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SubjectRe: NE2000 slow interrupts safe?
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Richard Gooch wrote:

> On my tests I noticed quite a spread of times. When I send short
> packets, then yes, the times are around a few hundred
> microseconds. However, for longer packets, I was getting up to 2
> milliseconds. And my measurements were consistent with the results
> other were getting with pSOS. I first instrumented almost the whole
> interrupt handler, then later just instrumented the block transfer
> routine and got the same results.

Rule-of-thumb calculation: ISA bus cycle costs 1 us (one microsecond).
1500 bytes -> 750 transfers (Ne2000 is 16bit card) -> 750 us.

I'd say 2000 us is quite long, 300 us is a pretty fast.

I guess that you can have ne2000's that are slower than others. Maybe
300 us was a PCI card?

Roger.

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