ESPIoTBase/src/i2c.ino

#ifdef ENABLE_I2C_INTERFACE
void i2cscan() {
  byte error, address;
  int nDevices;
  
  snprintf(logBuf, LOG_BUFFER_SIZE, "Scanning I2C devices...");
  sendLog(logBuf, LOGLEVEL_INFO);
 
  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("  !");

      snprintf(logBuf, LOG_BUFFER_SIZE, "    device found at address 0x%x", address);
      sendLog(logBuf, LOGLEVEL_INFO);
 
      nDevices++;
    }
    else if (error==4)
    {
      //Serial.print("    unknown error at address 0x");
      //if (address<16)
      //  Serial.print("0");
      //Serial.println(address,HEX);

      snprintf(logBuf, LOG_BUFFER_SIZE, "    unknown error at address 0x%x", address);
      sendLog(logBuf, LOGLEVEL_INFO);
    }    
  }
  if (nDevices == 0) {
    //Serial.println("No I2C devices found\n");
    snprintf(logBuf, LOG_BUFFER_SIZE, "    No I2C devices found.");
    sendLog(logBuf, LOGLEVEL_INFO);
  }
  else {
    //Serial.println("done\n");
    snprintf(logBuf, LOG_BUFFER_SIZE, "    DONE!");
    sendLog(logBuf, LOGLEVEL_INFO);
  }   
} // i2cscan()
#endif