Tone Board & BT CSR8675 via S/PDIF


Can I connect this BT unit by using S/PDIF in on the Tone Board?

From my understanding it should work?

If the device outputs coaxial SPDIF, that should be able to supply SPDIF signal to the TB’s SPDIF input jack.
Any SPDIF coaxial(not optical) output should be able to supply signal to the TB.

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Thx for the answer.

I think the SPDIF signal is coax, for sure no fiber.

Should be possible to attach via a cable from pin1 of the BT board to pin13 (GPIO female header) of the tone board, right?

I am not certain about that. I think there is a logic as to where the TB takes incoming signals from, based on how it is connected otherwise.
From page 6 of the TB schematic, the section on SPDIF mode…

I am not familiar enough with this function to give you advice on it.
One of the Khadas Team will be better able to answer this. Maybe @tsangyoujun will have the answer.
I will try it and see, but it will be tomorrow night before I am with the TB.

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Awesome :slight_smile:

I’m super confused after hours of reading … and have no clue yet.

What should work anyway is to use the external SP/DIF Coax, cause it os supposed to work.
Should be possible to add a wire there.

Let me do some checking on my TB tomorrow night.
Normally when the TB is used as a standalone device, the source’s SPDIF output signal will be connected to the RCA input on the TB, when powered via the TB’s USB port.
When the TB is connected to the VIM SBCs via the GPIO, power is supplied by the VIM’s GPIO. Under that circumstance, the TB’s SPDIF RCA jack functions as an SPDIF output, the signal is supplied by the VIMs.
If you power the TB with USB, I am not sure pin 13 could be used for the TB’s SPDIF input. As previously stated, I am uncertain about this. I will try it when I get to the TB.

@Sui77 Update: The Khadas SBCs are the only SPDIF sources I have at the moment. Both had ATV ROMs installed. I was unable to get SPDIF output from them. So I was unable to make the test with the TB. I will try to look into it further over the next day or two.


Hello! @tsangyoujun is now designing a new radiator, which is probably why he’s busy :wink:

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Yes, I assume the whole team is busy after the extended time away. Busy and excited to get back to it.:slightly_smiling_face:
Look forward to the new radiator.

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THX for the heads up.

I’ve read a bit more and maybe you are right that SPDIF is not active when using the GPIO (sounds logic).
Perhaps it would be possible to use the SPDIF connector directly, but I’m not sure if the format of the signal is in the right format (SPDIF digital differential analog audio VS coax)

I2S might be an option: I2S Input options

BT board