At 04:24 PM 6/1/00 -0400, Joy Ganguly wrote:
>Dennis wrote:
>
>> At 12:13 PM 6/1/00 -0600, Warner Losh wrote:
>> >In message <[EMAIL PROTECTED]> Dennis writes:
>> >: Have you done bus performance testing with this card? Given the
>> >: architechture of the AMCC part, it seems highly improbable that you
will be
>> >: able to get high throughput with such a card. Because the AMCC part
>> >: requires external logic it is impossible to do pass-through single cycle
>> >: bursts, which is required for efficient utilization of the PCI bus. Once
>> >: you begin holding off cycles the PCI bus totally pigs out (which is why
>> >: virtually all high-speed pci solutions are single-chip type designs).
>> >
>> >Yes. I've done drivers for several cards with this design. The AMCC
>> >part is very fussy and will often lock up the bus unless the card
>> >designer has put enough extra logic on the card to cope with the
>> >oddities of the card. Sadly, many don't.
>>
>> We used it on our first (and now defunct) pci board, and we didnt have
>> trouble with lockups (there are quite a few errata that have to be
>> addresses), but the arbitration was pitifully slow. There was no way to get
>> high throughput across the bus. We completely rejected it for use on
>> T3...i find it interesting that someone did an OC3/ATM card with it.
>>
>> Dennis
>>
>> Emerging Technologies, Inc.
>>
>
>well the problem seems to have been with the motherboard. i changed the
>motherboard and the card is working.
>we are using "point" oc3 card from 'applied telecom'. we have not done
>any
>performance testing. the card is mainly meant for monitoring.
of course this discussion has nothing to do with your problem...but Im glad
you figured it out :-)
good luck with your throughput.
DB
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