Digital designs?

The Dark force of dance batzman at gist.net.au
Thu Jan 8 01:09:35 CET 1998


Y-ellow y'all.

At 09:48 PM 1/6/98 -0500, Soundwave [Chad Gould] wrote:

>OK. Even so, it IS proprietary hardware. Using your own hardware has a
>LOT of advantages than relying on Windows sound drivers (which the bulk
>of what you call "toys" use). You can code directly at the assembler
>level with that. Reality uses this principle, and I imagine if there's
>no DSPs tripleDAT does too. 

This is pretty much what I'm saying. You're either a coder or your not. If
you wanna do this stuff you have to think long and hard. High level
languages are good for the high level fucntions. Front end GUIs 'n' stuff
but whether you're looking at coding on a DSP or coding at BIOS level on a
PC hardware platform you're looking at assembler. There is no other way to
do it. What most people do is that they write optimized modules in assembler
for inclusion in larger "C" programs to take care of the dirty work. Then
write all the high level fucntions at a higher level. Drivers by default
should and generatlly are written in assembler.

Although you can get C compilers for a range of DSP products, when it comed
down to it, there's only one way to bolt the bits together...

So what I'm suggesting is that if you're gonna have to do that anyway, why
not save yourself the hassle of re-inventing the wheel and use some
pre-existing, and dare is say, "CHEAP" hardware to do your job.

>That might be interesting... TBS as in Turtle Beach Systems? 

Yea. Now there's a bunch of scumbags I really don't feel like advertising
for. Still...

>Pinnacle Project Studio, Multisound Pinnacle, and Multisound Fiji have
>the 56002 DSP.

err not that I'm aware. Though I've never used a Fiji. I believe it only has
a motorola 68K derivative on board. AS does the Maui and the Multisound
Montere. The reason is that they have a thing called an ICS2115 on board
which is a dedicated sample playback engine.

The Pinnacle has a complete Kurtzweil K2000 VAST chipset on board. This is
in essence just a Gee Wizz sample playback engine with a dedicated DSP FX
processor. Though I'm not sure entirely that this isn't a DSP56K. But you
can bet your wedding tackle it's not very user accessable. The TBS 56K is
the only card I know of with a redilly hackable DSP chip on board. And that
it was designed with exactly that in mind. I should point out that when I
say DSP56K I am talking generically but in this case, yes it is the 56002.
There is no actual part number DSP56000. It's just the generic family.
Various other's in the family are either blown out or stripped down versions
of the 56002.

>Hmm. Hackable you say? Hmm. I was looking into getting a
>pro-spec recording card along the lines of the Card D and the Layla/Darla
>(sorry, TripleDAT isn't $500. (: ) and I dunno how the TB cards rate.
>(Fiji is $360 list) But that's off topic.

Yea I know Triple is expensive. When I bought mine it was the only thing
like it on the market. And is still the only thing that can do the stuff it
does. The Layla/Darla/Toola, Doola and Foola cards are pretty good and run a
close second. Nothing much beats the tripleDAT though. You have to
understand that I was the first person in Australia to have one and I've
never used anything else personally. Though in my somewhat spazmotic
association with Derringers I get to try all sorts o' stuff. And over the
years I must have bought, paid for and discarded more sound cards than most
people have had good sex. I got the 3DAT because it was the only thing that
could lock to a sequencer running concurrently on the same platform. Any
sequencer! And! it came with it's own excellent back-up system. More
recently, because of my years of exprience with it, I get asked to do demos
of it. Now I've never used anything else and I came to expect that all HD
recording systems would be similar. Yet I can literally hear the jaws of
Pro-tools and Prisma users hitting the floor behind me when I do stuff. I've
come to understand that Pro-tools isn't even close. And that's scary because
pro-tools _IS_ supported by a heap of DSP systems and costs about 40 grand
here for an 8 channel system. So in those terms, TripleDAT is quite inexpensive.

But having said that, I only used it as an example because it's the only
thing I can think of which is in the order of complexity we're talking
about, does not use DSP or other hardware support and runs under windoze.
And gets away with it...

Now Finally I really need to make this point again. The hardware support
that TripleDAT has is no more than any other sound card. The only difference
is that it has switching and routing for an S/PDIF tranceiver. If you
remember, I explained that an S/PDIF tranceiver can simply piggy back on an
I2S bus. All you then need is an interface between ISA or PCI to I2S. There
isn't even any buffer ram on the 3DAT card. There's just an orchestraing
Microprocessor and a hybrid chip with the codecs and S/PDIF tranceivers in them.

You may be getting confused with the new 3DAT t-16. This gives full 8 stereo
channel Analogue and ADAT support. There is a big chip on this card but it
isn't actually a DSP. It's what is known as an ALTERA FLEX 10K. If you
haven't heard of it, it's another technology that may be worth your
investication. Xilinx is another but I can really only speak for Flex 10 K
since it was technology we were employing @ G-FROG. Essentially it's what
might be termed "Soft hardware" It's a field programmable logic array but
it's totally volitile. That means as soon as the power goes off it forgets
what it is. It has just enough smarts to be able to read it's configuration
out of buddy ROM/RAM which lives along side of it. We're talking 100K gates
here. More than enough to do a pretty respectable optimized DSP system. And
it should be noted that it is common practice to include a direct PCI
interface in the programm and it is fast enough to do that with no timing
problems.

This stuff is way wicked and worth you looking into. The nice thing about
Altera is that they give you the software free. You will of course need to
buy something to programm with. The best bet would be to buy a complete
development system from ALTERA but you can do it yourself. And there are a
range of options available from a simple device programmer that will just
blow a buddy-eeprom from a PC.

I know this is dobbing him in but perhaps Paul S could give a short run-down
on Xilinx if we all asked nicely. I'd be most interested my self and Paul is
_THEE_MAN_ on this stuff.

Hope this helps.

Be absolutely Icebox.

>
>-- 
>Chad Gould aka Soundwave                 |studio: 9 real synths
>internet: cgould at gate.net                |and a cheap Casio
>Make Happy the Harmonica Happy!
>http://tilt.largo.fl.us/ - MST3K / Samples / Synth FAQ / More...
>
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