Welcome to the forum, Joe!
You are a bit near at the edge of the chip performance with 1.25Msps of the ADC and 20000+ interrupts per second. I would suggest to control using a logic analyzer and some pins you trigger if your device programming is capable of that speed.
PS: Where in Germany are you located? I live near Bremen.
I'm in Baden-Würtemberg so thats far away plus this is kind of a study for my workplace(im a student) so direct help wouldn't be possible because i'm controlling classified electronics with the controller the code I provided is just some basic testing and calculation.
I already used a logic analyzer for displaying my adc results etc. but I need to be able to evaluate how long the programm needs for calculations and sampling for the study.
So if i got too much interrupts toning down sampling rate of the adc and the trigger-timing would help to be able to properly debug using the creator?
*UPDATE And just for Clarification my only interrupt which has issues is the DMA one ... all other interrupts trigger as they should and even reducing the interrupts to a minimum by just using continious mode and removing the adc_trigger ISR doesnt help either.
Can in the line
adc_conversion[periodeAnz-j+i*periodeAnz] = (((2*adc_i_samples[k])-1024)*NdRI);
at j==0 and i == 50
a write outsides the array happen?
It shouldn't be possible to get into the loop at i=50 since at i=49 the loop increments i at the end of the for loop and then checks if the statement i < sample_pro_periode returns true which at i=50 is not the case so it exits the loop.