Espruino JavaScript interpreter for low power ARM Microcontrollers

Gordon writes in about Espruino, a JavaScript interpreter for Microcontrollers:

Espruino is a JavaScript Interpreter for low power ARM Microcontrollers (MCUs)

All you need is a serial terminal, and you can program interactively with high level language features like Maps, Objects, and Garbage Collection.

Espruino is currently available for OLIMEXINO-STM32, LeafLabs Maple, Many ‘HY’ branded 2.4/2.8/3.2″ LCD touchscreen modules, STM32F3Discovery, STM32VLDiscovery and STM32F4Discovery boards

Via the contact form.

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  1. No, it’s not yet (all the code on the website is though)… Espruino is still free to use – with a small charge IF you want to save your code to flash. I always wanted to make Espruino available for a wide variety of boards – so you could take that board that’s gathering dust and program it in a nice easy way. I’m not after making loads of money but I kind of wanted to be able to support users and improve Espruino without doing it all in my free time. The problem has been that if I Open Source it I can’t make anything from it directly any more unless I intentionally cripple the Open Source version. I tried donations for a while and got nothing – and nobody wants to pay even a tiny licence fee (I’ve asked a LOT of manufacturers) for selling Espruino on hardware when anyone can buy cheap boards and then put Espruino on them for free.

    Basically people are willing to pay for OSHW but they’re not for OSSW to go on it. So I’m in the process of creating a board specifically for Espruino – which will be OSHW, and I’m hoping to head to KickStarter with it in a month or two. I’ll then tidy up the code and release everything Open Source, which I hope will keep everyone happy – and I’m hoping that some people will port it over to new platforms – like the Due and Stellaris.

    1. It does seem to a be a problem in the open source world, no one wants to pay for the software meaning people can’t afford to work on it. Unless you have an understanding wife and no kids!

      The only way of funding it seems to be linking it to physical items or a service

      Good luck with your future KickStarter, I tried and failed but learnt a lot in the process!

      1. Thanks for the support – often I get the feeling from comments that people assume I’m evil for trying to find a way to do what I love full-time. What did you try KickStarting?

        Open Source Software works great when biggish companies are using it and paying for support and improvements – and it benefits everyone. It just seems like a hard slog if you’re not making something for businesses – as individual users won’t generally pay for support.

        I do want to Open Source it, but I feel it’s best for everyone if I can do so in a way that allows me to continue to work on it and to integrate, test and vet pull requests properly.

  2. ARM CPUs can execute from RAM, which means that a JIT is possible, making this interpreter just the first of many steps. I wish the author best of luck in continuing this effort. Good start :)

  3. 2 Gordon Williams:

    “Open Source Software works great when biggish companies are using it and paying for support and improvements – and it benefits everyone. It just seems like a hard slog if you’re not making something for businesses”

    – so, you understand it all: noone’s going to pay for Espruino, because JavaScript on low power ARM Microcontrollers is a joke (not the way to get low power consumption for sure ;-) ). (That doesn’t mean it’s not cool – oh, it is!)

    Solution is obvious though: 1) Make a social contract between yourself and the world that if you get paid by doing *an* opensource, you will hack on Espruino too. 2) Find a job which deals with opensource JavaScript, *or* opensource ARM (both doable).

    As anyone else says, best of luck with Kickstarter, but after thinking of that way myself, I figured that it’s a way to convert capturing and time-consuming hobby into *very expensive* hobby. Why not just enjoy your hobby as a hobby without burdening oneself with more responsibilities?

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