Welcome in the forum, Martin!
The filter block delivers signed numbers in the range of -128 to +127, the DAC only accepts positive numbers in the range 0 to 255. This is the reason why in the original project 128 was added to the filter result. Since this cannot be done with the DMA component you will have to stay with the interrupt driven solution.
PS Where in Germany are you located? I live near Bremen
Good morning Bob,
The idea with unsigned and signed numbers was one of my first thoughts.
But it cannot be the answer, because than the video of cypress with the replacement of the interrupt with the dma would be a fake...
PS: I'm living in Soest ( between Dortmund & Padaborn )
Which video (link please) are you referring to?
Wasn't there a "Konrad Zuse Museum" in / near Paderborn?
You can find it in die video library of cypress for the psoc 5lp... or on youtube with better resolution
Maybe he forgot something to mention in the video...
Never heard, that such a museum is in my near...
Is it possible to use an "Xor" to add an 1000 0000 to the output of the filter ?
I would suggest to contact the author (Todd Dust) directly. Create a support case: At top of this page select "Design Support -> Create a Support Case" and describe your problem, mention Todd, the video etc..
Museum is part of the Nixdorf Museum, just googeld.