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RE: is there a market for this?
From: jan.novak () aliatel cz (Jan Novak)
Date: Tue, 22 Jul 1997 09:51:44 +-200

There are ATM cards on the level of OC3/OC12 for PCI, SBus... But they have usually their own i960 for SAR functions 
and originate a interupt only when have cell to transfer over internal bus, not with every byte accepted on input.
----------
Od:     Raymond Wong[SMTP:negativl () netcom com]
Odesláno:       21. července 1997 18:44
Komu:   nanog () merit edu
Předmět:        Re: is there a market for this?



The discrepancy is caused by the same limitation that allows the old PC-ISA bus
to handle a theoretical 8(?16?)) Mbytes, but start to choke long before a
rs232 serial port reaches 115kbps.  It's not the processor or the bus,
it's the number of interrupts the serial connection is generating.  Move
away from interrupts, increase the amount of data per interrupt, or whatever,
and the limits increase.    Doing it at the T level on PCI is just a matter
of scale from the 232 level on old PCs with ISA.  Discussing raw bandwidth
just misses the point.  

That's my immediate reaction, anyway.  Does anyone actually know better how
this all works, or are we going to read another 3 days of hearsay?





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