This project is based on the timer/counter 0 example. It shows time, date and temparature on 7 segment displays. Instead of the LCD display the time is shown on a four digit 7 segment display with common cathode. The date and temparature is shown on a 7 segment LED display with comon anode.
The ATMEGA328 is used to control the display, the ATMEGA8 can also be used. The circuit use 6 I/O pins from port B and 2 I/O pins from port C to control the digitts and 8 I/O pins from port D to control the segments of each digit. The temperature is red from a LM335 temperature sensor.
The core of the circuit is the ATMEGA328 microcontroller. The four segment LED display is connected to PORTC and PORTD. With multiplexing the data will be show on the display. Via the I/O port of PORTB and PORTC the digits are switched on and off while PORTD select the segments.
For more detail: Clock/temperature LED display
This free embedded project also found using:
- digital 7 seg clock with alarm using avr
- digital clock by atmega32
- led clock avr projects with source code