Safeloading coefficients

Hi Miguel,

To update parameters in real time while avoiding pop and click noises on the output you should use the safeload mechanism. The safeload mechanism enables the SigmaDSP core to load new parameters into RAM while guaranteeing that the parameters are not in use. This prevents an undesirable condition where an instruction could execute with a mix of old and new parameters. The downside of using safeload is that you can only update 5 parameters (as most standard signal processing algorithms have five parameters or less) per audio frame. Block writes can occur sequentially but will cause pops and clicks on the output.

Yes, you can always use safeload if you so desire but it will be slower as only one set of parameters can be written per audio frame. If you need to write a lot of parameters then it may be better to either stop the SigmaDSP and perform block writes or mute the outputs and perform the parameter block writes.

Best Rgds,

Alan

Thank you Alan:

This is great thank you. In short, I can use the Safeload Mechanism always with the condition that my uC code would write at a lower speed than one input sample. This would mean that if I run @ 44.1kHz my uC write should need to be longer than that.

Also, for biquad filters were most of the cases I use 5 coefficients, the current safeload mechanism would work fine but when I use longer FIR type of filter, I must split them up in chunks of 5 if I need to update them.

I would prefer not to mute my system at any point since this would be a bit undesirable for my audio application.

Thank you

Miguel

>> corrected a typo loner -> longer and mechanim -> mechanism