[sdiy] Spartan III proposal...

[Magnus Danielson]

From: James Patchell <patchell at cox.net>
Subject: [sdiy] Spartan III proposal...
Date: Wed, 23 Feb 2005 20:38:56 -0800
Message-ID: <5.2.1.1.2.20050223202919.02797418 at pop.west.cox.net>

> Group...
> 
>          I decided to get myself one of these:
> 
> http://www.xilinx.com/products/spartan3/s3boards.htm
> 
>          This is the Xilinx Spartan III starter kit.

I would recommend you to look at these guys:
http://www.xess.com/

Now, look at this board:
http://www.xess.com/prod035.php3

You can do serious damage with that one.

> What I am planning on doing is making a board that interfaces to this that
> will have 8 24bit/192Ksps ADCs and 8 24bit/192Ksps DACS so that the kit can
> be used for doing some pretty powerful Digital Audio processing.  Now the big
> question is, is anybody else interested.  The big bug-a-boo is that the add
> on board will almost certainly have to use surface mount technology...I am 
> personally not happy about that, but that is pretty much the only way the 
> ADCs and DACs come these days.

So what. It's time to learn SMD anyway. We don't have to use 01005 parts, but
0805 most peolpe should be able to handle.

>          I am still trying to decide whether to use Crystal Semiconductor 
> or Analog Devices Delta Sigma parts.  Any suggestions are welcome...Oh yes, 
> I was also thinking of maybe putting a spot on the board for a 
> ATMega128...but I am still debating that.

I don't see what that really would bring for me, but that's my point of view.
What I would do is to include at least one IDE-connector. Now, with that you
have a small hard-disc recording system in no-time but with serious real-time.

A few lines of VHDL code later and you have SMPTE-sync etc. AES/EBU and SPDIF
needs fairly simple driver/receiver circuit.

Oh, word-clock, I want word clock in/out.

What else? Now, the jitter of clocks and a PLL to lock it from word clock.
A low jitter clock is mandatory for good S/N ratios but it should not be that
hard to aceive in reality.

>          Any suggestions?  Any Interest??  Remember, the Webpack that 
> Xilinx provides to program the board with is free...

Interested? Well, I don't know how many of these I would want... 1, 2 or more..

Cheers,
Magnus - another nuthead