Tessel: A microcontroller that runs JavaScript

by darkmethod • 12 years ago

121 88 12 years ago

johnpmayer• 12 years ago

This is great. I have some small background in real time embedded systems, but I think that 99% of the "internet of things" need not be written in low-level C. I'll probably pick this up...

...however, I do hope that they can bring down the price for future models. $100 is a bit steep for a hobby project to control my AC. For now, I understand that the premuim is rewarding the software effort.

Timmmmbob• 12 years ago

You don't have to write in low-level C. You can write in high level C++, which is vastly preferable to javascript! Or hell, why not write in Lua! It's what this apparently transpiles to, and is much nicer.

The only reason javascript became popular is because it was the only option on the web. Why does that mean we would want to use it when we have better options?

bsder2• 12 years ago

You can write in high level C++, which is vastly preferable to javascript!

First, C++ compilers are not available everywhere. Second, C++ compilers do not always implement all corners of the language on embedded systems. Third, C++ is better than Javascript? That's going to take some explanation.

Or hell, why not write in Lua!

Lua has it's own share of "Wat". 1-based indexing when a non-trivial amount of your stuff needs to interoperate with C is a big one. In addition, Lua is nicely configurable--read, "Every Lua implements a different set of modules."

The only reason javascript became popular is because it was the only option on the web.

It's popular to hate on Javascript, but Javascript isn't that bad. Go back and take a look at Javascript in the Netscape 2.0 and Netscape 3.0 timeframe. It's a fairly straightforward, minimal language.

Now, all that having been said, this isn't exactly impressive. A 180MHz ARM with 32MB of flash and 32MB of RAM is not a small processor. With that level of power, there are lots of options.

If this were running on an 50MHz M0 with 256K flash and 16K RAM, it would be impressive.

twerquie• 12 years ago

For the same reasons you're writing in English.

HeyLaughingBoy• 12 years ago

Beaglebone is cheaper and already runs a version of node.js that has extensions to do digital/analog I/O

dzhiurgis• 12 years ago

STM32 + espruino.

Lost my interest the first day. Couldnt manage to make it run.

pjc502• 12 years ago

Arguably should not be written in low level C, but something safer, lest it become the Internet of Unfixable Botnets.

GuiA• 12 years ago

$100 for something vastly inferior to a Raspberry Pi, Beaglebone, etc. that cost 1/2 to 1/3 of that. What am I missing here?

eplanit• 12 years ago

Equally as ill-conceived and/or misdirected as other "language du jour"-specific chips of times past?

http://en.wikipedia.org/wiki/PicoJava

http://en.wikipedia.org/wiki/Jazelle

pjc502• 12 years ago

Jazelle still exists in newer ARMs; ARM shot its own foot off by keeping it closed, so its use is limited to a few corporates.

noodle5• 12 years ago

Lower barrier of entry for people interested in playing around with hardware development. No breadboards and wires, only pluggable modules. Javascript instead of C.

kasbah• 12 years ago

No Linux, which can be an advantage or a disadvantage depending on whom you talk to.

joshvm2• 12 years ago

I think for many people cost is the most important factor. People who bought the RPi did so because it was so cheap that it was practically an impulse purchase.

Disregarding the actual device price, the other issue here is the expensive module pricing. Let's face it, if you're buying this because you want to do things the simple way then you're going to be buying modules. Ambient light + MicroSD card? That'll be $50 please. Too many electronics outfits shaft consumers like this and too many electronics hobbyists put up with it.

EpicEng3• 12 years ago

So...people who want to play around with hardware development without actually learning anything about hardware development? How is that helpful? Why not just learn what you need to learn and do it right the first time?

retroencabulato• 12 years ago

I really don't see how that homepage example is any simpler than Arduino.

http://playground.arduino.cc/ComponentLib/Servo

aikah• 12 years ago

Tessel is marketed as a "micro-controller" while the PI as a "micro-computer".

Javascript marketing aside,it would be interesting to know if one can reproduce all Tessel capabilites with a Pi + extensions.

I dont think the "but it runs nodejs modules!" matter that much,if you're going to write for embedded devices,you need to go low level and seek optimizations like crazy.The stuff has like 32MB of ram,you cant do much in javascript+nodejs with that.AFAIK it doesnt even run a javascript engine,but translate the code to LUA.

sprobertson2• 12 years ago

it would be interesting to know if one can reproduce all Tessel capabilites with a Pi + extensions.

You can, I've had a Node-on-Pi based home automation system running for a few months now. It looks like Tessel's main advantage is the plug & play nature of their modules.

dkersten4• 12 years ago

Tessel is marketed as a "micro-controller" while the PI as a "micro-computer"

Its funny when a micro-controller is more expensive than a micro-computer... :(

mschuster915• 12 years ago

It has WiFi, which requires FCC testing for the US market as well as compliance certificates for the European area. These certifications and checks are f...ing costly.

RPi/Arduino in contrast only have wired or no networking, thus eliminating a huge part of the upfront costs (e.g. in Europe you then only need a CE certificate, which you can either issue without testing and be liable if your module doesn't meet the standards, or you get an ESD/EMR test for a couple thousand bucks).

dguaraglia• 12 years ago

Good point on the Wi-Fi. I guess that explains the cost, but it doesn't explain why you'd choose it over a Raspberry Pi. You can buy a Wi-Fi USB dongle for like 5 bucks on Amazon.

SpikedCola• 12 years ago

You only need to undergo FCC testing if the module you use is not already certified. You can buy "FCC-approved" modules that are "ready to sell".

I ran into something similar with BT4.0 modules - had to convince the client that a $3 module, while cheap up front, couldn't be sold without spending $$$ on certification. Eventually they went with a $7 one.

foxylad• 12 years ago

Yes, but the Electric Imp has wifi built in for $30.

Ironically it uses the Squirrel language to program it, which I think was a mistake - I found it very unproductive.

Sanddancer• 12 years ago

The base Arduino doesn't have networking. However, there are models, like the Yun, that do have wifi and/or ethernet and are less than the cost of the Tessel.

rememberlenny• 12 years ago

I won a Tessel at JSConf this year and love it.

Are there ways to make our own module attachments? The $50 parts seem a bit steep.

kam• 12 years ago

Yes. The module ports are documented here: https://github.com/tessel/hardware/blob/master/tessel-hardwa... and the JS APIs for using them here: https://tessel.io/docs/hardwareAPI

VLM• 12 years ago

My advice is the wrong tagline is up. If you want an embedded device running JS or higher level than C anyway, you toss in a raspi with much better hardware specs for much less money.

The secret sauce appears to be (at a glance) great software support (edited to add, I'm talking about "high level bindings" like JS... there's plenty of C for arduino, not nearly as much non-C) for a bunch of off the shelf compatible debugged plugin hardware. Also deeply buried in the docs section it appears to draw a Lot less power than a pi when doin "stuff". Of course if you want to blink a LED I think a PIC 10F220 might just slightly have you beat by approximately six orders of magnitude (no kidding, well 4 to 7 depending on blah). Anyway that kind of stuff should be the primary advertising focus, or at least thats what I found interesting.

I'm fuzzy on the "how easy is getting started" part, at least only after five minutes. Not being clear means it must be as bad as gearing up for FPGA work (just kidding I'm sure its not that bad). If its good, this might be an additional secret sauce. Here's a 60 second video from opening box to blinking LED (or, whatever)

At least that was the first five minutes impression from a hardware guy who knows the market. And I've now spent more time typing and thinking than I spent looking.

eudox• 12 years ago

You win, please, just stop the pain.

angersock• 12 years ago

Javascript: the embedded parts.

mtdewcmu3• 12 years ago

Learn Javascript the Hardware Way

pling• 12 years ago

As someone who does a bit of embedded stuff here and there (professionally), this.

I cannot fathom why anyone would even poke this with a stick other than to appease the maker crowd who to be honest scare the shit out of me. And the price. Kill me now.

batmansbelt2• 12 years ago

Espruino is a similar device (without the cool plugins though, so expect to use a soldering iron). Much cheaper too.

pmontra• 12 years ago

I got one and I'm starting to experiment. I discovered that soldering can be a problem. First, I had to buy a solder. Second, physics is merciless and a mistake can toast your card (didn't happened to me yet) vs the run-fail-debug loop we're used to in sw development.

Anyway, some hw modules have been tested with Espruino and the web site explains how to use them. My understanding is that you can plug almost anything into it, you just (!) have to know its specs and how to wire it to the board.

batmansbelt2• 12 years ago

Yep, lots of good tutorials, and the creator of the board is quite helpful on email.

goodbyegti• 12 years ago

It's absurdly expensive, even more so the modules. Looking at the BT module, the BLE112 can be purchased for $15 in quantities of 1. So you pay $35 for a small PCB, some pin headers and probably a wrapper around a UART.

mschuster915• 12 years ago

As written above, everything related to radio has huge upfront costs in certifications. These costs are once-applicable, so if you're making a million-unit BT dongle, then the certification costs per device are fractions of cents. Here with thousand-unit series, the cost per device is massively higher.

asdfs• 12 years ago

Isn't the BLE112 already certified? Or does integrating it into a product require you to get the entire product certified?

LandoCalrissian• 12 years ago

You can kind of achieve the same results with an Arduino board and https://github.com/rwaldron/johnny-five, but you do have to have a computer connected. I think you could probably hook up a raspberryPi with a usb network adapter and an Arduino for the for the same or less cost than the main unit.

Still interesting all the same, if they can get the cost down it would open the micro controller world up to a completely new group of people.

justincormack3• 12 years ago

Actually, a microcontroller that runs Lua. They released the source for the JavaScript to Lua compiler today https://github.com/tessel/colony-compiler

eurleif• 12 years ago

I wonder if this can be used for redis scripting. I bet a lot of people writing node.js apps would like to be able to write redis scripts in JS.

anonymoushn2• 12 years ago

I wonder if you can run code without going through the transpiler. Then you could program it in a sane language.

sdegutis• 12 years ago

That's pretty awesome. I love Lua lately, for its simplicity both in design and implementation, and it's great to see that I can use it in an MCU! That said, it's pretty dumb that it has to have a JS transpiler in order to get popular.

anonymoushn2• 12 years ago

Apparently you cannot run code without using the transpiler, but it is planned.

They also mention that the API will be awkward to use from Lua, but it's probably pretty easy to fix this.

http://forums.tessel.io/t/running-lua-on-tessel/91

justincormack3• 12 years ago

Lua has actually had a microcontroller project for years see http://www.eluaproject.net/ but without the nice slick deployment that tessel has.

bruce_one• 12 years ago

It could be a really interesting tool for porting (some) javascript npm modules to luvit (a nodejs reimplementation with lua instead of js) as well :-)

Just seems like an interesting way to bolster the ecosystem :-)

johnohara• 12 years ago

Device looks to be based on an NXP LPC1830FET180 microcontroller which uses an ARM Cortex-M3 processor at 180MHz.

http://www.nxp.com/products/microcontrollers/cortex_m3/LPC18...

The product page seems to indicate it does a more than run JavaScript.

dkersten4• 12 years ago

It doesn't run javascript (not natively). It runs just like every other ARM microcontroller (so assembly, C, etc).

This device has a lua interpreter running as its firmware (coded in C, it looks like) and these guys wrote a javascript to lua compiler.

So it runs javascript by compiling it to lua bytecode and then intrepreting it in a C-based intrepreter.

habosa• 12 years ago

Relevant: https://xkcd.com/801

ptk921• 12 years ago

In their code snippet, it seems that position is not defined for the first loop and would throw a ReferenceError.

refrigerator• 12 years ago

How does this compare to http://www.espruino.com/?

cobookman• 12 years ago

I wonder how the timing on the micro-controller is. Is the JavaScript still async? While JavaScript +/-10ms is fine on a computer, when messing with signals that really limits you. Mind you this could be overcome by adding some flag before the code to specify it to be run synchronously...or something like that.

rtpg• 12 years ago

nothing in Javascript fundamentally forces IO libraries to be asynchronous, it's just that the domain in which JS is used (Node or Browsers) tend to have a lot of async IO due to networks.

wyager• 12 years ago

nothing in Javascript fundamentally forces IO libraries to be asynchronous

Javascript inherently relies on highly non-deterministic heap allocation, deallocation, and garbage collection. None of these are conducive to real-time IO. You can not make strong guarantees about javascript execution time.

They probably partially get around this by having all the important IO stuff done in C, but then that's not really a javascript microcontroller, is it?

mtdewcmu3• 12 years ago

It's not clear to me exactly how it came about that javascript is asynchronous. My suspicion is that in the earliest days, javascript was single-threaded simply because that made the implementation simpler.

ojanik• 12 years ago

Not enough jQuery!

zwieback• 12 years ago

Really slick looking but way too expensive. Might buy it for $40, tops.

pessimizer2• 12 years ago

When I think microcontroller, I think < $5. I'm not sure what this is supposed to be for - it's almost as expensive as a gumstix board.

mpnordland• 12 years ago

Yes, because we really, really need something else to run JS.

Tessel: A microcontroller that runs JavaScript

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