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RussMartin
- 7th July 2008, 19:02
Some while ago, I ran across an application using a PIC to manage digital audio delay.

I thought I had printed the article and/or bookmarked it, but I can't find it now.

Can someone please point me in the right direction? Thanks!

skimask
- 7th July 2008, 20:55
Some while ago, I ran across an application using a PIC to manage digital audio delay. I thought I had printed the article and/or bookmarked it, but I can't find it now. Can someone please point me in the right direction? Thanks!
I don't know if this is what you're looking for, but...
Awhile back, I needed an audio delay to sync up audio with a PIC based spectrum analyzer. Specifically, I needed about 72ms of delay.
I ended up taking a stereo 16 bit A/D converter at about 40Khz, reading that with the first PIC18F4620 into the onchip ram (3900-ish bytes worth), and then shifting (first in-first out) to another '4620, then another, 4 total in the line. The last (5th) PIC was connected to a stereo 16 bit D/A at the same sample rate. Ran all of the PICs off the same oscillator, sync'd the A/D and D/A converter and shift clock up to another PIC generating a ~40Khz signal. Worked good enough for me. Don't tell Mr_E, because he'll start in talking about distortion, aliasing, and so on :D Like I said, it was good enough for me in an outdoor environment.
And again, this was awhile back. I've since tore the project apart. I'm sure I've still got the schematics, firmware, notes, etc. if this is what you're looking for.