The module is a 4 digit clock with 4 points of positive digital, only 12 signal lines can make four 8-segment LED. Module features are as follows: Display of male red for the four digital tube Adjustable digital tube 8 gray Level control interface for 5V or 3.3V, screws positioning holes for easy installation Control Interface: A total of 12 pins (A,B,C,D,E,F,G,H, SEG1, SEG2, SEG3, SEG4). It based on multiplexing connection between all 4 digits.

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