In this article, we connect a KY-003 Hall Magnetic Sensor to a Raspberry Pi Pico, any Rp2040 type board will be suitable. We actually tested this with a Cytron Maker Pi Pico
We will use Micropython for these examples but of course you can use the Arduino IDE as well if you have Raspberry Pi Pico support enabled
This module uses a 3144EUA-S Hall-effect switch IC
A Hall effect sensor is a type of sensor which detects the presence and magnitude of a magnetic field using the Hall effect. The output voltage of a Hall sensor is directly proportional to the strength of the field.
Hall sensors are used for proximity sensing, positioning, speed detection, and current sensing applications. Frequently, a Hall sensor is combined with threshold detection to act as a binary switch.
The sensor looks like this
Parts Required
You can connect to the module using dupont style jumper wire.
| Name | Link | |
| Raspberry Pi Pico | ||
| 37 in one sensor kit | ||
| Connecting cables |
Schematic/Connection
| Pico | SENSOR |
|---|---|
| GPIO28 | S |
| 3v3 | + |
| GND | – |
Code Examples
Basic example
from machine import Pin, Timer
from time import sleep
# Initialization of GPIO28 as input
sensor = Pin(28, Pin.IN, Pin.PULL_DOWN)
# Continuous loop for continuous serial output
while True:
if sensor.value() == 0:
print("No magnetic field")
else:
print("Magnetic field")
print("---------------------------------------")
sleep(0.5)
REPL Output
You will need to find a magnetic source and move it close to the sensor
>>> %Run -c $EDITOR_CONTENT
No magnetic field
—————————————
No magnetic field
—————————————
No magnetic field
—————————————
No magnetic field
—————————————
No magnetic field
—————————————
No magnetic field
—————————————
No magnetic field
—————————————
No magnetic field
—————————————
Magnetic field
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Magnetic field
Links