External Audio DSP Processor Project

XCore Project reviews, ideas, videos and proposals.
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Folknology
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Post by Folknology »

You could add a midi interface easily enough to the XC-!a for control purposes see the midi section in the Audio MC 2.0 reference design I mentioned.

For good audio I/O you may as well add a CODEC rather than a plain DAC it will be better quality and probably cheaper..

For monitoring just build a D-Class output, Xmos have some good code examples for this.

All of that would make it lower cost.
Last edited by Folknology on Mon Oct 04, 2010 7:05 pm, edited 1 time in total.
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lilltroll
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Post by lilltroll »

Also your chip choice may lead you to using an L2 rather than a G4 as this is already a reference platform for xmos audio see USB Audio 2.0 multichannel ref design. This would provide a good basis for your design as the schematics are already available.
Al
For G4, you can also take a look at the schematics for the XDK http://www.xmos.com/products/developmen ... opment-kit , it has the XTAG&serial FTDI + USB2.0 + Ethernet and a stereo CODEC. If you want to keep it simple, use a CODEC with a on-chip voltage regulation and already existing "drivers" (XC-code).
Probably not the most confused programmer anymore on the XCORE forum.
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Folknology
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Post by Folknology »

Nice one Mika I forgot about the XDK that has some really good references that are applicable to the XC-1A and G4
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williamk
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Post by williamk »

Thanks guys, I will check this out tomorrow. :mrgreen:
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lilltroll
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Post by lilltroll »

Here is an other old project:

A MIDI synth with LCD
Image
http://archive.xmoslinkers.org/node/122:
Probably not the most confused programmer anymore on the XCORE forum.
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williamk
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Post by williamk »

Nice one, thanks. :geek:
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lilltroll
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Post by lilltroll »

williamk wrote:Nice one, thanks. :geek:
This one is :ugeek:

http://archive.xmoslinkers.org/node/240

And then play McGyver :mrgreen:
Probably not the most confused programmer anymore on the XCORE forum.
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paul
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Post by paul »

williamk wrote:Ah, can this be moved to Project Proposals, please? :oops:
Done!
Paul

On two occasions I have been asked, 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question.
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williamk
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Post by williamk »

Ok, some more talk. How hard is to interface with the ethernet (RJ45) via a home-network? I mean, the idea is simple, send a chunk of audio and midi information and collect the last buffer. So it works like this:

1) create small buffer
2) send audio and midi to buffer
3) release

next set of samples

repeat {
1) read previous buffer
2) clear buffer
4) send audio and midi to buffer
5) release
}
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Folknology
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Post by Folknology »

Well for the Ethernet you will need 5 or more threads ( 2 for the Rx and Tx Mii layer and 2 for the Mac Rx and Tx layer) . On top of that you could use TCP/IP sockets which are standard and easy to deal with at the other (non Xmos) end. however on Xmos the TCP/IP code is plain nasty. You could communicate directly over Ethernet using AVB or some such for which standards exist. but basically expect to dedicate a most of the threads on a given core unless Ethernet on Xmos has been thread optimised for AVB in another way compared to the provided Ethernet 1v3, I'm no AVB expert.

On top of that it should just be standard midi, audio and I/O user interface stuff which should be more straight forward.

regards
Al