This is a LCD Display with Date and Time, 12hr format.The reason why a LCD display is used because it allows to display many characters and it does not need to be refreshed as 7-segment Led displays. Also, the interface requieres less I-O pins
For this project a 16×1 LCD Display with 4-bits interface is used
I/O pins A2, A3, A4 and A5 of the 16F628 are not used.These pins are reversed to connect a LM75 (LM75 uses I2C communication) and display the temperature. Time and date are displayed as HH:MM:SSx mmm dd, where: HH = Hours MM = Minutes SS = Seconds x = AM/PM mmm = Month (Jan, Feb, Mar) dd = Day.
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