Configure SPDIF out using ALSA/MCASP on BeagleBoneBlack?

Hi

I would like to configure my BeagleBoneBlack to output data in SPDIF format.
currently the BBB is configured by default to output audio on HDMI.

Is it possible to add an SPDIF output instead?

If yes, what pins should I use?
And what software needs to be changed?

Thanks

/Jacob