Audio Multichannel input?


Hello Khadas,

The Vim seems to be a great SBC considering it’s technical features, I hope you will be able to handle the required firmware/software part to gather an community around.

I’m glad you just released a brief S905X description (can’t wait for the complete datasheet !), that confirm that the audio inputs are more limited than the outputs.

For an audio project I was looking to process a multichannel audio stream through the i²S interface, do you confirm that the board i²S input is limited to 2 channels, and that the i²S output allow 8 channel ?

Is there any other way i can send an audio stream (coded or pcm) to the Vim (from a blu ray player, from a tv, or else) ? Should i use the s/pdif, or add an Hdmi-input extention ? Or is it a S905x limitation that can’t be overcome ?


Analog audio out

We’ve designed a Karaoke product based on S905X for your reference:

  • I2S bus for audio up path
  • PCM bus can be for audio down path

Check Popsical Website for further information.


Thanks for your reply, however that doesn’t seem to answer to my first question : what are the audio input capacity of the Vim Board, considering the multi channel aspect, according to i²S, S/Pdif ?


The I2S bus is available on 40pin GPIO, it means that you can design with any I2S device for VIM


I did saw there are 5 pins for i2s purposes, But :

  1. is this bus avaiable up to 8 channels (input) (i.e. 5.1 or 7.1 system) ?
  2. Could he send an 8 channel signal at the same time ?



Hi, Dekron:
Yes, the I2S but support 2-channel input and 8-channel output, you can check the CPU datasheet on Khadas Docs for details:


Hi gouwa,

Sadly, as i thought … so the Vim board is able to handle an 8ch audio signal through wifi, ethernet or any local storage.

But it won t be able to receive an audio 8 channel signal through a wired link, even if we add a little hdmi-in connector ? That’s unfortunate if that s true.


VIM doesn’t support HDMI-In.

What do you mean here?


The S905x allow up to 8ch output. That means, i guess, that he can process such data according to the following cases :

  • Multichannel file on a local or distant storage (access through any wire or wireless network connection, even USB). (Am i wrong assuming this ?)

But you confirmed that the board input through the i²S bus can’t handle more than 2 audio channel (for example through an S/PDIF connector).

My main goal was to use a VIM board to process audio data to improve my speakers response (audio filters, fft, convolutions, fir, iir …) instead of a dedicated DSP board, coming through the TV or through my blu ray player.

So even if I would be able to handle any musical content, that won’t be the case for home cinema content, where I would have to downmix the 5.1 stream into stereo. My last question was then to know if, besides the i²S bus, there would be any other gate/feature i could use to be able to send the audio multichannel stream of a movie to the Vim ?