ADAU 1787 TDM SLAVE SAI0
Thread Summary
The user encountered issues with no TDM audio input/output on the ADAU1787 SAI0 port in slave configuration. The support engineer provided a working setup example using SAI0 in slave mode, which resolved the issue. The user confirmed the solution worked and shared a full-duplex configuration project file for both ADAUs. Key settings included ASRC for clock synchronization and tristate enabled for TDM communication.AI Generated Content
Hello,
It's been few years now that we're using the ADAU 1787 in our designs.
Today we need to use the TDM port 0 (SAI0) of the ADAU 1787 in Slave configuration.
When we bought our first eval board I remember having trouble using the SAI0 port for TDM.
Back in the days, we only needed one SAI port so we tried to use the SAI1 instead and we didn't know why but the SAI1 port was working but not the SAI0 with exact same configuration.
Today we have an application that require both SAI port so we don't have choice that to dig in the problem.
So we started a new sigma studio project from scratch to use the SAI0 port as slave.
But we rapidely came into the same conclusion that we have no TDM audio in or out using the SAI0 port as slave.
The first thing we tried is to replicate our setup with the SAI1 port and everything worked.
We check the TDM signals (bit clock, LR clock and DOUT) of our master on SAI0 with an oscilloscope and the signals are perfects.
The weird thing is when I change the settings (for example the polarity) I would expect some "white noise ish" if I have the wrong setup. But I get no sound at all like the SAI0 port was not activated, but I checked and everything is well powered in sigma studio.
I'm kind of running out of things to try knowing my SAI1 port is working without problem.
I also tried to create a sine on the DSP and sending it to my DAC with the SAI0 port on slave and that is working too so my ADAU is working but the port SAI0 is not.
I tried with multiple ADAU 1787 and the problem is the same.
What could cause the issue of no sound IN/OUT of the SAI port knowing that it's well powered in the proper window ?
Can you list me all the parameters to look at to make the SAI0 port in slave config works please ?
Have a nice day
Valentin
hardware
ADAU1787
processors and dsp
sigmastudio
Processors and Microcontrollers
SAI0
dsp&processors
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Hello Valentin,
If you could supply a lot more information it would be helpful.
The schematic so we could see how you have the hardware pins setup?
Is the sample rate clock in sync with the master clock that is being fed to the DSP?
Then your SigmaStudio schematic would be helpful so we can see how you have the sample rate converters setup, the routing and those sorts of things?
You can simplify your SigmaStudio schematic if you like to not give up sensitive info but make sure it is functional besides what you are reporting.
Those are a few questions of the top of my head.
Dave T
Hello,
Of course, we're using to ADAU connected together like so :
We're using the TDM with tristated enabled so both ADAU can write on different channels of the TDM.
Everything is working under 48KHz, they both have a Crystal, and they work independently.
The shematic is quite simple, we juste created a sine tone on sigma DSP on both adaus and we're using the SPTIN to output our signal on the DAC.
The first ADAU that is master have the following settings :
The second one have the following settings :
Both have their DAC set like this so we can here the loopback of the signal generated and the signal coming from the ADAU.
Of course this is on SPT1 but we tried the same setup in SPT0 that is not working.
And both have SPT powered on the power menu.
That's the setup test that we have right now but in the past I also tried with a teensy in master and the ADAU in slave with a level converter and it didn't worked too I had to jump to the SPT1 to got it to work.
And same thing here, I tried my config on SPT1 everything is working and when I try with SPT0, the ADAU in slave is not working but the loopback on TDM on the master is working though and we have a signal at the oscilloscope.
I hope that it's clearer.
Hello Valentin,
I'm chiming in for Dave.
I have created your setup, and it works fine on the first attempt. It's strange that you are having issues and I'm not sure what's going on there and is there any hardware problem or something?
My TX side:
My RX side:
RX SPORT and ASRC:
Since both my boards run on their own crystal, I used ASRC.
My setup:
I also attached both projects below for you to try.
ADAU1787_TDM4_TX project.zip
Kindly try these projects and let us know about the results.
As Dave asked, please share your hardware schematics and your SS project, we may find something in there.
Regards,
Harish
SPT0FullDuplex.dspproj
Hi Harish,
Thank you for the working example! We have managed to make your examples work on our board and expanded it to having both ADAUs in the same SigmaStudio project as well as making it full duplex.
I have joined the file if that helps anyone get there at a later date.
Have a lovely day,
Valentin
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