Pomodoro Timer

Create a basic Pomodoro timer
, a cube-shaped board that can sense direction and accurately count down. Choose a 1.6mm thick PCB. Separate two boards and solder them vertically,
connecting the ground wire in the middle using a bent pin header.
Use an SW-00D sensor;
pay attention to the pin orientation during soldering: the two ends are silver, and the middle is gold. The sensor is easily damaged by high temperatures, so avoid prolonged heating.
Use a common-cathode digital display. Because it's I/O powered, no transistor is used, resulting in lower brightness. A port is provided, requiring jumper wires... (Note) .
Two slide switches control the buzzer and battery power respectively (to alert you when the countdown ends, to avoid disturbing others). I didn't connect a lithium battery; I've always used Type-C power.
Note: The crystal oscillator is 12MHz. Due to some issues with the buzzer circuit, jumper wires were used...!!
The casing uses FDM with a precision of 0.2. STL is not included; the attached instructions are for modification . Countdown
 
 
:  
Display the corresponding time >> Button 3 (Start Countdown) >> Countdown ends (buzzer sounds) >> Button 2 (Stop sounding)
Stopwatch: Button 1 >> Stopwatch starts >> Button 1 >> Stop timing >> Button 2 (Reset)