Gas detection module MQ-2 MQ-3 MQ-4 MQ-5 MQ-6 MQ-7 MQ-8 MQ-9 MQ-135 each of them 1pcs total 9pcs sensor for arduino kit

Shipping list:

Features:

• Using high-quality dual-panel design,with power indicator and TTL signal output instructions.
• The switching signal having a DO (TTL) output and analog output AO.
• TTL output valid signal is low. ( Low-level signal when the output light can be directly connected to the microcontroller or relay module )
• Analog output voltage with the higher concentration of higher voltage
• There are four screw holes for easy positioning.
• Has a long life and reliable stability
• Rapid response and recovery characteristic

Wiring:

• VCC: positive power supply (5V)
• GND: power supply is negative
• DO: TTL switching signal output

• AO: analog signal output

  NOTE:

  After the sensor is powered, need to warm about 20S, measured data becomes stable, heat sensor is normal

  Size:

  

  Test program:

  Function: This version of the test program supporting

  Use chip: AT89S52

  Crystal: 11.0592MHZ

  Baud rate: 9600

  Compiler Environment: Keil

  [Statement] This procedure is used only for study and reference, please indicate the copyright and author information!

  ************************************************** ******************* /

  / ************************************************* *******************

  Note: 1, when the measured concentration is greater than the set density, single-chip IO port output low

  ************************************************** ******************* /

  # Include // library files

  #define uchar unsigned char // macro definition unsigned char

  #define uint unsigned int // macro definition unsigned int

  / ************************************************* *******************

  I / O definitions

  ************************************************** ******************* /

  sbit LED = P1 ^ 0; // define microcontroller P1 port of the first one (ie P1.0) to indicate the end

  sbit DOUT = P2 ^ 0; // define the microcontroller P2 port first one (ie P2.0) as an input sensor

  / ************************************************* *******************

  Delay function

  ************************************************** ******************* /

  void delay () // delay procedure

  {

  uchar m, n, s;

  for (m = 20; m> 0; m--)

  for (n = 20; n> 0; n--)

  for (s = 248; s> 0; s--);

  }

  / ************************************************* *******************

  The main function

  ************************************************** ******************* /

  void main ()

  {

  while (1) // infinite loop

  {

  LED = 1; // off P1.0 port lights

  if (DOUT == 0) // When the concentration is higher than the set value, the implementation of the Con

  {

  delay (); // delay interference

  When if (DOUT == 0) // determine the concentration higher than the set value, the implementation of the Con

  {

  LED = 0; // P1.0 port lights lit

  }

  }

  }

  }

  / ************************************************* *******************

  End

  ************************************************** ****************** /