Ring counters If the output of a shift register is fed back to the input a ring counter results The data pattern contained within the shift register will recirculate as long as clock pulses are applied For example the data pattern will repeat every four clock pulses in the figure below However we must load a data pattern

Ring counters

 

If the output of a shift register is fed back to the input. a ring counter results. The data pattern contained within the shift register will recirculate as long as clock pulses are applied. For example, the data pattern will repeat every four clock pulses in the figure below. However, we must load a data pattern. All 0"s or all 1"s doesn"t count. Is a continuous logic level from such a condition useful?

 

We make provisions for loading data into the parallel-in/ serial-out shift register configured as a ring counter below. Any random pattern may be loaded. The mostgenerally useful pattern is a single 1.

 

Loading binary 1000 into the ring counter, above, prior to shifting yields a viewable pattern. The data pattern for a single stage repeats every four clock pulses in our 4-stage example. The waveforms for all four stages look the same, except for the one clock time delay from one stage to the next. See figure below.