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Codiode/Problems/Combinational Logic

Unreachable State Optimization

MediumLogic CircuitDebug

The next-state combinational logic calculates the upcoming state of a control finite state machine based on enable and mode signals.

Expected behavior:

| En | M1 | M2 | N2 | N1 | N0 | |------|------|------|------|------|------| | 0 | 0 | 0 | 0 | 0 | 0 | | 0 | 0 | 1 | 0 | 0 | 0 | | 0 | 1 | 0 | 0 | 0 | 0 | | 0 | 1 | 1 | 0 | 0 | 0 | | 1 | 0 | 0 | 1 | 0 | 0 | | 1 | 0 | 1 | 1 | 0 | 0 | | 1 | 1 | 0 | 1 | 1 | 0 | | 1 | 1 | 1 | 1 | 0 | 1 |

Simulation shows outputs N2=1, N1=0, N0=0 for input En=1, M1=1, M2=1. The transition to state 5 (101) fails and the machine incorrectly targets state 4 (100). Inspect the circuit and correct the fault.

Constraints

  • Do not alter the logic paths that successfully compute states 0, 4, or 6
  • Use only basic logic gates (AND, OR, NOT)
  • Maintain the existing input and output port definitions

Topics

fsmlogic-optimizationdebug

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Place the gates, wire them up and watch the signals settle. Every submission runs on the same simulation engine that grades it.

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