I2S Input options


#1

Hello,

I would like to know if the tone board is capable to be used as stand-alone DAC (no VIM or other SBC for controling) just I2S in -> analog out) with I2S Input?
I guess it is driven in async mode, so no MCKL signal is needed, correct?

Which board Version would be recommended to use it as I2S or as SPDIF stand-alone DAC?
Where is the I2S signal (DATA, BCKL, LRCKL, GND) to be connected to the board (8 channel Extension or other connector)?

Which I2S format is necessary (thinking of connecting it to a nanoSHARC miniDSP board)?

Thank you!


#2

Hi Freezebox:
Yes, the Tone Board can also work as stand-alone DAC. Actually, the Tone Board digram as below:

And the I2S interfaca is available on the 30PIN FPC connector showed as below:

The Schematic is available at Khadas Download.

Have Fun!


#3

Thanks Gouwa! This is good news!

so better VIM or Generic tone board version for stand alone DAC application?

external MCLK is not necessary, right?

SIN0 … SIN3 are I2S DATA signals from external source, right? So would following connection work from external I2S source?

21 LRCK
23 BCLK
25 DATA
24 GND (e.g.)

which FIR filters are set at DAC output by default?

Thanks!


#4

I think Generic version should be better for you.

Needed, as the ES9038 work as slave mode.

Yes.

You can check ES9038 Datasheet for the details

Have fun!


#5

es9038q2m can run in async mode, so MCLK would not be needed as you have crystals on the board, no? How do you handle I2S input from Raspi that also does not supply a MCLK signal?

Btw. could I also use pin 29, (30), 32 and 33 of the 40pin GPIO as I2S input for stand alone DAC? The 30pin FPC frankly is not very handy for DIY…


#6

the only plugin yet available for the nanoSHARC drives only four of the output channels, so you wouldn’t get the full 8 channels from that DAC board.


#7

Hi,

Are there any other requirements to get the tone board to work as a stand-alone i2s dac?
I’ve tried the following connection with my nanoSHARC dsp:

J5 to 30 pin FPC
3 GND to 18 GND
4 MCLK to 19 MCLK
1 I2S_LRCLK to 21 LRCK
2 I2S_BCLK to 23 BCLK
5 I2S_OUT0 to 25 SIN0

nanoSHARC i2s pinouts can be found on page 10 of the manual:

With this config I didn’t get any output from the TB. I powered the TB using a usb phone charger.

Please advise,
Thank you