I’m trying to use Arduino 1.8.15 with an Arduino Mega (ATmega2560) and an ISP-Programmer on Linux.
Programmer works fine with standalone
avrdude -P /dev/ttyACM0 -p m2560 -c avrisp2, so I set Tools→Programmer and Tools→Port accordingly. I verified that values were written correctly to ~/.arduino15/preferences.txt.
Unfortunately, when I hit ›Sketch→Upload Using Programmer‹ or ›Tools→Burn Bootloader‹ Arduino keeps to call avrdude with
-cstk500v2 – which fails unsurprisingly.
What might I have missed?