Coffee Grinder Timer

Timer for grinder such as mazzer mini.

Functions:
- setting dosing time
- automatic dose with pre-defined duration (timer)
- manual dose
- screen displaying the dose duration

It is essentially a timer coupled to a relay module on a 220v extension cord, it is managed by an 9v battery powered arduino, 3 buttons and a display. It does not need any modification of the grinder as the grinder just needs to be connected on the modified extension cord.
Arduino code and Fusion file attached.

Materials:
1 0.91 Inch 128x32 IIC I2C White / Blue OLED LCD Display
1 Multi Output Voltage Conversion DC 12V to 3.3V 5V 12V Step Down Buck Power Supply Module For Arduino
1 Experimental 9V Battery Snap Power Cable to DC 9V Clip Male Line Adapter for Arduino Uno R3
1 PCS Prototype PCB Board Protoboard 6x8cm Single Sided Circuit Boards Diy Universal breadboard for Arduino
15 Breadboard PCB Solder Cable 24AWG / 26AWG Jumper Wire
1 Type-C Nano 3.0 With the bootloader compatible Nano controller for ar