Have you ever worried you did not turn off your oven before you left the house? Using this project you can always know if your oven is left on using two particle photons. One photon has a thermistor in the circuit, and measures room temp of the kitchen. It then publishes the room temperature value, measured as the voltage drop across the thermistor, to the particle cloud. The second particle also has a thermistor that is placed inside of the oven. The second particle will subscribe to the room temperature event, and compare the voltage drop of the thermistor in the oven to the room temperature voltage. If the voltage of the oven is smaller than room temperature voltage, it will then publish the message "hot" back to the cloud. The first photon will subscribe to the oven temperature, and it will send off an alarm by flashing the led light on the photon three times. Both photons are powered with 3 volts from the photon, and the thermistors are in series with 100K Ohm resistors.
Equation to convert ADC Count to Voltage:
Voltage = (ADC Count)*3.3/4095
3.3 was used because that is the input voltage supplied by the Photon, and 4095 is the max ADC Count.
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