Feedback loop doesn't work on ADAU1787 FastDSP
Hello,
I am working with an EVAL-ADAU1787Z and want to create an algorithm containing a feedback loop in the FastDSP. However, I can't get it to work. For testing I'm trying to implement the simplest version of a feedback loop I can think of. I am generating a sine tone in the SigmaDSP. I have built equivalent diagrams in the SigmaDSP and FastDSP and am sending the output of each of them to a DAC. When I run this project (also linked in this topic) I hear output on the left output (SigmaDSP), but nothing on the right output (FastDSP).
I have already checked if the signal routing is correct. It all works, until I add the feedback loop in the fastDSP part. I have no idea what's going wrong here. I'm hoping someone can clear this up for me.
With kind regards,
Thijs Hekman
file:///home/thijs/Documents/Moonshine/FDSPfeedbacktest.PNGFDSPfeedbacktest.dspproj
hardware
ADAU1787
sigmaStudio 4.7
Integrated/Special Purpose A/D Converters
sigmastudio4.7
ADAU1787 evaluation board
EVAL-ADAU1787Z
Audio CODECs
fastDsp
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Hello THekman,
Thanks for the report and the example project. We will investigate this and report back.
Dave T
Hi Dave,
Thank you for your response. I hope you can figure it out, I would be really useful for me if I could make this work in the FastDSP. Have you managed to reproduce my problem?
With kind regards,
Thijs
Hi THekman,
Apologies for the late response, but I just took a look at your example project, and there appears to be a bug in the Feedback block in the FDSP. Your setup looks good otherwise.
I've brought this issue to the attention of some DSP engineers who write the algorithms to these blocks, and they will be taking a look to improve this issue as soon as possible.
The Feedback block does provide support for blocks such as Mixers, Limiters, and Filters, but it appears that connecting the output of the Feedback block to the Linear Gain and/or Inverse blocks are where the problems are occurring. Besides seeing no output for the FDSP, there appears to be no OP code written for the FDSP when the Feedback block is connected to the Linear Gain and Inverse blocks.
I will follow back up with you once the DSP engineers have resolved this issue. Thank you for bringing this to our attention. Hope to hear back from you soon!
Best,
TM
Hello, any update with this bug?
Hi IHu,
Unfortunately, this bug has not been addressed yet, but it is on the list of fixes and improvements that will be included in our newest software - SigmaStudio+. We are currently working on the 2.0.6 release, and we hope to include the bug fixes for the FDSP Feedback block in the next release.
I would suggest getting familiar with the SS+ software in the meantime, as to anticipate and transition any projects for the next release where the bug should be addressed.
Thanks,
TBM
I would also like to know if the FDSP feeback is supported now in SigmaStudio or if the ADAU1787 support for this is in SS+
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