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Development platform for a MADI Digital Audio Analyser

MADI is a standard transport for transporting up to 64 channels of 24-bit digital audio over a single-wire (coax) interface.

This project uses the differential interface on the GPIO1 port to interface to a 125Mbps 800mv serial receiver (MADI in), clock recovery circuit and a 125Mbps 800mv serial transmitter (MADI out). Also includes video reference input for, sync separator an AES (AES-3) receiver and an AES transmitter.

The MADI I/O board connecting to the GPIO1 port would include 75-ohm BNC connectors for MADI in, MADI out, analogue video reference in AES in and AES out. It would also include a video sync separator, feeding a digital video frame reference signal into the FPGA through GPIO1.

The FPGA de-serialises MADI in, checks the transport protocol for errors and decodes the audio to allow the audio to be analysed by the FPGA.

Selected audio channels can be picked-off and output on the AES out connector.