MP3 Working, on to the Schematic

I was fairly convinced that MP3 quality problems were due to data rate, that is I wasnt feeding the VS1053 fast enough.  So I played with a lot of things in the loop to increase the idle time.  But nothing worked, no matter what I did, the quality never changed.  Then I remembered that the FLASH SPI clock was still running at 200K from when I was just trying to get it to work.  Because of the resistors in the PIC32MX470 curiosity board, going much above 1MHz causes the waveforms to degrade.  (I need to jump these on the SPI bus.)  After moving the SPI clock up to 1MHz, I get near CD quality, at least for my poor hearing (too many years in Naval aviation). 

I still need to optimize the idle time, since there are still motors, LEDs and the BLE interface to service.  But that come with time.  Right now I am working on the schematic, so I can get the PCBs out to fab and built.