Hello Everyone.

This istructables is for the beginners who have entered into the Arduino ecosystem

In this instructable,i am gonna cover a few topics about DHT11 Humidity and Temperature Sensor and Multiplexing 4 7-Segment Displays.

So,Lets begin!

## Step 1: Parts Required:-

For this instructable to make,you require these parts:-

1. 1 X Arduino Microcontroller(UNO,Mega,Pro MIni etc.)

2. 4 X 7-Segment Display(Common Anode)

3. 1 X DHT11 Humidity And Temperature Sensor

4. Some Jumper Wires

5. Little Bit Knowledge About Multiplexing

## Step 2: Circuit Diagram and CODE

For this circuit,you have to multiplex the 4 segment displays which means all the led pins of the segment displays will be connected in series and then connected to arduino digital pins but the respective common ground pins of the segment displays will be connected individually to arduino digital pins.

These saves us the complications and there are not so many digital pins in arduino UNO(the board that i am using).

You can also use Shift Registers to control many segment displays.

In the circuit diagram all the LED Segment pins of the 4 segment displays i.e A,B,C,D,E,F,G are connected with each other i.e A=A1+A2+A3+A4,B=B1+B2+B3+B4 etc.

Just wire according to the circuit diagram and upload the code given below.

## Step 3: Its Done!

After following the above steps,you can be able to view Temperature and Humidity on your Segment Displays.
The only problem is that the temperature display displays the temperature and then it is switched off for 1 sec to display the humidity on the other segment displays.
Hoping to solve that problem ASAP.
<p>Hi guys, I see that in this Instructable and a few others , on mux'ing, there are no current limiting resistors between the micro and the display. I have thought that that it was good engineering practice to pretect the micro with resistors, should something go wrong. </p><p>Comments please.</p>
It does not possess a big risk to Arduino but you can apply current limiting resistors as a good engineering rule.
<p>I agree... Most &quot;beginner&quot; Arduino projects are simply &quot;forget&quot; the necessity of current limiting resistors. (Meanwhile many sources states that the lack of these are not a real risk at all.) BTW, I suggest to use 220 R (or similar) resistors on each cathode line (pins D2~D8). For the next step, a shift register may help a lot to use less pins and better coding (MAX 7221/7219 for example).</p>
Which DHT library are you using?
DHT11
<p>I bought the sensor for a hydroponics project but was at a loss where to start. Now I know! Great ible!</p>
thanks!