Asymmetrical FIR
Asymmetrical filters expect the port to contain the full array of coefficients, i.e. coefficient array size is equal to the TP_FIR_LEN.
Symmetrical FIR
In the case of symmetrical filters, only the first half (plus any odd centre tap) need be passed, as the remaining may be derived by symmetry.
The length of the array expected will therefore be
(TP_FIR_LEN+1)/2, e.g. for a filter of length 7, where coeffs are int16:{1, 2, 3, 5, 3, 2, 1}, 4 non-zero tap values, including the centre tap, are expected, i.e. constructor expects an argument:std::array<int16, 4> tapsIn = {1, 2, 3, 5}.