IIR filter on stm32f4dicovery board with MATLAB[Solved]

[Rashad Shubita]

Hi all,

I am developing an IIR filter with CMSIS-DSP but it gives wrong output data mostly (inf) , even that the data is correctly acquired, I test FFT and it's work great!

Any help will be appreciated.

Thanks in advance.

[Rashad Shubita]

[Solved]

[Imen.D]

Hello @Rashad Shubita​ ,

It will be more interesting to let us know how you resolved this issue. It may be helpful for other Community users.

Imen

[Rashad Shubita · Accepted solution]

HI @Imen DAHMEN​ 

I just flip a1 and a2 coefficients sign, just as simple as that! Actually, it took a lot of my time:grinning_face_with_sweat: hope to save other people time 

The same thing in MATLAB and lowa Hills IIR filter designer tool.

 

[gregstm]

Yes. it's always the simple things that will get you (but still take a long time to solve)

[Rashad Shubita]

Yes you are right!