It always a good idea to test whether a device is working properly or not if that component have a very large number of pins. In this project, i have tested my 4 digit 7 segment 14 pin display. All the 7 segment will display 0 to 9 at the same time.

Code for both common anode and common cathode 4 digit 7 segment display will be provided in this project.

To learn how 7 segment display work click here.

Component required

Arduino - https://amzn.to/32jAMUA
breadboard - https://amzn.to/3kdp4Rt
Jumper wires - https://amzn.to/3iqdBxM
9 X Resistor 220 ohms - https://amzn.to/2ZuPNRN
7 segment display - https://amzn.to/35p4wS5

Step 1: Pin Diagram of 14 Pin Display

14 pin display pin diagram was not available online in clear manner so i decided to draw it manually.

In 14 pin display we have extra 2 pins for : between 4 digit 7 segment display pin 7 is com of these : and pin 8 should be connected to a GPIO pin of Arduino.

If it is a common anode display then value of all the common terminals HIGH . In case of common cathode keep it LOW in your code.

Step 2: Circuit Schematic

This circuit will work for both common anode and common cathode display

Step 3: Arduino Code

If it is a common anode display then value of all the common terminals(D1 to D4) HIGH and COM(A1) HIGH . In case of common cathode keep it LOW in your code.