AN014 Tracker I2C Scanner

You can download the files associated with this app note as a zip file.

The code (tracker-i2cscanner.cpp) and pre-built binary for 1.5.4-rc.1 or later (tracker-i2cscanner.bin) can be found in the Github repository.

Or you can copy and paste the code below:

// --------------------------------------
// i2c_scanner
//
// http://playground.arduino.cc/Main/I2cScanner
//
// Version 1
//    This program (or code that looks like it)
//    can be found in many places.
//    For example on the Arduino.cc forum.
//    The original author is not know.
// Version 2, Juni 2012, Using Arduino 1.0.1
//     Adapted to be as simple as possible by Arduino.cc user Krodal
// Version 3, Feb 26  2013
//    V3 by louarnold
// Version 4, March 3, 2013, Using Arduino 1.0.3
//    by Arduino.cc user Krodal.
//    Changes by louarnold removed.
//    Scanning addresses changed from 0...127 to 1...119,
//    according to the i2c scanner by Nick Gammon
//    http://www.gammon.com.au/forum/?id=10896
// Version 5, March 28, 2013
//    As version 4, but address scans now to 127.
//    A sensor seems to use address 120.
//
//
// This sketch tests the standard 7-bit addresses
// Devices with higher bit address might not be seen properly.
//

#include "Particle.h"

SYSTEM_MODE(MANUAL);

void setup()
{
    Serial.begin(9600);

    waitFor(Serial.isConnected, 15000);
    delay(1000);

    pinMode(CAN_PWR, OUTPUT);
    digitalWrite(CAN_PWR, HIGH);
    delay(500);

    Wire3.begin();

    Serial.println("\nI2C Scanner");
}


void loop()
{
    byte error, address;
    int nDevices;

    Serial.println("Scanning...");

    nDevices = 0;
    for(address = 1; address < 127; address++ )
    {
        // The i2c_scanner uses the return value of
        // the Write.endTransmisstion to see if
        // a device did acknowledge to the address.
        Wire3.beginTransmission(address);
        error = Wire3.endTransmission();

        if (error == 0)
        {
            Serial.print("I2C device found at address 0x");
            if (address<16)
                Serial.print("0");
            Serial.print(address,HEX);
            Serial.println("  !");

            nDevices++;
        }
        else if (error==4)
        {
            Serial.print("Unknow error at address 0x");
            if (address<16)
                Serial.print("0");
            Serial.println(address,HEX);
        }
    }
    if (nDevices == 0)
        Serial.println("No I2C devices found\n");
    else
        Serial.println("done\n");

    delay(5000);           // wait 5 seconds for next scan
}

Author: Rick