Datasheet

Next up you will have to adjust whatever code you have to select the correct multiplexed
port!
Make sure before you query from the sensor that you call tcaselect to get the right one
#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_HMC5883_U.h>
#define TCAADDR 0x70
/* Assign a unique ID to this sensor at the same time */
Adafruit_HMC5883_Unified mag1 = Adafruit_HMC5883_Unified(1);
Adafruit_HMC5883_Unified mag2 = Adafruit_HMC5883_Unified(2);
void displaySensorDetails(Adafruit_HMC5883_Unified *mag)
{
sensor_t sensor;
mag->getSensor(&sensor);
Serial.println("------------------------------------");
Serial.print ("Sensor: "); Serial.println(sensor.name);
Serial.print ("Driver Ver: "); Serial.println(sensor.version);
Serial.print ("Unique ID: "); Serial.println(sensor.sensor_id);
Serial.print ("Max Value: "); Serial.print(sensor.max_value); Serial.println(" uT");
Serial.print ("Min Value: "); Serial.print(sensor.min_value); Serial.println(" uT");
Serial.print ("Resolution: "); Serial.print(sensor.resolution); Serial.println(" uT");
Serial.println("------------------------------------");
Serial.println("");
delay(500);
© Adafruit Industries
https://learn.adafruit.com/adafruit-tca9548a-1-to-8-i2c-multiplexer-
breakout
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