AnsweredAssumed Answered

Updating coefficients in IIR accelerator

Question asked by Probbie on Jan 4, 2013
Latest reply on Jan 31, 2017 by pereira

Hello Folks

I am trying to get to grips with the IIR accelerator on the ADSP-21488 DSP.

I am loading the initial coefficients into the accelerator when initialising the accelerator, by allowing the TCB to point at the source of the coefficients.

However, I need to be able to change the filter coefficients 'live', while the product is being 'listened to'.

So, two questions if I may:

  1. The examples assume that the coefficients are static and are not changed after initialistion. What is the standard accepted way to change the coefficients - what is used to trigger the loading of revised coefficients?
  2. Since the state (Dk) values are loaded at the same time as the coefficients, I am concerned that 0's in the coefficient source memory will be written into the IIR's live Dk's and wreck the state, causing disturbance to the audio.

Any help on this would be very much appreciated.

Many thanks