Data transfer modes in digital systems Systems that move multiple bits at the same instant across several conductors are said to transfer data ________.
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Aserially
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Bsequentially
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Cin parallel
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Dboth serially and sequentially
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Easynchronously only
Answer
Correct Answer: in parallel
Explanation
Introduction / Context:Digital designs use two fundamental data transfer modes: serial and parallel. Correctly identifying the mode from its description is essential for understanding bus design, throughput, and cabling trade-offs in computers, microcontrollers, and communication links.
Given Data / Assumptions:
- Parallel transfer uses multiple conductors to carry multiple bits simultaneously.
- Serial transfer uses one lane (or a differential pair) to send bits sequentially in time.
- “At the same instant” implies simultaneous multi-bit transfer.
Concept / Approach:The phrase “move multiple bits at the same instant across several conductors” is the defining characteristic of parallel transfer. This is common on internal buses (e.g., an 8-bit data bus) where wiring cost and skew can be managed over short distances. Serial links dominate long-distance/high-speed connections where pin count must be minimized.
Step-by-Step Solution:
Identify key phrase: simultaneous multi-bit movement.Map this to parallel transfer by definition.Exclude serial because it is bit-by-bit over time.Select “in parallel.”Verification / Alternative check:Classic textbooks distinguish parallel (wider buses, higher instantaneous width) and serial (narrow link, serialized bits). Timing diagrams of parallel buses show several lines toggling in the same clock window for a word transfer.
Why Other Options Are Wrong:
- Serially: Bits are not transferred simultaneously; they are sequenced.
- Sequentially: Ambiguous phrase; could apply to control steps, not to the physical transfer width.
- Both serially and sequentially: Mixes concepts; not the definition in the prompt.
- Asynchronously only: Synchronization is orthogonal to parallel/serial classification.
Common Pitfalls:Confusing differential signaling (two wires) with parallel transfer; a differential pair still carries one serialized bit stream per pair.
Final Answer:in parallel