I got my APEM 3 axis joystick few days ago and decided to give it a little test run before my Xbee radios arrive.

Very fast testrun of APEM analogue joystick


So, I actually havent had a chance to program arduino, so that is how I decided to run the test. Arduino programming took around 10 min and soldering took around 1h. Also, the display shows only two axis, but all three work. I just did not have a third row on this HD44780 driven display.


Ladybug drone death.

On November 25, 2012, in Misc, by Cmc

A few days ago I got myself the Ladybird V2 – a quadcopter. It was awesome until it had a little accident and fell about 15 meters. Well, the drone seemed to survive the fall all right, but something was amiss… One of the motors didn’t work. After debugging it with the oscilloscope I concluded that the problem had to be with one of the motors.

Broken brush

Yes, that was exactly the problem. One of the brushes from the (brushed)motors had broken or burned off. One of the brushes has 2 needles and the other one has only one of those and even that is 90′ at the wrong angle. Well, I guess this motor will not start any time soon. Sad… Maybe I can do something fun with the cypress RF chip that this setup was using, or maybe even reprogram the atmega?  Hmm. Will take a deeper look into that.


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Gopro hero bus hacking.

On November 17, 2012, in Misc, by Cmc

Heya everybody!

Yesterday I had my luck with hacking gopro3 herobus. What was needed was access to the bus’s composite video out.

There are forum posts that suggest going for output channels and that should do it. Sadly that is enough only for some gopro firmwares. And none of gopro 3 firmwares.

I did find a forum post that suggested using i2c eeprom, but the forum post used too large eeprom. Gopro uses only 1byte adress for eeprom access.

Although the information about connections and byte location were true.

So, the gopro 3 hero bus can be made to put out analog video by using i2c eeprom that has 1 byte memory addressing and also the eeprom needs to have first byte writen to 0×09. In addition to grounding pin 22 and pin 21.  Slightly broken directions can be found here. The tutorial is broken because the gopro 3 is unable to read eeprom with 2byte addressing.

Herobus interface with i2c eeprom

Composite video output from my very cheap oscilloscope.


First Vlog test.

On September 12, 2012, in Misc, by Cmc


My first test on Vlogging.  Stay tuned!!