Quick Guide ( MAC / Linux)
Install ESP TOOL to ease flashing ESP (yes, that's python too :-) :
First, make sure command line tools are installed on MAC OSX
Download ESPTOOL https://github.com/espressif/esptool
Download M5stack micropython : https://github.com/m5stack/M5Cloud/tree/master/firmwares
Now, upload firmware to ESP via serial port (put your ESP in upload mode -->
That's done, you can connect now via any serial terminal !
Screen / microPython shortcuts: