People need water to survive, so do plants. Soil moisture indicates the moisture in the soil. As
long as the soil moisture value is suitable for the plant, the plant can get water from the soil.
Therefore, in this experiment, we will make a plant soil moisture detector to ensure that our
plants can get enough water and grow.
Experiment 7 – Plant soil moisture detection
Instruction
Learn how moisture sensor work and use it to make a moisture detector with LED and buzzer.
Learn how to draw icon on Micro: bit's matrix LEDs.
Learn how to use if/else if/else statement.
Micro:bit x1
Crowtail-Base shield for Micro:bit x1
Crowtail-Moisture Sensor x1
Crowtail-LED(Yellow) x1
Crowtail-Buzzer x1
Crowtail-Cable x3
USB cable x1
Target
Required Parts
This Moisture sensor can be used to detect
the moisture of soil and thus to monitor if the
plants in your garden need some water.
This sensor uses the two probes to pass
eletricity through the soil, and then reads the resistance to get the moisture level. More water
makes the soil conduct electricity more easily(less resistance), while dry soil conducts electricity
poorly(more resistance). Compares to the other moistures sensor using the same moisture test
method, this module has super long legs, making it suitable for actual applications.
Connect Crowtail-Moisture Sensor, Crowtail-Buzzer and Crowtail-LED to P0, P1 and P2 ports of
Crowtail-Base shield for Micro:bit. The hardware connections are as follows:
Hardware learning and connection
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