Plus the Arduino needs to be plugged into the host computer via USB to function, a rather quaint idea to many in 2018. These were just some of the reasons he decided to port Grbl to the ESP32 board.

Hackaday Podcast 042: Capacitive Earthquakes, GRBL On ESP32, Solenoid Engines, And The TI-99 Space Program 3 Comments by: Mike Szczys November 1, 2019 ...

Universal (ish) Arduino grbl opto-coupler interface also works with logic-level pwm In adding an alternative cutter drive motor (‘spindle’) to an existing cnc machine, an electrically isolated pwm to ...