Jul 3, 2019
MQ135 Gas Sensor with ESP8266 and ST7789 SPI Display
MQ135 is a Gas sensor. It works on analogue and digital pins with Arduino boards. It gives analogue value in PPM of Air Quality. When we use a digital pin, it gives on signal at a particular value of analogue. This can be adjusted via potentiometer. So, you can also detect a particular gas without using any microcontroller. Just seeing a green LED, you can know it. Read the full article