Hello,
I'm trying to use the SPDIF MUX with the OPUS DAC but I have no signal at the OPUS DAC output. I guess it's a configuration problem.
The source of the MUX is a USB input/SPDIF and I2S output converter mounting the Tenor TE7022L chip. The chip should be configured to work up 96 kHz /24 bit, and I use the SPDIF out to feed the MUX.
The four switches on the MUX are set as below:
SW1: low (Normal Phase Detector)
SW2: low (256*Fs) (I set this value according to the WM8741 supported frequencies)
SW3: low (Emphasis off)
SW4: I tried both options
First of all I don't understand how the I2S bus should work. The Cyrrus CS8416 of the MUX is configured to work as I2S 24 bit, but when I check with the scope the signals, it seems to me the world length is 32 bit. The signal frequencies are
for 44.1 kHz sample rate:
LRCK: 44.1 kHz
SLCK: 2.82 MHz (44.1 kHz x 32 bit x 2 channels?)
MCLK: 11.28 MHz (44.1 kHz x 256)

for 96 kHz sample rate:
LRCK: 96 kHz
SLCK: 6.14 MHz (96 kHz x 32 bit x 2 channels?)
MCLK: 24.57 MHz (96 kHz x 256)

The I2S output of the Tenor chip is the same.

The WM8741 on the OPUS DAC is configured in hardware mode, I2S 24 bit, stereo, as described:

I2S = 1
DSD = 0
DEHEMPH = 0
MODE = 0
IWO = 1
DIFFW = 0
FSEL = Z
MUTE = Z (also tried 1)
OSR = I tried the 3 possible options

Reading the WM8741 data sheet I found this:
"The WM8741 will automatically detect when data with LRCK period of exactly 32 BCLKs is received,and select 16-bit mode. This overrides any previously programmed word length. The operating word length will revert to a programmed value only if a LRCK period other than 32 BCLKs is detected".

I'm wondering if my problem can be the PCM format from my USB/Spdif receiver, maybe it's 16 bit and not 24? Is not compatible with the MUX? Any other suggestions?
Any help would be appreciate
Thank you very much.