Archive for the ‘AVR’ category

Exploring WiFly RN-131 GSX Embedded WiFi Module

October 3rd, 2009

I made the next step in the direction of WiFi. Some days ago I surfed the Internet for an embedded WiFi module for less money. And finally I found the WiFly GSX modules from Roving Networks. Their slogan is “Wireless for less” 😉

So I ordered some evaluation boards (about 100€/pcs) for me and two collegues who are studying with me at the NTB. Our goal is to have fun with wireless applications.

The RN-131 GSX Module is a 802.11 b/g wireless LAN Module with a lot of features – Details see datasheet.

If you already have a GSX Module you can use my LabView source below to show the UDP packets which the module sends in default configuration every 7 seconds.

The packets include

  • MAC address of AP
  • WiFi-Channel
  • RSSI (quality)
  • local TCP port
  • RTC (real time clock value)
  • NTC temperature option (if temperature sensor connected to module – otherwise sensor 7)
  • Spare sensor reading
  • ASCII time
  • Version string with date code and Device ID string

This information can be used to open a TCP connection to the module or to configure it over WiFi. The module has to be in the same subnet as your PC or MAC if you want to receive the packages.

Here are some pictures of the Module in action:

Here is the LabView (8.6) Source as LLB: wifly-monitoring-distribution

Get in touch with JAVA, TCP/IP, Mac OS X, iPhone and Objective C programming

September 23rd, 2009

Hi Guys!

In the last weeks I thought about new projects (beside the Mikrokopter project). So I started to study Objective-C programming by myself to be able to code iPhone applications in future. A good start for doing that is the book “Cocoa Programming For Mac OS X” by Aaron Hillegass.
A good podcast to start with Objective-C from the real basics is also this one from Peter and Ingo:
Another good resource that I am using is the Stanford iPhone programming course, which is available over iTunes U and resources to the course are here:

Because the SPP Bluetooth profile is currently not supported by the iPhone (OS 3.1), data transfer has to be done over TCP/IP or some other “frickel-ware” tricks (Audio, Display and Camera, other BT-profiles, …).

» Read more: Get in touch with JAVA, TCP/IP, Mac OS X, iPhone and Objective C programming

EPI-OSD (with C-OSD Software) + Camera

May 29th, 2009

Hi Guys!

Yeah, it’s summer and now I have time to continue my investigations in FPV-flying. Some weeks ago I had a little disaster and crashed my FlightCtrl and my NaviCtrl (shortcut in the connection cable).
So I had to order a new NaviCtrl immediatly. I had luck, the MK-GPS and EPI-OSD survived.

And now – my Kopter is back 😉 (better than ever *ggg*)

Ok, let’s get to the topic.

A lot of people asked me, how I mount the camera and the EPI-OSD on my Mikrokopter. Thats a little bit complicated to explain and so I took some pictures to show you how I did it.
Update – 30.05.09: Attention, if you want your C-OSD Version to work fully together with the NaviCtrl you have to connect the EPI-OSD to the debug port of you NaviCtrl!


I hope that I will have some time in the next weeks to do my first FPV Tests with video recording to post it here (maybe the weather is nice 😉

YouTube - Link: EPI-OSD Programming and Mikrokopter overview


Preview of functions of the “system-technic-robot”

May 9th, 2009

As you probably know I am a member of a team that has to built a robot. This is part of my education at the NTB in Buchs in the first two semester.

Here is a short clip of the actual status. Details will follow at the end of the project.

Some facts:

  • Robot controlled by WiiMote
  • A PC/Laptop has a relay application that realizes the Bluetooth communication (Software: LabView)
  • WiiMote -> Bluetooth -> Labtop -> Bluetooth -> uC -> Motors/Sensors (Bidirectional of course)
  • IR-Sensors (Sharp Type GPD120)
  • Stepper Motors
  • LiPo power supply (11.1V / 3p1s)

YouTube - Link: NTB-Buchs 2009 – Team6

Open tasks (“todo”)

  • give it intelligence (autonom)
  • communication with partner team
  • final documentation
  • preperation for public presentation

Speedy 😉

Mikrokopter with DUBwise V0.52

April 8th, 2009

Hi out there.

In the last days i tested the new version of DUBwise (Digital UFO Broadcasting with intelligent service equipment – coded by LiGi). The Kopter is connected via Bluetooth to the mobile device. In my case this was a Sony Ericsson W810i.

The actual Version has the possibility to adjust all Settings (like the MK-Tool) and nice features are the Graph indicator and the Cockpit which displays a virtual horizont.

It’s a amazing tool and supports a lot of mobile devices. Ligi is also updating and patching all night long to be in sync with the latest released Software from the Mikrokopter project itself (FlightCtrl, NaviCtrl)

The tool is also able to talk and tell you how full the Lipo is (Voltage). Other nice informations are the number of satellites, height over ground, heading, distance to home position and so on…

To see how the tool looks in action here is a short clip:

vimeo - Link: Mikrokopter with DUBwise

Details about the project you can find at or

Update 14.04.2009: Because some guys asked me how to install the application on their mobile phone, here is an instruction. For the installation you can use the “Installer” from LiGi (
If you have no internet connection, the installer shows you which file you have to install for your specific device. The sources and binaries you can find here:

Testing Sharp Distance Sensors

February 10th, 2009

Hi Guys!

Finally I finished the first semester of the NTB in Buchs.
Beside working for my company I had to learn a lot – but – I also had some time to combine the requirements for the “robot” project in the first year with a possible nice feature for the Mikrokopter.

I’m talking about the “traditional” IR (infrared) distance sensors from Sharp. There are different types of them, for example: GP2D12, GP2D120, GP2Y0A02YK (GP2Y0A02)
These three types are sensors that have an analog output (there are also other sensor-types from sharp with adjustable or fixed digital outputs)

The sensors have a very simple interface:

  • Power Supply
  • GND
  • Analog Out

That’s it!

The difference of these three types that I tested is the measuring distance or let me say their “sensitivity”.

For example the GP2D12 specification is:

Range: 8cm to 80 cm
Supply: 5,0V;
Vout: 0,4V bis 2,6V typ. (80cm – 10cm);
Current: 33mA typ.

Typical feedback:

As you can see the output voltage is not linear to the distance – but that is not a big problem for the softare, if you know that behaviour 😉

The GP2D120 if from 4cm to 30cm and the GP2Y0A02YK is from 20cm to 150cm.

» Read more: Testing Sharp Distance Sensors