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design digital filter

i am working arm mcp2300 with lpc2368 processor. i want to design a digital filter like a lowpass,high pass,notch filter.so give me some idea about digital filter design using lpc2368 and also give some example of filter

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  • Trolling for some source code?

    There are many DSP forums where you can find this information.

  • There are many types of digital filters. There are many programs to help you with your specific design.

    For example, this is something I modified for my own use to help me with my designs. You can do the same:

    Rectangular Window Designed FIR Filter
    
    Filter Type: LP
    Passband: 0 to 1000 Hz
    Order(Width): 40 Tap(s)
    Transition Band: 184 Hz
    Stopband Attenuation: 21 dB
    
    A[0] = -0.01461642
    A[1] = -0.008595516
    A[2] = 0.00436906
    A[3] = 0.01565962
    A[4] = 0.01685484
    A[5] = 0.005775972
    A[6] = -0.01116543
    A[7] = -0.0223975
    A[8] = -0.01872126
    A[9] = -0.0002524579
    A[10] = 0.02210215
    A[11] = 0.03244082
    A[12] = 0.02012452
    A[13] = -0.01161655
    A[14] = -0.04456532
    A[15] = -0.05370933
    A[16] = -0.02099536
    A[17] = 0.0528877
    A[18] = 0.1457902
    A[19] = 0.2228482
    A[20] = 0.2527095
    A[21] = 0.2228482
    A[22] = 0.1457902
    A[23] = 0.0528877
    A[24] = -0.02099536
    A[25] = -0.05370933
    A[26] = -0.04456532
    A[27] = -0.01161655
    A[28] = 0.02012452
    A[29] = 0.03244082
    A[30] = 0.02210215
    A[31] = -0.0002524579
    A[32] = -0.01872126
    A[33] = -0.0223975
    A[34] = -0.01116543
    A[35] = 0.005775972
    A[36] = 0.01685484
    A[37] = 0.01565962
    A[38] = 0.00436906
    A[39] = -0.008595516
    A[40] = -0.01578999
    
    float FIR(input_sample)
    {
       /* Shift filter_buffer samples */
       for (j = NUM_COEFFS; j > 0; j--)
       {
          filter_buffer[j] = filter_buffer[j - 1];
       }
       filter_buffer[0] = input_sample;
    
       /* Convolve filter_buffer with filter_coeffs */
       output = 0;
       for (j = 0; j < NUM_COEFFS; j++)
       {
          output += filter_buffer[j] * filter_coeff[j];
       }
    
       return(output)
    }
    
    

  • Before you can start any design on any specific processor, you need an understanding of the general principles.

    You have already been give two links for that - have you looked at them?

    Specific details of the particular board and processor that you are using will be found in the Documentation for those products...

    Here's some more study for you:

    http://www.keil.com/books/

  • i want to design high pass filter with 0.05 HZ cutoff frequincy.this filter usig in biomedical signal processing with ecg machine.

  • i want to design high pass filter with 0.05 HZ cutoff frequincy.this filter usig in biomedical signal processing with ecg machine.

    Ah, those are tricky. Especially if your sampling rate is 500 Hz or higher and you're stuck with 32-bit arithmetics.

  • We use these machines in our socialized healthcare system. Cuts down on the need for 'death panels'.

  • which cutoff frequency use in high pass filter?