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The General Purpose and Text Entry blocks have multiple options for biquad filters based on Robert Bristow-Johnson's work in this field.
For all of the above filters, the coefficients are divided by a0, normalizing them and making a0 = 1 so that only 5 coefficients must be stored. In the actual implementation on the DSP, when the coefficients are stored in parameter RAM, a1 and a2 need to be inverted. This is done automatically, in software, before the parameters are written to memory.