The finished circuit can display numbers ranging from 0 through 1023, in connection with a 10K preset pot attached to the analog input A0 of the Arduino board. This 4 -digit 7-segment display section ...

With 4*7+2 = 30 units you can make a 4-digit 7-segment clock ... I like it until you realize the MAX7219 is a $9 ... Your last one of these wasn’t the 48 Arduino thing but my 840 segment ...

Just that one contains 4 digits the other 1 digit. Either way, a single max7219 can control 8 digits, either packaged in a single digit ‘display’ or packaged as 4x ‘display’. Report comment ...