New version of MAX7219 based 4-digit serial seven segment LED display

This (SPI7SEGDISP4.40-1R) is a revised version of the previous SPI seven segment LED display (4 digit) board that displayed numerals and decimal points. The new version has a better quality seven segment LED display (LTC-4727JS) with three extra LED segments, as shown below. The additional colon segments are useful in projects where you need to display time (HH:MM or MM:SS).
The common cathode terminals (Digit 1, Digit 2, Digit 3, and Digit 4) of the four seven segment digits are connected to D3, D2, D1, and D0 pins of MAX7219 driver chip. The common cathode pin 4 of LTC-4727 goes to D4 pin of MAX7219. So, in order to turn on L1, L2, and L3 segments, D4 digit select pin of MAX7219 should be active. Here’s an example that shows how to interface this module with an Arduino board usinf the Led Control library.

#include "Led Control. h"
// Arduino Pin 7 to DIN, 6 to Clk, 5 to LOAD, no. of devices is 1
Led Control lc=Led Control(7,6,5,1);
void setup()
 // Initialize the MAX7219 device
  lc.shutdown(0,false);   // Enable display
  lc.setIntensity(0,10);  // Set brightness level (0 is min, 15 is max)
  lc.clear Display(0);     // Clear display register
void loop()
  lc.setDigit(0,0,4,true); // Display 4 to Digit 4, and turn DP on
  lc.setDigit(0,1,3,true); // Display 3 to Digit 3, " "
  lc.setDigit(0,2,2,true); // Display 2 to Digit 2, " "
  lc.setDigit(0,3,1,true); // Display 1 to Digit 1, " "
  lc.setDigit(0,4,7,true); // Turns L1, L2, and L3 on

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