Priority encoder behavior — what appears at the outputs when multiple inputs may be active? Choose the best description of the output code for a priority encoder.

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Solve this multiple-choice question and choose the correct option.

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Introduction / Context: Encoders compress multiple input lines into a smaller set of output lines. Priority encoders add arbitration: when more than one input is active, they choose the one with the highest priority and report its index as a binary code. Given Data / Assumptions: Multiple inputs may assert simultaneously. A static priority is predefined (e.g., input 7 over input 6, etc.). Only one encoded value is presented at a time. Concept / Approach: The function of a priority encoder is to output the binary number that identifies the highest-priority active input. Some devices also assert a “valid” output to indicate that at least one input is active, and may provide enable outputs for cascading. Step-by-Step Solution: Detect active inputs.Resolve conflicts via fixed priority order.Encode the index of the highest-priority active line.Drive outputs with that code; optionally assert “valid”. Verification / Alternative check: Check a part like 74HC148: output equals the index of the highest-numbered active input (with active-LOW conventions handled). Why Other Options Are Wrong: Lowest-priority: Opposite of specification.Population count: That is a different function (counting ones).Parity: Encoders do not compute parity unless explicitly designed to. Common Pitfalls: Forgetting about active-LOW input/output conventions and enable pins. Final Answer: Binary code corresponding to the highest-priority asserted input

Priority encoder behavior — what appears at the outputs when multiple inputs may be active? Choose the best description of the output code for a priority encoder.

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