Peripherals and Buses In computer I/O, a “daisy chain” arrangement is primarily used for what purpose?
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AConnecting a number of controllers to a single device
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BConnecting a number of devices to a single controller
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CInterconnecting multiple controllers and multiple devices in a full mesh
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DAll of the above
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ENone of the above
Answer
Correct Answer: Connecting a number of devices to a single controller
Explanation
Introduction / Context:Daisy chaining is a classic hardware technique where multiple peripherals share a single controller or bus using a serial or cascading connection. It appears in interfaces such as SCSI (older generations), IEEE-488 (GPIB), and some modern display/Thunderbolt topologies.
Given Data / Assumptions:
- Daisy chain implies a sequence: controller → device 1 → device 2 → …
- Only one controller initiates bus transactions; devices respond per addressing/priority rules.
- We are not describing a many-controller mesh network.
Concept / Approach:Identify the topology: a chain off a controller, often with address or ID assignment and termination rules. Evaluate which option correctly describes that topology.
Step-by-Step Solution:Recognize “daisy chain” as a single-controller, multiple-device arrangement.Confirm that each device links to the next, sharing the bus and signals.Conclude that the accurate description is connecting many devices to one controller.
Verification / Alternative check:Historically, SCSI chains required terminators at physical ends and unique device IDs, precisely matching “many devices on one controller”. GPIB allows multiple instruments on one controller in a chain or star-like formation.
Why Other Options Are Wrong:Connecting many controllers to one device (Option A) reverses the relationship.A full mesh of multiple controllers and devices (Option C) is not a daisy chain; it needs switches or hubs.“All of the above” is invalid because only one description fits.
Common Pitfalls:
- Confusing daisy chaining with hub/switch-based star networks.
- Forgetting required termination or unique addressing in chained buses.
Final Answer:Connecting a number of devices to a single controller.