how can i do LPF in mikroc pic32?
what code do I need to implement to apply the LPF?

thank youd

 

https://www.acronymfinder.com/LPF.html
?

 

https://www.acronymfinder.com/LPF.html
?

i mean low pass filter code...

 

for a single pole filter:
Output += (Input-Output)/factor;
is the simplest possible.

 

for a single pole filter:
Output += (Input-Output)/factor;
is the simplest possible.

I need to do this filter for sin wave with noise

 

What frequency sine-wave? What is the sampling rate? What does the noise consist of? and what frequency is it?

 

What frequency sine-wave? What is the sampling rate? What does the noise consist of? and what frequency is it?

there is all the details

 

Not sure if these documents will help.
https://onlinedocs.microchip.com/pr...tml?GUID-6841A809-DEAD-43E2-816F-D937BD53DF46
https://forum.mikroe.com/viewtopic.php?t=55776

 

View attachment 326929

there is all the details

And what are you trying to achieve?

 

And what are you trying to achieve?

I want to received filtered signal after low pass filter .
Do you know how to do it?

 

What order filter do you need (.i.e. how fast a rolloff above the filter corner frequency)?

 

What order filter do you need (.i.e. how fast a rolloff above the filter corner frequency)?

I don’t know already used in Matlab, are you have some examples how to choose that ?

 

I don’t know already used in Matlab, are you have some examples how to choose that ?

As you have added broadband noise, there will always be noise on the filtered signal, because the noise appears at every frequency.

 

As you have added broadband noise, there will always be noise on the filtered signal, because the noise appears at every frequency.

in matlab I got this:



so i think that i some pic32 code of low pass filter i can do something like that

 

in matlab I got this:
View attachment 326935


so i think that i some pic32 code of low pass filter i can do something like that

The code in post #4 will do something like that

 

The code in post #4 will do something like that

are you sure just this line will be enough for that?>

 

are you sure just this line will be enough for that?>

Yes - that's a single pole IIR filter. I use it all the time to remove noise from ADC inputs.
It can be implemented in three instructions in ARM code, so it executes in 62ns on a 48MHz clock.

 

Yes - that's a single pole IIR filter. I use it all the time to remove noise from ADC inputs.
It can be implemented in three instructions in ARM code, so it executes in 62ns on a 48MHz clock.

I have clock of 50 MHZ
are you can show me how to implement this filter to my code? how to do it?

 

Yes - that's a single pole IIR filter. I use it all the time to remove noise from ADC inputs.
It can be implemented in three instructions in ARM code, so it executes in 62ns on a 48MHz clock.

I see this fir code but its not working for me:

void CalculateFloatFilterCoefficients()
  {
   for (k = 0; k< (FILTER_ORDER +1); k++)
   {
    floatFilterCoefficient[k] = 1.0/(FILTER_ORDER+1);
   }
  }
 
  void ConvertCoefficients()
  {
   for (k = 0; k< (FILTER_ORDER +1); k++)
   {
    Q15_Ftoi( floatFilterCoefficient[k], &Q15_FilterCoefficient[k]);
   }
  }
 

void DoFIRfiltration()
  {
   for (k=0; k< (SIGNAL_LENGTH) ; k++)
   {
    outputData[k] = FIR_Radix(Q15_FilterCoefficient, FILTER_ORDER+1,signal, SIGNAL_LENGTH,k);
   }
  }

moderators note: added code tags

 

I have clock of 50 MHZ
are you can show me how to implement this filter to my code? how to do it?

Your input signal is noisy_sine_wave.
so
filtered_sine_wave += (noisy_sine_wave-filtered_sine_wave)/factor

factor sets the frequency response

By the way, FIR filtering takes an awful lot of computation - for whatever number of coefficients you have you have to do that many MAC instructions every cycle.