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murych/i2c_scanner.ino

Forked from tfeldmann/i2c_scanner.ino
Created November 18, 2019 12:10
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  1. @tfeldmann tfeldmann created this gist Apr 18, 2013.
    80 changes: 80 additions & 0 deletions i2c_scanner.ino
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,80 @@
    // --------------------------------------
    // i2c_scanner
    //
    // 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 known.
    // 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 <Wire.h>


    void setup()
    {
    Wire.begin();

    Serial.begin(9600);
    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.
    Wire.beginTransmission(address);
    error = Wire.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
    }