Example Code for Arduino-Read via I2C

Hardware Preparation

• DFRduino UNO R3 (or similar) x 1
• Alcohol sensor x1
• Jumper wires

Software Preparation

• Arduino IDE
• Download and install the DFRobot Alcohol Sensor library. (About how to install the library?)

Wiring Diagram

Other Preparation Work

• It is recommended to preheat for 24~48 hours when powering up the module for the first time.
• The alcohol concentration during preheat will become stable 3 minutes later so please ignore the data generated within that time.
• Organic solvents like essential balm(tiger balm) or Florida Water will damage the sensor, so please do not use them for testing.
• Connect the sensor with Arduino as shown above. A Gravity I/O expansion board will make it more easier.
• Dial the select switch on the sensor to I2C.
• The default I2C address is 0x75, ADDRESS_3 in code. If you want to change the address, first configure the hardware I2C address via the DIP switch on the module, and then revise I2C address define ADDRESS_X in the sample code. The relation between DIP switch and I2C address is shown below:
  • ADDRESS_0：0x72, A0=0, A1=0
  • ADDRESS_1：0x73, A0=1, A1=0
  • ADDRESS_2：0x74, A0=0, A1=1
  • ADDRESS_3：0x75, A0=1, A1=1
• Download and install DFRobot Alcohol Sensor library
• Open Arduino IDE, upload the following codes into Arduino UNO.
• Open Arduino serial monitor, set baud rate to 9600, then check the result.

Sample Code

/*!
 * @file  readAlcohol.ino
 * @brief Reading Alcohol concentration, A concentration of one part per million (PPM).
 * @n step: we must first determine the iic device address, will dial the code switch A0, A1 (ADDRESS_0 for [0 0]), (ADDRESS_1 for [1 0]), (ADDRESS_2 for [0 1]), (ADDRESS_3 for [1 1]).
 *
 * @copyright   Copyright (c) 2010 DFRobot Co.Ltd (http://www.dfrobot.com)
 * @licence     The MIT License (MIT)
 * @author      ZhixinLiu([email protected])
 * @version     V1.0
 * @date        2020-09-09
 * @get         from https://www.dfrobot.com
 * @url         https://github.com/dfrobot/DFRobot_Alcohol
 */

#include "DFRobot_Alcohol.h"

#define COLLECT_NUMBER   5                      // collect number, the collection range is 1-100
#define ALCOHOL_I2C_ADDRESS ADDRESS_3
/*   iic slave Address, The default is ADDRESS_3
       ADDRESS_0               0x72             // i2c device address
       ADDRESS_1               0x73
       ADDRESS_2               0x74
       ADDRESS_3               0x75
*/
DFRobot_Alcohol_I2C Alcohol(&Wire ,ALCOHOL_I2C_ADDRESS);

/*
#ifdef ESP_PLATFORM
  // ESP32 user hardware uart
  // RX io16
  // TX io17
  DFRobot_Alcohol_UART Alcohol(&Serial2 ,9600);
#else
  // Arduino user software uart
  // RX io10
  // TX io11
  SoftwareSerial              mySerial(10 ,11);
  DFRobot_Alcohol_UART Alcohol(&mySerial ,9600);
#endif
*/

void setup() 
{
  Serial.begin(9600);
  while(!Alcohol.begin())
  {
    Serial.println("NO Deivces !");
    delay(1000);
  }
  Serial.println("Device connected successfully !");

/*  Set iic mode, active mode or passive mode
      MEASURE_MODE_AUTOMATIC            // active  mode
      MEASURE_MODE_PASSIVE              // passive mode
*/
  Alcohol.SetModes(MEASURE_MODE_AUTOMATIC);
}


void loop() 
{
/*  Smooth data collection
      COLLECT_NUMBER                    // The collection range is 1-100
*/
  float alcoholConcentration = Alcohol.ReadAlcoholData(COLLECT_NUMBER);
  if(alcoholConcentration == ERROR)
  {
    Serial.println("Please check the connection !");
  }else{
    Serial.print("Alcohol concentration is ");
    Serial.print(alcoholConcentration);
    Serial.println(" PPM.");
  }
  delay(1000);
}

Result

Open the serial monitor, preheat 3 minutes and check the final data.

Note:

1. There may be data drift appearing.
   
2. Electrochemical type sensors need to be preheated for 24~48 hours when powering up for the first time.