[LAU] open hw soundcard with ext. codec

Karl Hammar karl at aspodata.se
Sat Nov 21 06:25:36 EST 2009

> On Fri, 20 Nov 2009 02:00:47 +0100 (CET)
> karl at aspodata.se (Karl Hammar) wrote:
> > So what is your whishlist, I think I have stated mine. What are our
> > common interests and goals ? And what would a first move be ?
> My immediate wish would be for 8 in x 2 out so I could get rid of the
> mixer (just keep a simple mic amp) and more precisely -and repeatably-
> define the input levels.
> Later it would be nice to have both more inputs and outputs so I
> could bring in another rarely used synth and start to experiment with
> surroundsound etc. I should also point out that I also put 2 softsynths
> into the mix.
> I've been working at 44.1kHz 16bit up to now for ease of producing CDs
> (not that I've sold any), but rather think I should be moving up to
> 48kHz 24bit

Ok, let's say you defines the goals, and I define "the next step" 
towards thoose goals. Is that ok with you ?

> ############
> My thoughts would be that a first move would be for a 2 in card with
> ordinary unbalanced line level inputs, not worrying about noise level
> but trying to get a reasonably clear idea of THD as well as hammering
> out a communication protocol.
> My programming knowledge is limited, as are my hardware facilites.

Ok, that would be my job then.

> I can however test things out


> I have an analogue sine/square/triangle
> generator with less than 0.01% sinewave distortion (100Hz-10kHz),

Great, I lack one of thoose.

> pretty
> clean square response and linear triangle output. I used to use this for
> testing amplifiers, along with a twin T notch filter, scope and valve
> voltmeter.

Ok, you do the testing.

> I would be happy to buy a made-up development board with initial
> programming done, and then work in parallel with developers testing and
> improving both the software and hardware.


Would this project plan be ok:

 software and hw: Karl
 testing and spec's: Folderol
 publication via web: anyone??

 git repo: git://aspodata.se/openhw.git
 mailing list: hopefully this list, else I put one up at my site
 web site: ??

 intial platforms (both by Atmel):
 . ATNGW100 (cheap), and
 . AT91SAM9260-EK (expensive)

 Next step:
 . set up development platform
 . simple test with spi and shift registers


Karl Hammar                    Aspö Data               karl at aspodata.se
Lilla Aspö 148                                                 Networks
S-742 94 Östhammar          +46  173 140 57                   Computers
Sweden                     +46  70 511 97 84                 Consulting

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