Re: Ethernet card- alternatives

[bazyar@mrcnext.cso.uiuc.edu (Jawaid Bazyar)]

jaj4922@fert2.fe.psu.edu (Jason A. Jeffries) writes:

>That's strange; if our ports can really go 233k, I wonder why we can't use
>them as serial ports that fast...

  You _can_; however, the reason AppleTalk works well is that at the 
beginning of each packet is encoded the number of bytes to follow.
The AppleTalk interrupt handler stays in a _very_ tight loop and reads
exactly that many bytes. All from one interrupt.

  Asynchronous serial at that speed, however, would require an interrupt
much more often than one for each packet; in fact, it's too fast
asynchronously to matter - the GS can't handle it without losing data.

  If you wanted to implement some asynchronous-yet-fixed protocol,
you could probably get it to run at that speed.

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