15 Dec
2004
15 Dec
'04
5:03 p.m.
On Wed, 2004-12-15 at 11:24, Mark Knecht wrote:
On 15 Dec 2004 10:29:38 -0800, Fernando Lopez-Lezcano
<nando(a)ccrma.stanford.edu> wrote:
I'm not so sure PCI would be the best answer for a project like this
one, and that was the point of the question. I would be concerned about
the tools. Xilinx arrays will probably need closed source and expensive
software.
What I was thinking about was this:
- 1394 chip (off the shelf, no programming)
- (high speed?) ucontroller (off the shelf, use one that has open
source tools for programming it).
- line drivers for spdif and/or ADAT (driven from the ucontroller)
- DA/AD chips (driven from the ucontroller)
So, this approach would reduce the problem to hardware interconnection
of logic parts (rather easy) and firmware for the ucontroller (hard).
The question would be, it this doable with available ucontrollers that
have open source compiler toolchains?
-- Fernando
On Tue, 2004-12-14 at 09:46, Mark Knecht wrote:
I believe this is (more or less) completely possible. Let's use two
of the recently maligned RME's products as an example - the HDSP 9652
and the Hammerfall Light. (Hey - imagine that?! I chose the two cards
I own!) ;-)
[MUNCH]
With the price of Xilinx chips coming down all the time, and with
functionality going up, I see a small card with one large FPGA, a
small eeprom to enable a PCI enterface in the chip, and some
transceivers for ADAT and/or s/pdif. I am just guessing that even in
small volumes this can probably be built for under $300/card. (That's
a total guess.)
The nice thing about this, in my mind, is that when Xilinx comes
out with each new generation you can imagine putting a bigger Xilinx
chip on the same card and programming more interesting things, like
hardware mixers. This is rally all RME did between the Hammerfall and
HDSP line. (I'm being purposely simplistic here.)
There are certainly HUGE challenges for a group of folks like us
doing this. Verilog (or VHDL) design, which I don't do, compiling that
code into something that programs the Xilinx chips (Symplicity?)
assembly, testing, etc., but none of it is unsurmountable. It just
takes some vision and, unfortunately, some money unless we can get
access to some Open Source tools or, possibly, commercial tools
through some friendly company.
Doing this as a 1394-based external unit is really interesting, but
is more complicated. Maybe PCI is the best for now. On 14 Dec 2004 10:03:31 +0100, Andreas Kuckartz
<A.Kuckartz(a)ping.de> wrote:
Maybe, maybe not. One quick question I have been meaning to ask. Would
it be possible to completely drive the card with firmware? What I mean,
can all the packet processing be handled by an onboard processor in the
soundcard? No gate arrays? What I picture is of-the-shelf components
only... [*]
Lee Revell wrote:
> Christ, what the fuck country do you live in? Don't you understand the
> concept of people having bills to pay? Or do you just assume the RME
> guys are independenly wealthy and just design sound cards for fun?
Interestingly some people seem to be existing who are working on Linux for fun.
Also there is a concept known as "Open Source Hardware" which was mentioned
here
before.
Actually, it was Lee and I (I think) who were the main proponents of
the Open Source Sound Card idea. Funny how that works out at times.
My current thought is that there aren't enough people interested in
doing it. Maybe I'm wrong?