AnsweredAssumed Answered

Need help with getting PCM data from AD1836 on BF561

Question asked by Fos on Jan 7, 2010
Latest reply on Jan 15, 2010 by TomA

Hi all,


I'm currently working on a project which is to create an MPEG-4 (audio/video) encoder on a Blackfin. For starters, I'm using the ADSP-BF561 EZ-KIT LITE, equipped with an AD1836AAS audio codec chip. The video encoder part is finished and works well, the audio encoder on the other hand not.


The MPEG-4 audio encoder is based on the HE-AACv2 encoder software module, provided by ADI. The provided documentation describes the use of the software module, along with it's compatibility with a BF561. However, it seems the code example in the BF561 folder is actually meant for a BF527, BF533 or a BF548. Given the fact the BF533 and the BF561 are both equipped with an AD1836 audio codec, i was kind of hoping it wouldn't be that difficult to make it work on a BF561.


I've started to analyse the code and eventually used bits and pieces of code for my encoder. After including loads of header files, before i could finally compile my code, the program is unable to initialize the AD1836 codec. Specially the function EnableCodecDataflow, discribed in the usb_audio_6ch_services.c which returns the following:


- Failed to disable audio codec dataflow, Error Code: 0x40000007

- Enable Stream Mode Failed

- Adi_dec_Read Failed

- Adi_dec_Write Failed

- Failed to enable AD1836 dataflow, Error Code 0x40000007


I'm not sure what is wrong with my code, but I could really use some help by now.


Since the software module requires a PCM signal as an input, I'm supposed to configure the audio codec in such a way it will give me the PCM signal. But for some reason, there's pretty much no documentation which describes the working.


So could someone explain to me which step I need to take and how I need to configure the BF561


Thanks in advance, your help is appreciated


Erik Vossers