This project was developed in order to automate repeated inputs required at certain places [e.g. a password for a Windows login].
It allows however to program many different keyboard sequences [including special keys like KEY_RETURN or KEY_F4] and corresponding delays between them. Please refer to SlowKeyboard.h for all supported special keys.
As for the hardware a simple Atmela MEGA 32u4 is required [e.g. Arduino Micro and a Lily TTGO USB were used here] with a button connected between MISO and GND.
In case anyone is interested how I soldered an SMD button into the Lily TTGO USB enclosure and used a LEGO pin as a physical button - don't hesitate to contact me.