Then we can see that BCD counters are binary counters that count from 0000 to 1001 and then resets as it has the ability to clear all of its flip-flops after the ninth count. If we connect a pushbutton switch (SW1) to clock input CLKA, each time the pushbutton switch is released the counter will count by one. If we connected light emitting diodes (LED’s) to the output terminals, QA, QB, QC and QD as shown, we can view the binary coded decimal count as it takes place.