Tutorial How to 4-Digit Display Interface With Arduino UNO | tecno4 | Scoop.it
From www.instructables.com - April 14, 2018 1:55 AM
A 4-digit 7-segment LED display has 12 pins. 8 of the pins are for the 8 LEDs on a 7 segment display, which includes A-G and DP (decimal point). The other 4 pins represent each of the 4 digits from D1-D4.