Many electronic devices use two or more than two seven segment displays to display their output. The two seven segment displays can be connected in two ways. One way is to connect the two displays to the two ports of the microcontroller. However this is not a good way, as this will block all the ports and we cannot use microcontroller for any other purpose. To overcome this problem, we use multiplexing of seven segment display. In multiplexing we use the concept of persistence of vision i.e., human brain cannot differentiate between two events occurring at a time difference of less than .04 sec. In this case the two digits are displayed one after the other so fast that the human brain cannot detect the difference. Although only one digit is displayed at a time it appears as a two digit number. The circuit presented here demonstrates the above principle in form of a counter which counts from 0 to 99 with a small delay. Schematic diagram for interfacing multiple 7 segment ...
