I've edited the code from EE-365 "Maximising Sampling rate on ADSP-CM40x processor" application note for my needs.
So I only implemented the Timer Init, the ADCC and the DMA configuration to get the ADC working with 2,63 MSPS.
Unfortunately, it doesn't work fine. When I start the debug session the program will never reach the wfi instruction after completing the conversions, except I stop the debug session manually. But in this case I don't get any values from the ADC. I am using the ADSZ-CM403F-EZLITE instead of the 408F. But I suppose that doesn't make a difference!?