Answering some technical FAQs

I thought I’d add a post here to answer some of the common technical questions/comments that are coming up.

All of this information is preliminary, as the design is still being developed.  I plan to continue to edit this page as I get time, so check back again.

Light output?

First of all you should not consider this device as your main room light source, and it possibly isn’t the best task or reading light.  It is more of an mood/ambient and/or notification light.  Update: I’ve taken one of the latest prototypes home, and tested it at night as a bed side lamp.  It is sufficiently bright to read by, nearly the same as my normal 40W lamp, and my wife kept asking me to turn the light off so she could go to sleep!

Full LED power is about 12W, but the light will be highly diffused and emanates from all sides of the cube, so it cannot be easily compared to a standard point light source.  The prototype cubes as shown in the video and photos are not quite as opaque as we had planned, and the individual LED’s on the next prototypes and production unit will hopefully not be as visible – except on the bottom face due to internal stuff, but that does open up other applications…

While I do have access to some photometer/radiometer instruments, I don’t have a way to take or present measurements that would be useful to the average backer, and any measurements are likely to change as we finalise the design.

The Light will be able to integrate with other automated/connected lights, such as LIFX or SmartThings, so the hallway “landing strip” demo in the KS video could actually turn on real house lighting if you have that automated & networked.  Similarly, it could be set up to trigger a network connected audio player for wake up music, triggering louder and louder music until you get of of bed.  :-)

Power consumption?

The internal electronics at idle (and with no LED’s on) should run at somewhere between 0.5W and 1.0W.  It does need to keep WiFi active to be useful.  That is measured at the 5V supply on the prototype electronics (typically about 120mA, or 0.6W), and doesn’t include the efficiency of the external power supply, which hasn’t yet been finalised.

Oh, and yes we will supply an international power plug suited to your location.

What can I run on it?

The unit includes a fully functional ARM based Linux computer, just driving a bunch of LED’s.  It boots ArchLinuxARM off a microSD card.  You can SSH in and install other packages, or even swap the microSD with your own ARM distribution built for the Freescale i.MX233, such as the Olimex OLinuXino which we are basing our design from.

Access to the serial console will be possible for debugging (using a 3.3V logic level adapter like this), as well as the I2C bus (also 3.3V logic level).

The one limitation in terms of what you can run is the memory, which is only 64MB.  We’ve included a swap partition on our prototypes, but it is rarely needed.  We actually managed to do a full kernel recompile on one of the units, but it did require swap and took a couple of days to complete!  I should have plugged a USB hard drive in, but it was a fun test.

Audio / Speaker?

I am planning to add an internal connection for this on the next PCB design, but without any on-board amplifier it isn’t much use except for headphones, powered speakers, or to the more dedicated hardware hacker.  We really do want to focus on this being a light more than anything else, and if we do add audio you should not expect it to be high fidelity.

Battery power?

Update: This feature has now been announced as an upgrade.  For the technical among you, we use 4 x NiMH AA batteries (not included), plus a boost converter to ensure the 5V supply for the CPU & WiFi doesn’t drop below 5V.  There is also a boost converter on the external 5V input to be able to charge the batteries to their full state of nearly 6V via a two stage constant current supply.  Preliminary schematics of all the design including the power management are up now too.

USB charge port?

This was actually one of my first thoughts, and I suggested it to Mark the first time he showed me his idea.  It will require slightly beefier power supply, and the extra connector(s) will ruin the aesthetics.

If you are a hardware hacker, it wouldn’t be too hard to add it yourself – just unplug the USB WiFi and plug in a small hub, moving the WiFi to a hub port.  Not sure if you could squeeze a hub inside at this point.


Not something we have considered.  WiFi provides the necessary connectivity for most use cases.  You could always add a USB hub and BT adapter.


It isn’t our main focus right now, as you could possibly imagine.  But Breton has coded one up, and it will be put onto GitHub soon.

Stretch Goals?

None set in stone as yet, and it is pretty early in the campaign.  Many of the above ideas have been on our list since before launching on Kickstarter, and we are developing a strategy as fast as we can.

18 thoughts on “Answering some technical FAQs

  1. Pingback: Just the FAQs | Hacking Light

  2. Will the hardware configuration (and obviously your business model) be such that you will be selling the computer part without the rest of it?

    Just in case anyone wanted to, say, hook it into some BIG lights, with huge driver boards? (Or, more likely, just have another alternative to the Raspberry Pi ;-)

    • Not sure at this point, but I’d sure like to. Or maybe a variant of the design that is a bit more generic – if we can get a batch produced at the same time at a reasonable price. Of course, you can always just get some of the Olimex boards, which are very cool.

    • Just to further explain why Ethernet (and some other additional connectors) are unlikely to be included

      – the connector and any additional related components add significantly to an already tight BOM cost

      – they would require significant mechanical redesign

      – they damage the aesthetics

      You can of course unplug the USB WiFi, and plug in a USB Ethernet adapter that has Linux drivers. Doesn’t provide PoE support, but that could probably be done with an additional module and some soldering.

      • Actually it looks like Twine is mean for output – via twitter, email, HTTP, etc – rather than input. So it could be configured to access the light via a HTTP request to access any of our open API, or your own custom code.

  3. Bluetooth/A2DP w/speaker would be cool…. Could use for sound distribution w/ mood lighting (relaxing bath lighting etc) – Also – could potentially the tie in w/ DSP plugin – Moodlighting as music eyecandy… (Sync light phasing/colours with signal output)


    • Bluetooth would drive the bill of materials up substantially, hence the cost of the Light. And where would this sound be coming from that it would be distributing? Wouldn’t that be best left with another and dedicated device?

  4. Hi,

    Im trying to understand your project.

    Will I be able to send a light message say from my iphone, when out of home… equivalent to a caress or a gentle Hi all is fine, un intrusive… who ever is home in contact with the light will understand this message? And feel the presence of the message/sender?

    Distance and time will not be an issue i guess since the internet.

    Sounds great and fun, congratulations.

    Greetings from Valle de Bravo in Mexico


  5. Since this site started, back in December, you indicated a 6-month timeline. July is now well less than 6 months away. I really do want you guys to succeed, and I don’t mind waiting, but something doesn’t add up—are you moving the deadline, or revising the calendar :)?

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