AT89S51 electronic clock design (schematic + PCB + LCD)

AT89S51 electronic clock design (schematic + PCB + LCD):

1. Use the button of P1.7 to change the level status of P2.7 to control the backlight of the 9014-driven LCD (press the button once to turn on the backlight, and press it again to turn it off)

2. Use 24C04 to store the set alarm clock and set alarm temperature, so that various settings will be available after power failure (data settings are updated every 10 seconds or 1 minute)

3. Increase the time to cycle function (if you set an alarm clock at 1:30, there will be a reminder at 1:30 every day). The P3.1 reminder is that the buzzer interval is 2 seconds, and the sound time is 1 minute. You can ring at any time. The alarm clock can be turned off with one button, and 15 alarm clocks can be set

4. Add 5 time timing functions. The LCD displays the time timer during setting. The output is P2.6. If the timer is set to 1:30, when the time is up, P2.6 will output high level for 30 minutes, and the period will start after 30 minutes. becomes low level