ECE 440 - Design Problems

 

1) Develop a circuit with two outputs, Z1 and Z2, with the following output behavior. There is one pair of outputs per clock cycle.

Z1: 0 1 1 0 0 [. . .]

Z2: 1 1 1 1 0 [. . .]

The above sequences repeat indefinitely. Neatly sketch a gate-level schematic showing flip-flops and next state logic.

 

2) Design a Mealy FSM with two inputs, X and Y, one output, Z, and the following behavior. The FSM simultaneously monitors both the X and Y inputs looking for the specific sequences below and asserts Z whenever the last symbol in one or both of the sequences is applied. Sequences are allowed to overlap, e.g., the last symbol in a sequence can serve as the first symbol for another sequence, and there is no timing relationship between the X and Y inputs other than one input bit per clock cycle. Only the state table/graph is needed.

X: 1 0 1

Y: 1 1 1