AnsweredAssumed Answered

IIR filter crashes on the fly

Question asked by dan_xerx on Dec 10, 2014
Latest reply on Jan 21, 2015 by dan_xerx



My set-up consists of three POTs (Q,F,Boost) connected to the ADC of a uC. The analog values are converted to an index that corresponds to Frequency, Q, or Boost level that are used to calculate the five coefficients inside the uC to an IIR filter. These calculated coefficients are then written to the ADAU1701 IIR filter block via I2C. The coefficients are correct as they are verified and the DSP receives them correctly also verified by an ACK observed from a logic analyzer. Now, the problem is when after writing the first set of coefficients, the filter seems to crash and No change is observed (audio, frequency response curve) thereafter. Can somebody suggest what is wrong? I cannot even think why. Seems like all the written coefficients are correct as verified but there is no change on the response curve even when I change the position of one of the POTs.


YOur input is greatly appreciated.


Thanks in advance,