Question

HARDWORK

In this lab, you will make a digital thermometer using the SEN-11931 breakout board as well as the 4-bank seven-segment LED display. Design the hardware connection of the SEN-11931, reuse the 4-bank 7-segment LED connection from Lab 4 for the mbed to read the temperature from the SEN-11931 and display the temperature in Fahrenheit degrees on the LED display in the format of xxx.x. Build your circuit and include all the required information about your hardware design in your lab report. You will also need to make the decision on whether pull-up resistors are needed. Based on the hardware you designed, write a code that takes temperature measurement every 5 seconds and display the temperature in Fahrenheit degrees in the format of xxx.x (for example: 098.6 or 104.8) on the 4-bank seven-segment LED display.

Answer 1

Digital Thermometer Using SEN-11931 Breakout Board:

Here you will be needed to use SEN-11931 breakout board (sensors) to measure the temperature and to display the temperature in fahrenheit degrees.

Do we need pull up resistors?

The Breakout Board SEN-11931 ie ( TMP102) has an inbuilt 4.7Kohm inbuilt pullup resistors for I2C communications and thus we dont need any external pull up resistors.Provided this works from 1.4V to 3.65V.

Also this I2C communicatrions are using an open drain Signalling, so we dont need level shifting also.

Circuit Diagram:

here we are provided with a 4 banks of 7 segment displays. Now the circuit diagram of the hardware connections of the temperature sensor (TMP120) with the PIC16F1829 microcontroller and four 7 segments display is shown as,

Program :

The program which is used to take the temperature reading for every 5 seconds and displays the temperature measurement in Fahrenheit degrees on the 4 seven segments displays is given as,