Well after rebuilding my controller build for the Mikrokopter with the new PCB I designed I found out yesterday there was a problem.
The weird thing is that it worked for several days, no problems and then yesterday it stopped. My main control loop was hanging on an I2C read/write. I've seen this problem before, due to the voltage level converter I'm using. However, after checking the circuit many times, swapping out the converter chip things still weren't any better. The really frustrating part is that sometimes it would work for a minute or two and then hang. I checked all the voltages and connections and finally found something odd. I was getting a non "OL" (i.e. infinite resistance) between GND and SCL1 (low voltage). The resistance was very high (mega ohms) but it should have been zero. I figured it was something to do with the board and/or how I soldered the chip down (pretty small chip). I removed the chip again, cleaned things up and very carefully resoldered the chip, trying to use as little solder as possible. Once I got the chip back on I check the resistances and this time they were OL where they should have been. I connected up the board, applied power and all looks good. Hopefully this is something I can avoid from now on.
Last modified Wed, 22 May, 2013 at 13:16
