only good spammer is a DEAD spammer!" - Anonymous
>
> --- [rtl] ---
> For more information on Real-Time Linux see:
> http://www.rtlinux.org/
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-------------------------------------------------------
--- [rtl] ---
For more information on Real-Time Linux see:
http://www.rtlinux.org/