This project introduces you to analog input by introducing a temperature sensor. In the previous project the pins we used were digital meaning they either had a high voltage or a low voltage. However an analog pin can input/receive a range of decimal values between zero and one. Once you understand the difference between analog and digital pins, this project was quite simple to complete.

First I placed the temperature sensor into the breadboard and hooked it up to an analog pin. Then I changed my program so that the 8 LEDs from the last project would now display the temperature in celsius. This required a bit of conversion to get the temperature in celsius as reading the pin first. First we convert the value returned into voltage by dividing by 1024 and multiplying by 5. Then to convert to celsius you subtract 0.5 and multiply by 100. With the reading now in celsius I went ahead and displayed it on the LEDs.

One interesting note I had while completing this project was that in order to read the analog pin, the arduino library required an analog to digital converter(ADC). Doing a little bit of research revealed that this is a circuit that is responsible for turning the analog input into a digital value we can work with. Apparently it’s common for ADCs to be implemented by using lots of comparators which are electrical components that are able to compare to voltages and give an output indicating which is higher.

Anyways this was a relatively simple project(but fun!), on to the next!