Digital Display with Clock and Temperature

The project illustrates a digital clock and temperature display which makes use of alternating display between time and temperature.

The display time of the device has 24-hour format and the DS1307 RTC is powered by a 3V battery. The DS1820 temperature sensor contains a single channel and can measure a temperature range from -55°C to +125°C with 0.5°C accuracy.

Along with the temperature sensor, RTC, and PIC microcontroller in the circuit are the shift register, 7-segment display, and keyboard. For expanding the I/O of CPU, the shift register is used since it has 13 I/O only for PIC16F826. This shift register device contains an 8-bit serial-in, parallel-out shift register where an 8-bit D-type storage register is fed. All tasks such as reading RTC from DS1307, reading temperature, and converting data to 7-segment code are controlled by using the PIC16F826.

The CCS C compiler is used as the software for programming this project. Two things are displayed on the 7-segment which provides alternate display for time and temperature. The temperature will be displayed first after power up and blinks while displaying 8 times and then back to display time at about 10 seconds.

Rest of the project