For a project I use a Due to sample a signal, apply a biquad filter and output the result to a DAC.
From https://en.wikipedia.org/wiki/Digital_biquad_filter I got the general formula;
(b0 + b1*z^-1 + b2*z^-2) / (a0 + a1*z^-1 + a2*z^-2)
I calculated the coefficients for a lowpass filter and got it working on a dedicated DSP.
However I do not understand how to apply this filter on an Arduino. Is there some way to 'multiply' the input with the filter to get the output, or how does that work?