This is the VBA Serial Port function set adapted for use with Arduino devices. No other files, licences, payments or registrations are required. Functions can be used directly in Excel cells as ...

ARDUINO CODE This program listens for incoming data on the serial port, assuming that data is formatted as comma-separated values with a minimum length of 16 characters. It reads up to four integer ...

In it, he shows an example of using all three ESP32 UARTs from an Arduino program. He calls the third port “secret” although that’s really a misnomer.

STEP 4 Set the board type and the serial port in the Arduino Programmer. STEP 5 Test the microcontroller by using one of the preloaded programs, called sketches, in the Arduino Programmer.

This feature isn’t exclusive to the Leonoardo, as [Michael] explains in a build he sent in – the lowly Arduino Uno can also serve as a USB HID keyboard with just a firmware update.