You are reading a single comment by @Gordon and its replies.
Click here to read the full conversation.
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.
@Gordon
Just to add - looks like some displays have a proper power supply on them, and some use a charge pump.
The previous code handled displays with a proper power supply, and it didn't set up the charge pump. It's why some displays might not have worked.