Tag Archive: WiFi

I’ve seen a number of projects posted using the Amazon Kindle as a “standalone” wireless display and decided it was time to join the party. I picked up a secondhand kindle from eBay for £20 and got cracking.

First step was rooting/jailbreaking the kindle. Pretty easy using the instructions from http://www.mobileread.com/forums/showthread.php?t=88004

I then enabled SSH over WiFi so I didn’t have to mess around booting into diagnostics mode and plugging in to USB every time I wanted to make changes.

Lees-Air:~ leetickett$ ssh root@

Welcome to Kindle!

#  N O T I C E  *  N O T I C E  *  N O T I C E  # 
Rootfs is mounted read-only. Invoke mntroot rw to
switch back to a writable rootfs.
[root@kindle root]#

The most helpful project to get me started was https://github.com/antimega/kindleframe it uses PhantomJS and pngcrush on a linux server to prepare the image. Handily I already have a Centos server I could easily use for this. I tweaked Chris’ script a little- starting with the shell script called by cron;

cd /var/www/html
phantomjs update.js
convert morning.png -resize 80% screenshot.png
convert morning.png -rotate 90 screenshot.png
pngcrush -c 0 -nofilecheck screenshot.png screenshot_crush.png

Then update.js. I had to tackle a few issues;

  • Cycling between different pages (achieved by dividing the current minute by 5 and choosing a URL based on the remainder)
  • My SSRS report takes 15 seconds to run (using setTimeout(takeScreenShot, 20000); ensures the report has loaded before the screenshot is taken)
  • My SSRS report requires authentication (simply adding page.settings.userName = ‘x’; and page.settings.password = ‘y’;)
var page = require('webpage').create();
var d = new Date();
var n = d.getMinutes();
var url = '';
var px_top = 120;
var px_left = 10;
if (n%5==0)
 url = 'http://pvoutput.org/intraday.jsp?id=26603&sid=24317';
else if (n%5==2)
 url = 'http://pvoutput.org/list.jsp?id=26603&sid=24317';
 url = '';
 page.viewportSize = {
  width: 1920,
  height: 1080
 page.settings.userName = 'xxx';
 page.settings.password = 'yyy';
 px_top = 45;
 px_left = 470;
page.open(url, function () {
	page.clipRect = { top: px_top, left: px_left, width: 1000, height: 750 }; 
	page.evaluate(function() {
    	document.body.bgColor = 'white';
        var elapsed = 0;
	setTimeout(takeScreenShot, 20000);
	function takeScreenShot() {

Then added the script to cron to run every minute and voila.

Once SSH’ed onto the kindle you’ll need to;

mntroot rw

Then proceed to create the script to grab the image and display it (I also added a few lines to display the battery %age in the bottom corner);

cd /var/tmp/root
rm screenshot_crush.png
eips -c
eips -c
wget http://user:pass@tickett.dyndns.com:777/html/screenshot_crush.png
eips -g screenshot_crush.png
local batt=$(cat /sys/devices/system/yoshi_battery/yoshi_battery0/battery_capacity)
eips 1 39 "$batt"

I’ve setup port forwarding on my firewall to allow traffic through on an obscure port, added a .htpasswd and you’ll notice i’m using an external domain name in my script (i’ve substituted something fictitious)- this allows me to use the display anywhere with an internet connection (literally anywhere as I can tether to my mobile phone).

And here it is;




Here’s how the SSRS report looks in it’s full glory (you can see the area i’ve chosen to display on the kindle);


I’ve chosen not to kill powerd and framework for now, so the kindle will still go to sleep. The next step- if I ever get round to it, will be trying to save power by sleeping or disabling WiFi between updates. I’ve found a little bit of information on how this might be possible (http://www.mobileread.com/forums/showthread.php?t=221497) but still some way off.

I will no doubt add some additional screens (weather forecast, router traffic, network monitoring etc), and it would be nice to have a way of scrolling between images using one of the kindle keys.

Wouldn’t it be great if you could buy something like this off the shelf? Why should we have to hack an existing device? I stumbled across an interesting kickstarter campaign doing exactly this, unfortunately it’s a tiny 2″ screen (https://www.kickstarter.com/projects/914874115/displio-wifi-display-that-tracks-whats-important-t)- maybe one day!

I’m also in the market for a bigger device (i’d love to replace the 21″ monitor which sits on my wall) but for a portable option 9″ or 10″ would probably suffice. A real shame the Kindle DX was discontinued, that would have been perfect (although could do with losing the keyboard). Also looks like a few similar devices; Asus eeeReader DR900, Onyx BOOX M96 (they seem quite expensive and I haven’t looked into whether they have been (or even need to be) rooted, or how easily something similar could be achieved on Android).

Other similar projects worth a look;


An update on my latest project

Further to: https://tickett.wordpress.com/2012/12/31/a-new-year-a-new-project/ I have discovered quite a few things, and it looks like I’m not going to have to start from scratch (although I may still be designing some form of hardware, it’s hard to tell at this point).

Existing projects/products set out to do something similar:

NPlug- http://www.indiegogo.com/projects/283102/x/2060579

  • Consumption measuring (believed to be more accurate than existing devices)
  • Remote switching
  • WiFi connected (requires no bridge/gateway device)
  • Zigbee 802.15.4 for connecting to other devices
  • USB option (add 3G dongle, additional RF interface etc)
  • SoC running OpenWRT Linux
  • Open source
  • Lots more…
  • £100 (estimate)

This is really meant as a single device and not to be used with every appliance in the home. The device acts like a gateway itself and aims to connect to existing consumption/switching devices such as the IRIS / AlertMe suite.
I have pledged as a sponsor for this project, and hope to get my hands on a prototype- however, the funding has been a bit slow, so please help out :)

AlertMe (IRIS)- https://www.alertme.com/shopping

  • Consumption measuring
  • Remote switching
  • Zigbee
  • Requires the SmartEnergy pack as a bridge/gateway to the internet
  • £25

Ubiquiti mFi mPower- http://www.ubnt.com/mfi#m-Power

  • Consumption measuring
  • Remote switching
  • WiFi connected (requires no bridge/gateway device)
  • Comes in 3 flavours: Single, 3 socket extension cord and 8 socket extension cord
  • Only currently available with US / EU plugs
  • No EU stock currently available (when it is, I will try one with a UK plug adapter)

Belkin WeMo Switch- http://www.belkin.com/uk/c/WSWH

  • Switching only by the look of it
  • WiFi connected (requires no bridge/gateway device)
  • £40

Meter Polug- http://www.indiegogo.com/meterplug/x/2060579

  • Consumption measuring
  • Remote switching
  • Bluetooth only- so unless you’re within range and carrying a bluetooth equipped device, it’s not much good. This being said, the project has been fully funded, so there is clearly demand for such a device.
  • I have asked whether they’ve considered building a gateway device to enable internet connectivity but yet to hear back. Fingers crossed.


  • I have purchased a USB Zigbee packet sniffer in the hope that I can make sense of some of the traffic floating around my house from various “smart” gadgets.
  • Still waiting on delivery of my EVE Alpha board- http://www.kickstarter.com/projects/ciseco/eve-alpha-raspberry-pi-wireless-development-hardwa this should allow me to start doing some cool stuff with a raspberry pi using the gpio pins rather than dozens of USB sticks!
  • The guys over at flukso have confirmed that they will be continuing work on their enhanced hexabus plug once they have another project out of the way: https://www.flukso.net/content/hexabus-plug
  • I sent some details to a few companies in an attempt to understand costings for PCB design, production and assembly. Just one company has responded to date: http://www.newburyelectronics.co.uk/ – for something like the Hexabus plug they’re suggesting (rough figures): £1,000 PCB design (£500 each of the 2), £80 PCB production (£40 each of the 2), £60 parts (excluding several parts they can’t source), £130 assembly & inspection. Bringing the total in at about £270/device (forgetting PCB design)- ouch!

That’ll likely be my last update for a few weeks, as I’m off to Thailand shortly :)


A new year, a new project

*EDIT*: Update on this project https://tickett.wordpress.com/2013/01/10/an-update-on-my-latest-project/

So I realise I have been a little quiet on here lately, and so will make it my new year’s resolution to get back in the habit of blogging regularly.

I would like to share some details of a project I’m assessing for feasibility. It is yet to be named but in essence I’m looking at building an Automated Mains Plug / Socket, let’s call it aPlug.

What do you mean by automated?

  • Remotely switchable / “programmable”
  • Monitor / log power / energy consumption

Don’t these already exist?

  • A lot of rf controllable plugs exist but there are a number of limitations- # cannot integrate with other equipment, # cannot operate from outside of the home, # cannot operate without the supplied remote, # cannot determine current state
  • Some power / energy consumption monitoring plugs exist but again, bare limitations- # cannot integrate with other equipment, # require a gateway device to post data to the internet
  • A few devices even exist which address both requirements but- # cannot integrate with other equipment, # cannot operate from outside the home, # require a gateway device (possibly even an entire pc to post data to the internet), # are expensive, # are closed source

There is however, one possible hope! The hexabus plug: http://signup.hexabus.net/ – I am trying to make contact with the guys behind the hexabus plug to determine where the project is currently, where it’s headed etc. Regardless, the great thing about the project, it is open source- which means the schematic / parts list (BOM) have been published: https://github.com/mysmartgrid/hexabus – unfortunately the PCB layout doesn’t appear to’ve been, but again, I’m hoping it will be shortly.

This project has also sparked the interest of the guys over at flukso, and became the center of a talk at one of their meetings: https://www.flukso.net/files/presentations/flukso.20121026.hack_hexaplug.pdf – where they have suggested a minor tweak to enable interconnectivity with jee labs devices (they include a PCB layout, which suggests they likely have them- I am trying to make contact with them too!)

Even if I manage to make contact and get details of the existing device I still have a lot to tackle…

Network connectivity
I’m currently looking at options, but it makes sense to try and learn from the lessons the guys behind LIFX: http://www.kickstarter.com/projects/limemouse/lifx-the-light-bulb-reinvented
They have essentially gone down the route of creating a mesh network with “slave” devices, then using a “master” device to bridge to the local area network (LAN) and essentially the internet. This ultimate is a gateway device but “in disguise”- and unless I can miraculously find a way of driving down the cost I can’t see any other approach being feasible?

I am making contact with a number of companies who design, produce and assemble printed circuit boards (PCBs) as a number of the components involved in the device cannot be soldered by hand nor can the circuit(s) likely be built using a simple breadboard. I imagine this is going to be a real challenge as the cost for “one-off” or very limited production runs is likely to be extremely high.

Software / Firmware
I have coded some simple arduino / atmega programs in the past, and worked with some of the jeelabs devices but I will certainly be needing assistance to build something as complex as this if it’s going to be robust enough to put “out in the field”. My hope is that developers will show a keen enough interest and we can build something as a community. The devices will be reprogrammable so new firmware can be flashed with relative ease. The problems will come when a hardware change is required…

Regardless of whether a device is faced with mains voltages or whether a device is aimed at developers I anticipate some form of certification being required- this could be tricky (especially on an evolving device).

To gauge interest, boost funding, promote the project and hopefully attract some developers, testers and contributors I would like to run a kickstarter project- unfortunately it’s a little chicken & egg as I need at least some form of prototype before I can reach out to the community. I have however drafted a project so I am prepared if I do get that far: http://www.kickstarter.com/projects/tickett/736265394?token=98a4e52f (so far just some notes, and the reward levels are pure guesswork).

I just knocked the artwork up from a few google images:

I have asked someone to design some artwork for a t-shirt, so I will see if they can come up with a cool concept :)

Where Next?
Yes, it’s far too early to be thinking about that, but I can’t help it!

  • Multi socket extension lead type device with individual socket switching and consumption monitoring
  • aSocket, essentially a mains socket with the device inside so no “plug” is required
  • Other plug types (I am based in the UK so this is where I intend to initially focus)

At this stage I’d appreciate any feedback, or expressions of interest etc

Happy new year to all


Home Security Cameras

I’ve been in the market for a while but couldn’t make a decision. Finally I thought I’d give the Ubiquiti Aircam a go: http://www.ubnt.com/airvision

Here you can see it mounted just below and to the left of the satellite dish:

And a bit closer up:

Quality isn’t amazing (1 megapixel) but price (£100), interface and ease of use make up for it:

I have another camera but have yet to mount it.

Currently the Aircam is running off of the included POE injector but I have ordered a few adapters to allow me to run them straight from my POE switch: http://www.ubnt.com/8023af

I have also ordered a Ubiquiti Unifi access point to try: http://www.ubnt.com/unifi and a pair of Nanobridge M (NB-5G25) combined bridge/antenna: http://www.ubnt.com/nanobridge with which I will attempt to create a link to a house "down the road".

*EDIT* As per request i’ve added a few bits.

Performance at night is pretty poor (no ir night mode) and i’ve got quite a bit of ambient light around. I intend to add a motion activated light in the back garden eventually though.

The web interface does work from my iPhone but it doesn’t look like it’s really designed to:

I’ve not noticed any options for text/e-mail alerts but once i get my hands on a raspberry pi and start using some form of central home automation software I will most definitely be looking at integrating it!


The parents are moving today to within about 1mile of my house. I’ve been contemplating whether I could get a WiFi link setup and pop a fileserver at theirs for off-site backup… Watch this space :)

I’m off to Germany tomorrow until Thursday for a IT conference, fingers crossed for the weather and hopefully I’ll have a few updates when I’m back.


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