I have solved the problem by defining it manually once again right in my code. Now it recognizes it. However, now I keep receiving numerous errors, because
ReadCodecData , WriteCodecData and Checkforoverrun cannot be defined. I believe these definitions are included in DSP_Config.h which I still cannot find anywhere.
This header file is included into almost every sample Code in the book I've mentioned above. But I cannot find it anywhere =(((((