Set up the Infineon 3D magnetic sensors software inside IDE

Published August 24, 2018 © GPL3+

Magnetic Multi Switch for Desk Lights

Camouflage visible switches with simple elegant decor to control multiple lights and devices using pointing orientation.

BeginnerShowcase (no instructions)3 hours777

Smart Home

Sensing the World in All Three Dimensions

Things used in this project

Hardware components

General Purpose Transistor NPN

RGB variable color led strip

Relay (generic)

LED light strip

Infineon 3D Magnetic Sensor 2Go

Neodymium Magnets,

Story

Video showing example of controlling LED lights

Do you have lights and gadgets that plug into a power strip and need to be easily switched on individually? Or frustrated to find the right remote button in the dark to turn on lights. Ever wish to turn simple decorations on your desk into switches?

Here is another way to control your lights and peripherals - with magnets.

I'll demonstrate how I used Infineon 3D magnetic sensors to detect the direction and orientation of magnet to map to light control.

STORY

I have a desk with many decorated LED lights powered from 12V Solar charged battery. I used couple leftover reed switch with a matching magnet from Home security system for a easy quick hookup I find it easier to switch on by sliding the magnets to activate the lights instead of pushing individual switches. I can affix the reed switch under the desk to hide the wires.

When I saw the potential application of using 3D magnetic sensors to detect orientation for more refined control. This can replace couple of reed switches with a single sensor chip.

Advantage

Customize look and feel of your own switch. Hide inside your decor or 3D printed objects.

Directional control to quick change to specific combo of switches or color by tactile orientation.

MULTI SWITCH

Instead of individual on/off switch. I used hot zones to program in set of switch controls. For example, turn on speaker that plays music by moving into a specified position on the desk. Or to selectively turn on a fan, radio, and various decor lights without reaching for hardware switches on each device.

There are overlap zones where adjacent switches will be on.

Switch zone based on magnet's orientation

Hardware

The sensor is Infineon XMC1100 XMC2Go which can detect magnets orientation in 3D space.

With magnets' north and south pole in horizontal plane orientation, sensor can detect rotational value calculated based on azimuth and polar coordinates. As well as normal value of magnet from the sensor.

Pin Diagram

When the magnetic field is within detected threshold normal value, it'll activate the switches. The rotational value will be used to change switch settings.

The control scheme is similar to a rotary switch with push button. Except the z axis has analog value based on magnetic distance and improved accuracy of the heading angle.

The XMC1100 has 1 PWM to control the white LED light strip.

I mapped the remaining switch position to control colored led lights with preset combinations.

Using the GPIO 4, 5 to control color combination of colored LED strip.

These GPIO can also be assigned to control AC devices using a Relay.

Building the LED Light Switch

The power to the LED Strips are 12V DC. A controller is needed to step up the voltage. I used a transistor to drive the power to the relay.

To control individual LED light, added TIP120 transistor and 1k resistor for each 3.3V GPIO control pin to switch 12V DC

controlling 12V DC LED lights with transistor

Testing with RGB color strip

Set up the Infineon 3D magnetic sensors software inside IDE

The firmware is programmed in Arduino using Infineon XMC-for-Arduino

Follow the instruction in https://github.com/Infineon/XMC-for-Arduino to set up.

Download the firmware for "XMC1100 XMC 2Go"

Configure the IDE

Using Arduino IDE, you need to download and add in following link:

File > Preferences > Additional Boards Manager URLs

https://github.com/Infineon/Assets/releases/download/current/package_infineon_index.json

Install XMC Microcontroller by entering "XMC" in the search box under

Tools > Board > Boards Manager.

Now add the library to compile the code by following the instruction in

https://github.com/Infineon/TLE493D-3DMagnetic-Sensor

You can now upload the firmware

Program the switch

Paste in the code "Magnetic Light Switcher" in the code section into the Arduino IDE

Adjust the sensitivity of Trigger distance

This depends on the strength of the magnet you have. LED will light up to activate the lights.

Un-comment the debug info which will print out the coordinates of detected magnetic Normal value. ( remove '//')

 //DebugInfo();

Open the serial monitor in Arduino IDE

Test to obtain the values and distance you want to activate the lights. Change the Proximity threshold value.

 float  PROXIMITY = 1.5;

Configure switch trigger zone

You can set the parameters for GPIO switch pin number, start and end range of the switches activation angle in degrees.

 SwitchOnAngleRange(SW2_PIN, 180, 270);
 SwitchOnAngleRange(SW3_PIN, 260, 350);

Activate both switches by overlapping the end angle of 1st switch with start angle of adjacent switch.

Conclusion

Using Infineon 3D Magnetic sensor as a switch is a novel and fun way to turn on gadgets with preset settings based on orientation. Though similar set up could be done with traditional reed switch and a potentiometer knob, the small magnetic sensor provides add function and flexibility for easy customization.

Code

Magnetic Light Switcher

#include <Tle493d_w2b6.h>

#define FADE_LIGHT_PIN 8
#define SW1_PIN 4
#define SW2_PIN 5
#define SW3_PIN 2
#define SW4_PIN 3
#define LED_INDICATOR_PIN 14


float  PROXIMITY = 1.5;

Tle493d_w2b6 Tle493dMagnetic3DSensor = Tle493d_w2b6();

float azimuth;

void setup() {
  Serial.begin(9600);
  while (!Serial);
  Tle493dMagnetic3DSensor.begin();
  Tle493dMagnetic3DSensor.begin();
  //Tle493dMagnetic3DSensor.enableTemp();
  pinMode(LED_INDICATOR_PIN, OUTPUT);
  pinMode (FADE_LIGHT_PIN,OUTPUT);  
  pinMode (SW1_PIN,OUTPUT);  
  pinMode (SW2_PIN,OUTPUT);  
}


void DebugInfo() {
  Serial.print(Tle493dMagnetic3DSensor.getX());
  Serial.print("\t");
  Serial.print(Tle493dMagnetic3DSensor.getY());
  Serial.print("\t");
  Serial.print(Tle493dMagnetic3DSensor.getZ());
  Serial.print("\t");

  Serial.print(Tle493dMagnetic3DSensor.getNorm());
  Serial.print("\t");
  Serial.print(Tle493dMagnetic3DSensor.getAzimuth());
  Serial.print("\t");
  Serial.print(Tle493dMagnetic3DSensor.getPolar());

  Serial.print("\t");
  Serial.println(Tle493dMagnetic3DSensor.getTemp());
}

void SwitchOnAngleRange( int switchPinNum, float startAngle, float endAngle) {
    if (azimuth  >= startAngle && azimuth < endAngle) {
      digitalWrite(switchPinNum, HIGH);
    } else {
      digitalWrite(switchPinNum, LOW);
    }
}


void loop() {

  Tle493dMagnetic3DSensor.updateData();
  digitalWrite(LED_INDICATOR_PIN, LOW);
  digitalWrite(SW1_PIN, LOW);
  digitalWrite(SW2_PIN, LOW);
  digitalWrite(SW3_PIN, LOW);
  analogWrite(FADE_LIGHT_PIN, 0);

  //DebugInfo();
  //delay(5);
  
  while (Tle493dMagnetic3DSensor.getNorm() > PROXIMITY)  {  
    Tle493dMagnetic3DSensor.updateData();
 
      
    digitalWrite(LED_INDICATOR_PIN, HIGH);
    azimuth = (3.1415 - Tle493dMagnetic3DSensor.getAzimuth()) / 6.283 * 360; // magnet heading in degrees
  
    // Fade light angle range
    if (azimuth  >= 10 && azimuth < 180) {
      float fadeValue = azimuth / 180 * 1024;
      fadeValue = constrain(fadeValue, 0, 1023);
      analogWrite(FADE_LIGHT_PIN, fadeValue);
      continue;
    }
  
    // Switch on port 1 PWM LED Light
    if (azimuth  >= 340 || azimuth < 10) {
        // Turn all on
        digitalWrite(SW1_PIN, HIGH);
        digitalWrite(SW2_PIN, HIGH);
        digitalWrite(SW3_PIN, HIGH);
        analogWrite(FADE_LIGHT_PIN, 1023);
    }

  SwitchOnAngleRange(SW1_PIN, 180, 245);
  SwitchOnAngleRange(SW2_PIN, 235, 300);
  SwitchOnAngleRange(SW3_PIN, 290, 350);
   
   
  }
}