From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Mon,  5 Jan 1998 07:36:59 -0600
From: G. David Butler gdb@dbSystems.com
Subject: [9fans] Re: DPT controllers (Was etherelnk3.c)
Topicbox-Message-UUID: 6f9934d8-eac8-11e9-9e20-41e7f4b1d025
Message-ID: <19980105133659.vq0Ky7Ua4UW0GLHmRgMnhM_IF5opTveCKdLtYklgUK0@z>

>The DPT controller is the only one that supports RAID, with the added bonus
>of up to 64MB of Cache.

RAID is ok, I guess, but Cache that isn't battery backed up or
doesn't follow the OS's sense of "write this data now, really"
is a BAD thing.

>All the above DPT PCI cards do circles around the 154X series of cards. In
>fact, our lowest end ISA based controllers (I know, John's driver doesn't
>support them, but it can since there is no difference to the interface
>ports and command sets if you force the I/O addresses) are 40% faster than the
>2940s and none of our cards are as slow as the 154X's as well!

I'm interested.  Is the PM2041W a ISA/DMA busmaster?  How many
can I put in one machine (i.e. which DMA channels and IRQ's
does is support)?  What is the DMA transfer speed?

I will try to get a technical reference manual on the PM2041W,
and if successfull, I will give the controller a try.

>But then I am biased ...

That's ok.  I like it better that way.

David Butler
gdb@dbSystems.com