MorseKey.ino

#include <AStar32U4Prime.h>
const char key = '.';
Pushbutton buttonD(0);

void setup() {
  Keyboard.begin();
}

void loop() {
  if (buttonD.getSingleDebouncedPress()) { Keyboard.press(key); }
  if (!buttonD.isPressed()) { Keyboard.release(key); }
}