Encoding/decoding extra user data in audio stream
I would like to be able to encode additional user data in an audio stream transmitted from an ADAU1445 and be able to extract that at a head unit using a ADAU1702 (or possibly a ADAU1761). In this way the audio channel wiring can be used to pass commands down the line to a small processor at the head unit (connected via I2C or SPI). The user data or commands would come from the ADAU1445 host processor via SPI.
Is it possible?
I will be using TDM8 16bit and would allocate one 16-bit value as data and commands to the small micro. This could be used to update uP parameters/commands so that it could reprogram the ADAU1702 or update config.
i.e., can the SigmaDSP allow reading or writing of the user data via the SPI port (or should I use a micro with a I2S port and then route via that).
Ian Hickey
Audio Signal Processors
adau1702
adau1445
SigmaDSP Audio Processors
Ian,
I'm not entirely clear on what you're trying to do, but it seems that you're asking about transferring control data over the data stream (TDM) alongside the audio data and having the SigmaDSP extract that control data. I don't believe that what you're trying to do will be possible. The TDM stream should be used only for audio data transfer between two devices, and the control data should be sent over the SPI/I2C control port. If you need to transfer control data from one SigmaDSP to another, you will need to use a microcontroller to handle these control signals.
Please feel free to clarify your original question if I haven't sufficiently answered it here.
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