Interfacing VS1053b with a S/PDIF transceiver

[BMW850Ci]

Hello guys,

at the moment I'm working on MP3-player as a replacement for cd-changer in my car. The idea is to replace cd-charger by the mp3-player, control them by radio and so on. The connection to the car respectively radio is no problem, the protocoll between cd-changer and radio is known.

The hardware of mp3-player is following:

-> Atmel Atmega644
-> sd-card slot
-> VLSI VS1053b decoder with 12,288Mhz crystal
-> IBus transceiver for the communication with the radio

So, Atmega streams mp3-data from sd-card to the decoder.

The problem: My car have got a DSP. The original cd-changer is connected directly to dsp with s/pdif. The s/pdif input in dsp is an 44.1khz and 2.8Mbps input. Unfortunately the vs1053b doesn't have an s/pdif output, but I2S-interface for interfacing an external DAC or what ever.

So, my idea is to use an external s/pdif transceiver. There are a couple of them. I had a look on Wolfson Micro WM8804 and Cirrus Logic CS8406.

I think, I would like to use WM8804. But, how do I interface the WM8804 to the VS1053b.

Has someone done it?

Thanks & regards,
Heinrich