[SHARING] Filter coeficents online calculator with sample code for C++, C#, MicroPython and Arduino Sketch

Hello Rocha,

Thanks for the link to this resource.

Dave T

Hello, I still have many questions. For example, I used to use 1452 spi to control. If the first write register address is 0, then it is write. If it is 1, then it is read.

void SIGMA_WRITE_REGISTER_BLOCK(byte devAddress, int address, int length, byte pData[]) {

#if USE_SPI    // Start of function for SPI write
    // Assert SPI slave select line
    digitalWrite(DSP_SS_PIN, LOW);        // Assert SPI slave select line (active low)
    SPI.beginTransaction(settingsA);      // Initialize SPI
    SPI.transfer(0x0);                    // SPI read address + read/!write bit  0 or 1 read or write
    SPI.transfer(address >> 8);           // High byte of address
    SPI.transfer(address & 0xff);         // Low byte of address
    for (int i = 0; i < length; i++) {    // For each data byte in the packet...
        SPI.transfer(pData[i]);           // Write the data byte to the DSP
    }
    SPI.endTransaction();              // Release the SPI bus
    digitalWrite(DSP_SS_PIN, HIGH);    // Pull up the slave select line
// End of function for SPI write
#else     // Start of function for I2C write

Now I use i2c to control 1701. I don't know the read/write address. The method is different from that of SPI。

Also, I need to calculate the C language code of the filter. Some parameters of the code downloaded from the online calculation are undefined, and I don't know how to define values. I want to get the code for calculating the filter. There is no such code in the routine you provided for download.

res = coeficents( family, FILTER_2ND_BYPASS, fs, 100, 1.41, 1, 1 );
writeToDspSafeload( address, (unsigned char*)&amp;res, sizeof(res) );

Amp and res are not defined, so I don't know how to define them.

for (int i = 0; i < sizeof(coeficents_t); i++) {
if ( i > 0 && (i+1) % 4 == 0 ) {
Serial.printf("%02X\r\n", (unsigned int)((uint8_t*)&coeficents)[i]);
} else {
Serial.printf("%02X ", (unsigned int)((uint8_t*)&coeficents)[i]);
}
}

Lt is also undefined

Also, how does Crossover Filter calculate? Filter TYpe: How is Linkwitz Filey 24 or Butterworth24 or Bessel 18 calculated?

Just what i was looking for, together with Bob's spreadsheets i was able to create my code for the esp32, however there seems to be a bug in the peaking filter calculations, changing it to the formulas in the spreadsheet worked