Washing machine

A small washing machine: the drum is a DC motor on an L298N (IN1 GPIO5, IN2 GPIO6, ENA GPIO12), a 16×2 LCD (I²C 0x27) shows the phase, a start button is on GPIO26 and a slide switch is the door sensor: COM to GPIO27, pin 1 to ground, pin 2 to 3.3 V (lever right = door open = GPIO27 high).

Feed the driver's +12V and +5V terminals from the Pi's 5 V and join the grounds. On 5 V the bridge leaves the motor about 3 V: roughly 100 rpm at full speed, proportional to the PWM duty.

Line 1 of the LCD shows READY until start is pressed with the door closed (start is ignored while the door is open). Then the cycle runs:

Phase	Length	Drum	LCD
Wash	4 s	50 % speed, alternating direction every second (forwards first)	WASH
Rinse	2 s	forwards, 50 %	RINSE
Spin	3 s	forwards, full speed	SPIN

Afterwards the drum stops and the LCD shows DONE.

If the door opens during the cycle, stop the drum at once and show DOOR OPEN. The phase clock pauses; when the door closes, the cycle carries on where it stopped.

The test presses start at 1 s, opens the door at 2.5 s and closes it at 4 s, so the cycle finishes at about 11.5 s.