Dilshan Jayakody designed and build a programmable light controller that is able to turn ON and OFF a LED at predetermined time of each day. All the design files and source code related to this project are available at https://github.com/dilshan/programmable-light. The complete documentation of this project is also available at Github Wiki.
To meet the above requirement I designed this controller using ATmega8 MCU and DS1307 RTC. The driver stage of this light controller is intended to work with commonly available 7W LED modules. The core component of this programmable light is ATmega8 low power CMOS microcontroller. The main reason to select this microcontroller is it’s lower cost and higher availability. Except for the above two reasons this microcontroller also bundled with a rich set of peripherals which including 23 GPIOs, 3 independent timers, Two-wire serial interface, EEPROM, etc. Apart from ATmega8 microcontroller, this system uses DS1307 real time clock to maintain system time. Like ATmega8, DS1307 is also a very popular RTC in the market.
Programmable light controller with ATmega8 and DS1307 – [Link]