I'm working with the C2000 teaching materials to learn how to set up the McBSP & SPI interfaces to use the AIC23 on the Explorer. I took the example code (which only dealt with generating a signal to output, and not the other direction,) and modified it such that it would "play back" the input to the AIC23 to the output (which would verify that I've set the McBSP and AIC23 up correctly, and can then do other fun things.)
After ironing out the bugs, I had what appeared to be a distorted version of the input. The "song" I put in (via a Ipod device) was recognizable, but there was a LOT of static. I'm not sure exactly what would be causing this. My initial guess comes from the fact that the AIC23 has a "input word length" option (which in the example was set to 32 bit) but no "output word length" option. I'm guessing that the output word length is fixed to some length, probably 16. Since I'm reading from the McBSP like it's a 32 bit value (since I figured if I was outputting a 32 bit value I could probably read in a 32 bit value) that could possibly cause a problem. Unfortunately, looking through the AIC23 datasheet, there's no mention of this, so I'm not sure if that's the problem...
I'll post my code if asked, but I'm figuring this is something simple enough that I'm just overlooking something sort of obvious. Are there any "common pitfalls" pertaining to working with this that I'm probably falling into?
(Also of note: I understand that I'll probably have to eventually use the DMA in order to get things done on time, but right now I'm just trying to get this set up, and then, if needed, I can add the DMA in later...or at least I think that's how I can get it done.)