Grove - Hall Sensor


5.0V Digital

The Hall sensor is based on Hall Effect, which is the production of a voltage difference across an electrical conductor, transverse to an electric current in the conductor and a magnetic field perpendicular to the current. There is a continuous-time switch on this Grove. The output of these devices switches low (turns on) when a magnetic field (south polarity) perpendicular to the Hall sensor exceeds the operate point threshold BOP, and it switches high (turn off) when the magnetic field disappears. The twig can be used to measure RPM.

Version Tracker

Revision Descriptions Release
v0.9b Initial public release 3,Oct,2011


  • Grove Compatible Interface
  • 400ns transition period for rise and fall.
  • Continuous-time hall effect sensor
  • Reverse battery protection


Item Min Typical Max Unit
Supply Voltage 3.8 5.0 24 V
Supply Current 4.1 - 24 mA
Operating Temperature -40 - 85 ºC

Platforms Supported

Application Ideas

  • RPM meter.
  • Simple dc motor.

Getting Started

The Hall Sensor is used by utilizing the external interrupts available on the arduino/seeeduino. In this example we are using interrupt 0, found on digital pin 2. For other interrupts, see the attachInterrupt().

  • Connect the Hall Sensor to Digital port 2 of the Grove - Base Shield using a 4 pin cable and connect Grove-LED to Digital Port 4.
  • Then connect Arduino to PC by using a USB cable.
  • Download the Hall Sensor Code
  • Open one of two code. For example Demo MagnetControlLED

  • Upload the code.
  • When a magnet whose south pole is facing up is approaching to the onboard sensor, the LED will be turned on. Otherwise, the LED will be turned off.


ArduinoWioBeagleBoneRaspberry PiLinkIt ONE


The platforms mentioned above as supported is/are an indication of the module's hardware or theoritical compatibility. We only provide software library or code examples for Arduino platform in most cases. It is not possible to provide software library / demo code for all possible MCU platforms. Hence, users have to write their own software library.

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Happy hacking