Brighton and I have decided the methods of information display we want to bring to Queen’s: LEDs (blue for hypothermia, green for normal temperature, and red for hyperthermia), an LCD that displays temperature and the words “HOT”, “Normal”, or “COLD”, and a three-digit 7-segment display. The LED display had already been built, because we were considering using it with the KMC Monitoring system. However, we had to build circuits and write code for both the LCD and 7-segment displays.

Brighton is studying electrical engineering, so he focused on the circuits while I sat down to learn how to code literally anything for Arduino. With the help of Tahir, Matt, and Google, I eventually figured out some basic functions. Controlling a 7-segment display takes quite a bit of information, since you need to tell which LEDs to be on when. Controlling 3, the number we need to display temperature, is more difficult. At the Poly, we only have individual 7-segment displays, so in order to use them we must wire together segments and control segments and digits using a tool called a shift register. This is quite complicated, and using a 4-digit 7-segment display would be much simpler.

For this reason, Brighton and I went to Limbe (the part of town that has many shops for electronic components, cloth, tools, and pretty much everything) in search of a 4-digit 7-segment display. We went to 6 shops that morning. At the first 4, they said they did not have them. At the 5^th, they initially asked if it was something you attached to a cellphone. When we explained what it was, they told us that they did not have it. The owner of the 6^th shop was the first to know what it was. Unfortunately, however, he did not have the display either. He said that he used to carry them, but no one ever asked for them, so he never restocked when he ran out. He then added that the same had happened for breadboards.

This surprised and saddened me. The 4-digit 7-segment display is not a very complicated component, and the idea that it was not available anywhere in the city shocked me. How can people create new technology if the instruments for doing so are not available? I was struck by how lucky we are at Rice: if we need a component, we go down to the Electronics lab or ask a professor and they probably have it. On the off chance that it is not available, we order it on Amazon and get it in 3 days, free shipping. Here, if a component is not available, you need to figure out a work-around.

In the end, Brighton and I found a relatively simple way to multiplex 3 7-segment displays to generate the display we needed. However, it was still much more complicated than it would have been had we had the desired component. Because we needed to use significantly more wires, loose connections were a bigger problem and it was generally less elegant than it could have been.