Question

A Mealy sequential circuit has one input X and two outputs Z1Z2. The circuit produces output Z1=1 whenever the input sequence 101 is completed and produces output Z2=1 whenever the input sequence 1010 is completed. Derive the state graph and table.

Answer 1

A Mealy sequential circuit is a type of finite state machine where the outputs depend on both the current state and the inputs. By analyzing the input sequence and the desired outputs, we can derive the state graph and table for the circuit.

Step-by-step explanation:

A Mealy sequential circuit is a type of finite state machine where the outputs depend on both the current state and the inputs. In this case, we have one input X and two outputs Z1 and Z2.

To derive the state graph and table, we need to consider the possible states and transitions based on the input and current state. Since output Z1=1 whenever the input sequence 101 is completed, let's start with the initial state and analyze the transitions:

• State A: Initially, no inputs are completed. If input X=1, we transition to state B. If X=0, we stay in state A.
• State B: We have one input (1) completed. If X=0, we transition to state C. If X=1, we stay in state B.
• State C: We have two inputs (10) completed. If X=1, we transition to state D. If X=0, we stay in state C.
• State D: We have three inputs (101) completed. Here, Z1=1, so we output Z1=1 and transition back to state A regardless of the next input X.

Based on the information above, we can draw the state graph and construct the state table, which includes the current state, the input, the next state, and the outputs:

State Table:

Current StateInputNext StateZ1Z2A0A00A1B00B0C00B1B00C0C00C1D10D0/1A01