Tone control implementation

Hello markatucla,

Thanks for including your project. It is always so helpful.

First I want to mention that the stimulus and probe feature will not work with an indexed filter because SigmaStudio has no idea what filter is active in the DSP. The probe display is all calculated in SigmaStudio in the PC using the coefficients it knows about. You actually do not need the hardware for this to work which is about the only thing that works that way with the SigmaDSPs. So SigmaStudio does not know what filter is selected. Also, for others who might be using the Sigma300/350 parts, many of those filters the coefficients are calculated in the DSP not in SigmaStudio do the probe will not work there either. 

You are having an issue with number formats. You need to send an integer format to the filter index. You are sending a HUGE number. The number coming into the control pin is used as a pointer offset so it needs to be an integer. 

Here is an example project:

ADAU1701 AUXADC Index Selectable Filter.dspproj

Then I can suggest you watch some of my videos on a few different subjects that kind of got you. 

Here is a list:

(+) ADAU1701 Capture Window, Params Tab and Sequencer window - Videos Published - Video Annex - EngineerZone (analog.com)

AUX ADCs (youtube.com)

This one is about Readbacks:

https://youtu.be/GDLhk1E-98A

Thanks,

Dave T

Thank you. That clarified everything, and I have a working system. I had assumed that the indexed filter would have accepted a fixed DC value in my tests and therefore would have passed the Stimulus. The fact that I saw nothing with the Probe threw me off. 

     Hello all,

     More about the Stimulus-Probe tool's capabilities and limitations.

     Best regards,

     Bob