I think you maybe tried to link it - but just wanted to add that the reference at http://www.espruino.com/Reference usually tells you what is and isn't available on different boards. If it doesn't for a board then that's something I could fix if I know about it.
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.
I think you maybe tried to link it - but just wanted to add that the reference at http://www.espruino.com/Reference usually tells you what is and isn't available on different boards. If it doesn't for a board then that's something I could fix if I know about it.