multichannel audio DAC's

Created Sat, 14 Feb 2015 17:50:10 +0000 by madias

madias

Sat, 14 Feb 2015 17:50:10 +0000

Hello, I got I2s/left/right justified DAC's successfully working on my PIC32MX250F128B (I have several types at home, but prefer the cheap PT8211S, uses BCK,WS,Din, I only need 16 bits). I need at minimum 4 different audio outputs, so one possibility is, to use both SPI ports, doing the same stuff twice. But I believe, there must be a more elegant way to do it? (Ok, there are multi output DAC's, but all of them have big drawbacks, mostly too expensive or have even multiple Data-In pins, so it does not matter whether I use two of 2-channel DAC's or one chip (f.e.: pcm1680 ) facts: each channel should play some short wavetables (about 256-1024 steps/16Bit depth), so no strict synchronization is needed.

Thanks & greets Matthias

Jacob Christ

Mon, 16 Feb 2015 17:21:08 +0000

I have never played with I2S but have always wanted to try. Did you document what you did any where?

Jacob

madias

Tue, 17 Feb 2015 11:49:40 +0000

I didn't document everything, but I commented my sketches. Good starting point are: my and majenkos code at http://chipkit.net/forum/viewtopic.php?f=6&t=3137 and the microchip SPI documentation http://ww1.microchip.com/downloads/en/DeviceDoc/61106G.pdf

and for sure the datasheet of your DAC :)

If you are searching for working DAC's, I've successfully used this ones: PT8211-s (16-bit) (not I2s, but left justified, just a little modification in the code) http://www.aliexpress.com/item/50PCS-PT8211-S-PT8211-SOP8/32259493320.html and CS4334 (24-bit) http://www.aliexpress.com/item/Free-Shipping-10pcs-lot-NEW-CS4334-CS4334K-SOP-8-digital-analog-converter/32249593817.html