Draw the circuit daigram for the twisted - tail ( Jonhson) counter consisting of 4 Flip flops (A,B,C,D) with the following excitations: Da='Qe, Db=Qa,Dc=Qb,De=Qc.Assume the flip flop are cleared intially .
1. Obtain the compete state diagram showing both used and unused states and transisition . Is it a self correcting design?
2. If the design is not self correcting modify it to botain a self correcting design. Show the work and draw the circuit diagram for the counter with self correction.
3. Desgin the state decoder which provides a high logic level at only one output at a time. Draw the circuit diagram for the decoder.