Project: greenhouse

The week delivered all the parts, now they go into one chip: a greenhouse with a hydroponics device, a Harvie, a heater and a grow light.

The setup#

The rules#

1. Climate: heater on below 20 °C, off above 24 °C. Without the sensor it stays off.
2. Light: the grow light follows the switch Open. If the switch is missing, it stays off.
3. Harvest: with a free arm, harvest when Mature = 1, and plant when the tray is empty and there are seeds in the import.
4. Display: MaturityRatio in whole percent, −1 for an empty tray or a missing device.
5. Warning: light on below 15 °C, without the sensor or without seeds.

Milestones#

1. The heater holds 20 to 24 °C with hysteresis.
2. The grow light follows the switch.
3. Ripe plants are harvested, empty trays are planted.
4. The display shows the ripeness in percent.
5. The warning light reports cold, missing seeds and a failed sensor.

Split the code into five sections, just like the rules. Each section reads what it needs and writes exactly one or two devices. Then you will find a fault later within a minute.