Hmmm. Did you really put a full stop dot where the komma belong?
My MinimigAGACore is on slot 2. So I changed the program like this:
After copying the program boot.prg into the main directory of the SD card, the boot process still hangs in the yellow window of the TC64V1 start mode. What am I doing wrong?
P.S: If I use your source code with slot = 3, the core from slot 3 starts properly.