Topic: MADI 192kHz Frame Formats

I am using the HDSP MADI card and would like to interface with the MADI I/O using the 192kHz MADI.

Since AES10-2008 does not define a MADI frame format for 192kHz, does the HDSP MADI card extrapolate the same formats as 96kHz? In AES10-2008, with 96Kz Sampling, there are two modes, one where the Frame clock (Fc) = Sampling rate (Fs), and one where Frame clock is 1/2 sampling rate. With 192KHz, there should be one additional mode... where Frame Clock = 1/4 Sampling rate so there will be 3 possible modes at 192kHz.

Fc = 192KHz, Fs = 192KHz
[Start Frame] CH0 | CH1 | CH2 ... CH16 [End Frame] 16 total samples/frame

Fc = 96KHz, Fs = 192KHz {Double Rate}
[Start Frame] CH0(n) | CH0(n+1) | CH1(n) | CH(n+1) | ... CH16(n) | CH16(n+1) [End Frame] 32 total samples/frame

Fc = 48KHz, Fs = 192KHz {Quad Rate}
[Start Frame] CH0(n) | CH0(n+1) | CH0(n+2) | CH0(n+3) | CH1(n)... CH16(n+2) | CH16(n+3) [End Frame] 64 total samples/frame

Does RME support all of these modes or do you do something different?

2

Re: MADI 192kHz Frame Formats

We only support 192 kHz as 48k frame mode (quad sample multipexing). I am not aware of anyone using 96 kHz frame with double sample multiplexing.

Regards
Matthias Carstens
RME

Re: MADI 192kHz Frame Formats

Does that mean the frame looks like this then?

[Start Frame] CH0(n) | CH0(n+1) | CH0(n+2) | CH0(n+3) | CH1(n)... CH16(n+2) | CH16(n+3) [End Frame] 64 total samples/frame

With 4 consecutive samples per channel with CH1-8 on one phase of the WCLK and 9-16 on the other...

Or, is there 2 consecutive samples per channel for CH1-16 on each phase of the WCLK?

4

Re: MADI 192kHz Frame Formats

4 consecutive samples.

Regards
Matthias Carstens
RME

Re: MADI 192kHz Frame Formats

Thanks a lot, you have been incredibly helpful.