With the workshop closed out, the next two days were reserved for deployment and installation of the sensor nodes. The night before, I had modified the code the participants were using to harden it a bit for an actual deployment. The main thing I added in was a watchdog timer and protection against a few failure scenarios. The main ones I was concerned about were if the software hangs, if it fails to get an IP address, and if it fails to get a connection. I added in an 8 second watchdog timeout for code hangs and also would trigger a reset if the device failed to get an IP address or had a connection failure three consecutive times.

That morning, I had a short meeting with everyone to brief them on what the code changes were and how the deployment would go. I explained the changes I made to the code they worked with and why I made them. Unfortunately, we didn’t have time in the labs to cover more advanced topics like watchdog timers, timestamping, and power management. That would need to be saved for future workshops. After the discussion, we packed up our supplies and headed out to the site.

I had one free weekend after arriving at Dharamsala. I contacted Mikey from Air Jaldi, one of the workshop organizers, and he took Jacinta and I around for a site survey and also to discuss the workshop agenda.

The workshop consisted of three major parts. The first part was the actual workshop to teach the participants about sensor networks using Arduino. The second and third parts were actual sensor network deployments at the Tibetan Childrens Village (TCV) and Sarah Tibetan Center for Higher Learning. In both deployments, we’d deploy sonar water level sensors to measure the water level in storage tanks fed by nearby streams, then upload the levels to Cosm servers.

I finally arrived in Delhi, India and the first thing I noticed was that immigration was opulent. I was a bit nervous because I was there on a tourist visa but had a huge amount of wireless electronics in my suitcase. If customs checked me, it’s likely they would have confiscated most of the electronics and rendered the workshop useless. Luckily, they didn’t and I was allowed to proceed to the exit. Customs always freaks me out, mostly because I usually have a lot of strange electronics gear in my suitcase.

It was now about 1am outside of the Indira Gandhi airport in New Delhi and it seems like India hits you like a ton of bricks. The sights, sounds, and smells are all in your face. Taxi drivers were all over the place trying to hustle me into their cabs. The first taxi driver quoted me 1200 rupees (~$24) to get to my airport hotel. After talking to multiple drivers, I got the price down to 400 rupees (~$8). After arriving at my hotel, the guy at the front desk said 200 rupees was on the high side to get to the hotel since it was right next to the airport. That kind of calibrated my expectations which meant that I was in a high ripoff zone. I later found out that it’s to be expected for foreigners in Delhi.

As I'm writing this, I'm waiting at Narita Airport in Tokyo for my flight to Delhi. How I ended up here is kind of interesting.

My New Year's resolution for 2013 was to travel less so that I could get more work done. As soon as the new year started, I was on a plane to Shenzhen to help Bunnie run factory tours of Shenzhen for MIT Media Lab. That was an amazing adventure but when I got back to Tokyo, I was far behind schedule on a lot of projects I was working on. On top of that, my funds were running low since I hadn't released a new product in a while. That's another weird story since, looking back at 2012, I actually had close to 20 PCB designs fabbed. None of them were for my webshop though. Apparently all of them were either collaborations (some of those are really interesting and will be saved for another blog post) or made for my own amusement. Ha ha ha.

Hi everyone.

Robin Scheibler, a Safecast member and also a Freakduino user, discovered and informed me about a dangerous bug in the AVR settings on the Freakduino. All Freakduinos purchased before 2013-03-28 are set to have a 4 kB bootloader (2048 words). In the Freakduino tutorial,  I mention to use the Arduino IDE board setting "Arduino Pro or Pro Mini (3.3V, 8 MHz) w/ATmega328". This board setting assumes a 2 kB bootloader (1024 words). Using this board setting, the Arduino IDE will protect against any sketch that uses more than 30,720 bytes. However since the bootloader on the Freakduino is set to 4 kB, the bootloader starts at 28,672 bytes. Any sketch that's between 28,672 bytes and 30,720 bytes will overwrite the bootloader. 

There are various workarounds for this: