Problem solved. I was using it on the Original board with an external regulator - but I forgot the cap on the output of the regulator.
@DrAzzy started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Problem solved. I was using it on the Original board with an external regulator - but I forgot the cap on the output of the regulator.