Sorry, solved.
Oh my god. After altering the NIOSII by adding a PIO the symbol for the block symbol file was altered too, and gets two grid ticks broader. This breaks the connection to the pin defines for the SDTam clock signal.
No error during compilation, maybe a warning?
Without clock, the SDRam do not work properly and so the download fails....
Sorry about this message.
With best regards
Gerhard
