The is a legendary open-source, Arduino-based Morse code keyer developed by Anthony Good (K3NG). It provides features that easily rival high-end commercial hardware.
If you cannot find a repack that matches your exact configuration, build your own using: k3ng keyer schematic repack
So, before you download the 7000-line .ino file and panic, find a repack. Print it out. Grab your Nano, a handful of resistors, and a MOSFET. And get ready to send your first perfect “CQ” — knowing that every dit and dah is guided by a schematic that finally makes sense. The is a legendary open-source, Arduino-based Morse code