Hi,

I refer the "FilterMathFilterCalculations.pdf". But there are no equations for 2 order low shelf and high shelf filter.

Is there any document about that, please?

Best Regards,

Duke

Hi,

I refer the "FilterMathFilterCalculations.pdf". But there are no equations for 2 order low shelf and high shelf filter.

Is there any document about that, please?

Best Regards,

Duke

Hi Duke,

Please refer to the below page for Low-Shelf and High-Shelf filter coefficient computation.

http://wiki.analog.com/resources/tools-software/sigmastudio/toolbox/Filters/General2ndorder

Best Regards,

John

Thanks John,

I have another question. If I want to design a GUI on PC and it can control the EQ in the DSP.

Should I use the EQ equation to calculate the coefficients then package it to SPI protocol. Then send it to dsp.

Or I should set all the possible 5 coefficients to arrays and build in memory.

And you know the EQ's equation parameter have Q, fc, boost, gain. And they are dependent. I think it is too many data.

If I want to use the equation to calculate the coefficients. How can I translate the data to the format 32bits like

the SigmaStudio send to sharc?

Best Regards,

Duke

Hi Duke

Based on your requirement and use-case, you may decide one of the below options.

- Have GUI controls for 'Gain', 'Q', 'Fc', 'Boost' etc in your GUI application. Compute the filter coefficients using the formula. Pack the computed coefficients within the SPI protocol and send to DSP. The coefficients are expected to be in IEEE Floating point format. Once you compute the coefficients on the host application, assign them to float variables. Extract the bytes from the variables and use these byte data to create the packet.
- Second option is to have different sets of pre-defined coefficients computed and kept in different arrays in the host GUI application. Choose one of them based on the user selection and send to the DSP.

Regards,

John

Hi Duke,

Please refer to the below page for Low-Shelf and High-Shelf filter coefficient computation.

http://wiki.analog.com/resources/tools-software/sigmastudio/toolbox/Filters/General2ndorder

Best Regards,

John