My slides about DevOps for workstations (talks about Chef, Vagrant & VeeWee mostly) from yesterday afternoon presentation at Devoxx FR are now available (in French only):

I finally received my order at SeeedStudio last Wednesday. It came nicely packaged and until yesterday, I had not a chance to test the Stalker. After a few hours playing with it, I must say that this is a really cool Arduino board from which you can do plenty of stuff.

I went through the tutorial for the Stalker v2.1 on the Wiki and experienced a few glitches for which I found solutions that might help some of you :-)

The problems I had where mostly related to:

• compatibility with Arduino 1.0
• interrupts

I’ve just placed an order yesterday at SeeedStudio. Plenty of interesting stuff to play with for quite a bit :-)

Seeeduino Stalker - Waterproof Solar Kit (x2)

I’m getting more and more interested in XBee/ZigBee networks so the Stalker with be something interesting to play with. I already have a bunch of XBee Series 1 modules, I plan to order some ZigBee ones later on, probably via Mouser.

I plan to use ZigBee modules instead of XBee ones mostly because of the Mesh topology I’m interested in. I’m still undecided regarding which ZigBee modules I’ll buy: probably non-Pro for outdoor projects and Pro version with RPSMA antennas for indoor (I hope to get one day some interesting Home Automation ZigBee modules and the Pro version is the only one that will ease the integration with those 3rd party modules).

Energy related stuff

• 3W Solar Panel: the 0.5W panels included in the Waterproof Solar Kit are interesting because they fit in the enclosure, but I’m wondering what a larger panel might mean for a few outdoor projects I plan to work on
• LiPo Rider Pro with 2 x LiPo 6A: I assume the built-in LiPo charger in the Stalker won’t be beefy enough

Various things

• 5mW Laser Module emitter - Red Point: I never had a chance to use some lasers as powerful as this one. I’ll see what I can do with it :-)
• and various Bus Pirate related stuff that will proove useful when testing some ICs or components.

Now I have to wait a few weeks ‘til I receive this stuff. Will let you know how this turns out.

Meanwhile I’ve been working on the project I briefly talked about in the previous post (more on that in a post later on), and finally got a chance to work on the Pololu Robot I had bought a few weeks ago.

I bought yesterday a LilyPad TechStyles Kit from Lextronic.

This is a really simple kit with which you can easily start sewing some electronics.

I bought it because it comes with some handy parts, like the switch, the coin cell battery handler and some few LEDs.

Here is what you end up with after it’s completed (you can’t see well the blue LEDs turned on):

Turns out I spent quite a bit of time sewing :-)

I guess my skill will improve with time & training.

I will soon talk about about a homemade gift I started to work on today for an anniversay. This gift will be based on some scrapbooking stuff (not done by me! :-)) and will use some LilyPad stuff in order to enhance it.

More on that in a few days.

This blog post is focused on how to design a REST API implementation with:

• good productivity,
• great performance,
• a decent auto-generated/always up-to-date documentation for REST API users/developers, including REST API libraries for many of the popular languages.

I’ll explain here what I used to do ‘til last week and some few projects I’ve discovered recently which have helped me a lot in order to achieve the above goals.

While doing some development in Java (using RXTX like the Arduino IDE does), I always had errors like this one:

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Caused by: gnu.io.PortInUseException: Unknown Application
  at gnu.io.CommPortIdentifier.open(CommPortIdentifier.java:354)
  at com.rapplogic.xbee.RxTxSerialComm.openSerialPort(RxTxSerialComm.java:97)
  at com.rapplogic.xbee.RxTxSerialComm.openSerialPort(RxTxSerialComm.java:61)
  at com.rapplogic.xbee.api.XBee.open(XBee.java:140)
  ... 2 more

I was puzzled because I could not find any other program using the serial port!

Turns out Google is your friend on this and the error message is very misleading.

The RXTX library requires access to the /var/lock directory, but it does not exists on a Mac!!!

So you only need to create it properly: Liquid error: ClassNotFound: no lexer for alias ‘shell’ found

via JGrass Tech Tips

I’ve been digging online for the last few weeks/months in order to find some retailers from which I could buy some Arduino related stuff and electronic components in general. Before I introduced it, I have to say that I usually prefer to go to a retail store rather than buying online in order to support the local stores. I appreciate to be able to get what I need within a few hours. So as long as local stores prices are close enough to the online stores, I’m fine with it.

Hoping this will help some of you, here is below a non-exhaustive list of what I found (this is by no means an exhaustive list – I chose to put an emphasis on some interesting online shops). If you feel like I missed some really important shops, let me know!

Following my recent hardware purchases, I wanted to be able to have an Android phone to talk to an Arduino.

Being an iPhone kind of guy, I did not had a recent Android phone. Hopefully my parents got rid of a ZTE Link device a few months ago. This devices runs on Android 1.6 (Donut), so a really old version of Android, and can’t be updated to any recent version.

I was expecting some issues because of the old version of Android, but this turned out NOT to be a problem.

As much as I like Internet when I need to find some information or buy some stuff, I always prefer to buy from a local shop when the price is right (meaning rather close to what I can get online).

So I went last Saturday to my local electronics store (local being 50 kilometers though…) and bought more stuff that I think will prove to be useful. Quick list of the most interesting stuff:

• Bus Pirate and its cable: should help figuring out how to use some ICs and quickly prototype/hack some devices (I have a bunch of iButtons left from a few years ago),
• 2 more XBees (Series 1, can’t easily find Series 2 actually…): so now I have 4 which will make things more interesting,
• a Pololu 3pi robot (chassis, 2 motors, 2 wheels and a ball caster) with a shield for driving those 2 motors: will be my first experiment which robots,
• a BlueSMIRF module (Bluetooth module): I initially plan to use it with Amarino in order to control my hacks via an Android phone, but this will eventually be used also for wireless upload of Arduino sketches.

I actually intended to buy way more stuff but this is the only things they had in stock or they are selling. I need to order many things online now (I’ll post again with the new shopping list(s)).

Turns out yesterday I was able to quickly mount the Pololu robot. Unfortunately I miss some stuff in order to mount an Arduino on the chassis :-(

I also got a basic connection with the BlueSMIRF module: my MacBook Pro talking to the module. I need to go through its documentation though. I was able to talk to the module (in command mode) via a terminal, so I suppose this shouldn’t be that difficult to use :-)

Oh! I also found a way to get 2 desks: one for computers and another one for electronics. Now I have some space available on both desks which is really really appreciated!

I heard a lot about using XBees for radio transmission between Arduinos and/or PCs. I decided to jump on this a few days ago and began by reading the excellent Building Wireless Sensor Networks book.

After intensive lecture sessions, I felt confident enough in using XBees and did a quick run yesterday afternoon into my “near-by” electronics shop and bought 2 XBees Series 1, two shields for the Arduino and finally a Sparkfun XBee Explorer USB.