Everyone in their life remembers the school bell, which always used to bring joy to my face. This project that is an automatic school bell , that triggers at a predefined-time and also features a 16×2 LCD along with a 4×4 matrix keyboard and also a variable ringing time feature. Moreover it’s a self-operated device, no PC is require to enter the predefined-time or any other info, and also it doesn’t even feature a battery to maintain a clock and ringing schedule. I guess they might have used the EEPROM of the controller
Since it’s a standalone device, it can be directly plugged onto an Ac supply and a large number of electronic bells can be connected in parallel, to generate a particular sound. A lot of optimization has also been implemented so as to keep the bell off on certain weekends and in a certain time of the year. For the hardware, the author has used a PIC18f4520 microcontroller as the brain of the system. RTC1307 IC is used to maintain the clock, date and day with a 3V backup voltage battery. Even PCB schematics as well simulation files has been include with the project.
