Hot liquid temperature sensor
In principle, this system is a coffee temperature sensor. To use the system, the end of the sensor must be inserted into the coffee cup and held there for a few seconds as it takes the sensor some time (170 ms at maximum) to detect the temperature of its environment. If the sensor detects that the temperature of the coffee falls within the pre-programmed range of temperatures considered acceptable for drinkable coffee then a buzzer will sound, alerting the user that their coffee is the proper temperature. If the coffee’s temperature is not within this pre-programmed range then the coffee’s temperature will be displayed on an LCD screen, so the user knows if they need to warm or cool their coffee to bring it into the proper temperature range. Lastly, the totality of the system will be battery powered, as maintaining the MSP432’s laptop-based power connection near liquids is not a particularly safe idea, and packaged in some sort of self-containing fashion. Additionally, it is important to note that the temperature sensor interfaces with the MSP432 using 1-wire SPI. While traditional SPI requires 3 wires (CS, Data_In, and SCLK), 1-wire SPI uses a series of switches to generate these signals from the Data input signal. This is diagrammed below in a figure borrowed from the data sheet of the waterproof temperature sensor.