Re: Gigabit ethernet -- what am I doing wrong?

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From
Amancio Hasty <hasty@rah.star-gate.com>
Date
14 Mar 1999 12:47:18
Subject
Re: Gigabit ethernet -- what am I doing wrong?
Message-ID
199903142046.MAA87857@rah.star-gate.com

In reply to
Referenced by

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Not sure what the problem here is . Can a network chipset designer create a
chipset
with a concept of a program store? The answer is yes , if they chose to
implement
a sloppy design thats a different issue.

Amancio


>
> :
> :If the pci device has the concept of a program store like in the case of
> :a bt848 chipset it is conceivable for dma or internal operations to do a retry.
> :It is a different issue if the network chipset designers chose not to have
> :a programmable dma or process control like in the bt848 .
> :
> :
> : Best Regards,
> : Amancio
>
> I know of *NO* DMA device that can do 'retries' of the magnitude that would
> be required, and this in any case does not solve the problem of the FIFO
> overflowing.
>
> Network chipset designers tend to assume that they will be DMAing to or
> from main memory somewhere such that the DMA will not get 'stuck'.
> FIFOs are typically only large enough to hold a packet or two, and many
> can only hold a partial packet.
>
> -Matt
>




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