Hello,
I have used single 7 segment to display digits from 1-9
Now I am using 3 (common 7 segments)
I have a value (x, anything between 0-999 ) I want to display the value using 7 segments . In case of single digit 0-9 its easy ( turning pins HIGH and LOW for just ten digits ) . but how would I do it for such a large extent (0-999).
Easy way is to use a transistor with each common anode (PNP) or common cathode (NPN) and enable one digit at a time for a 5-10 mS each, or less if you think you can see it flickering.
Cycle thru all of them, persistence of vision (POV) will fool your eye/brain into seeing them as being on all the time, just like a TV.
Multiplexing them like CrossRoads says is indeed a easy way. And instead of 3x8 pins you only need 8 + 3 pins to drive it. And you can make a program to do that all by yourself. Or [/s]be lazy ~~save the trouble and use a library like SevSeg Arduino Playground - HomePage