https://forum.pjrc.com/threads/28639-S-pdif?p=159530&viewfull=1#post159530

Adding CPP/H implementation files, plus example sketch and update to
HTML file.

One write was out-of-bounds due to worng address put (I was using the
device address rather than the register address), another write
overwrote the Power Management register with the Mode Control register.
Now everything works. Added two exampes: SineOutTest that puts two
sinewaves on the outputs, and PassthroughTest that connects the two
inputs to the two outputs.