Here's a program in pure assembly code for audio in-out (echo or talk through) for the BF706 EZ kit mini. It includes routines to set up the SPORT and the codec, so no other resources are required.
Question - is it possible to use a single instruction to poll a bit on a control register? The old Freescale DSP563xx family used something like: jclr #3,x:$ffffb7,*, which means "keep testing bit #3 of the register at address x:$ffffb7 until it goes high. The attached program uses polling to test of the input buffer is full, but it uses three instructions. It would nice to reduce this to one.