Topic: Designing a SoundCard from Scratch?

[Xer0]

Hi Guys

im currently reading the CMedia Datasheets and i am curiious about the Idea, to build yourself a Card. with only the Features "WE" need; 6-8ch analog output, and maybe line/mic in for some analytical use, fe analog'ed feedback from the galvo loop signals to build a scansafety in software on the host pc; or other status information of the scanner...
maybe the chip can be even set to provide higher voltage than usual and do differential output with 0V as zeropoint, so you dont even need correction. or write a custom firmware that installs it as standalone device, so it wont mess up on other computers or when you use software DSP's.

The Question is, would that be possible? CM106 seems fairly easy to use for me, all DACs in it. While CM6220 seems to need external ones to output analog. # For what? to have it smaller!

[cfavreau]

How about using a USB Micro to do the job?  Then we could add some laser safety features too.   I have been looking at the LUFA package for USB AVR's and it includes a USB Sound 1.0 example.  From what I have read it is fairly simple to add channels (the example is for 1 only).   The only other question is can it support 5 or six channels at 48 kHz output rate?

Regarding the chips:
I would say for simplicity ... use the one with the DACs inside.
What other differences are there?

[James]

I don't think C-Media makes the CM-106 anymore. They probably don't make the 6206 either. It takes a long time to develop a chip like that and while it is being done it's top secret information. Then it goes into mass production and a billion of them are made and sent out to generic device manufacturers. By the time we see them CM has moved on.

James. 

[Xer0]

Thats bad. you asked bout differences? The new chips have 8ch but no direct audio outputs. thes use "HDA Link" to digitally send Audio to a Codec Chip, and this one has the DAC's now. and lots of for us uininteressting functions. 106 is well documented, every Pin desribed and so on. too bad its not avaiable anymore. maybe we could then get them "trashed" from the hardware distributor who dont need them anymore?
yes you could use the mic/line in ports on the chip for bidirektional communication!

[James]

If you REALLY wanted to, you could find some assembled devices with these chips and remove them.

But at that point, you might as well just tap the caps and get on with life.

James.