Design a thermocouple-based thermometer with a range of 0 to 50°C. You can use an ice bucket for the reference, or you could design the thermistor-based thermometer of Lab 12.1 and use it to compensate for the cold junction of the thermocouple. Design your system with the best possible resolution. The temperature measurements will be displayed as fixed-point numbers on an LCD. The temperature component is 0 to 1 Hz. Experimentally verify noise level, time-constant, and accuracy of your system.

Lab 12.1

This experiment will use a thermistor and the ADC converter on the 9S12 to construct a digital thermometer. The temperature range should be 20 to 40°C. If the current temperature is above the upper limit in the specified range, a red LED should be turned on. You can test this feature by shorting the thermistor leads together (zero resistance). If it is below the lower limit of the specified range, a yellow LED should be turned on. Similarly, you can test this feature by disconnecting one wire of the thermistor (infinite resistance). Otherwise, a green LED will stay on, indicating that the temperature is within the specified range. The temperature measurements will be displayed as fixed-point numbers on an LCD. Design your system with the best possible resolution. The temperature component is 0 to 1 Hz. Experimentally verify the noise level, time-constant, and accuracy of your system.