Subject: Re: pciide, DMA, and the alpha...
To: None <>
From: Manuel Bouyer <>
List: port-alpha
Date: 08/12/1999 11:28:58
On Wed, Aug 11, 1999 at 09:59:53PM -0500, wrote:
> So, if I wanted "good" performance, I'd probably put in a newer UDMA
> controller, but it might work well enough.

Note that the CMD0646 is a cheap but weird chip. Especially it can't use
both channels at the same time, access has to be serailised (that's because
some internal registers are shared between the 2 channels).
For a ccd or raid this can divide performances by two.
If you can, add external Ultra-DMA controllers (CRC is a good thing
to have also :)

Manuel Bouyer, LIP6, Universite Paris VI.