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ADAU1442 - parameter ram position and Selfboot EEprom?

Question asked by mbente on Nov 16, 2010
Latest reply on Nov 23, 2010 by mbente



I have build an ADAU1442 AudioSystem, the hardware is working fine with SigmaStudio and Selboot from a EEPROM.

In my structure i have 5 IIR Filter in series for every channel of audiodata. I have to change the coefficents of every IIR Filter with an external Microcontroller.

The coefficents have to be generated with SigmaStudio or Matlab. And store it in the MCU. That isn't a problem...


I want to make the Bootsequence like this


on power up

    -> ADAU Selfboot from EEPROM


to change the parameters

    -> MCU stores new parameters to EEPROM

    -> MCU stores new parameters to the ADAU's Parameter RAM (adresses of the coefficents are known)


is this the best way?


I think about it,

     - because of an powerloss the system boots with his last parameter

     - The MCU can get the actual state of the filters from the EEprom.

     - There is no Writebackfeature on the ADAU1442 so the MCU have to do the job


My Problem is to define the parameter position in the EEPROM Data. Is there any Information about it? Any change in SigmaStudio like delete a trace and put it on THE SAME position will change the position of the parameter's in EEPROM.hex!


I don't know how i will solve the Problem to find the correct position of the parameter data in the EEPROM.


Anywhere is there any Information about the position in the P-Ram to the Filter number. Is this variable? I see in Sigma Studio that for example filter0 has sometimes adresses in RAM from 0x08 to 0x12 and on any change and new compile they can be on an other adressrange?!



Thank you for your help.


Greets Moritz Bente