High to Low Means Logical One | Generated by AI

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Question: In Manchester encoding, a level transition occurs in the middle of each bit duration. What does a transition from high level to low level represent?

Answer:

Based on the provided reference answer, a transition from high level to low level represents a logical 1.

Comprehensive Explanation

Manchester Encoding is a synchronous clock encoding technique used by the physical layer of the Open System Interconnection (OSI) model to encode clock and data of a synchronous bit stream. In this encoding scheme, each bit period is divided into two halves, and a voltage transition occurs in the middle of each bit duration.

Conventions and Ambiguity: It is important to note that there are two common conventions for defining the logic levels in Manchester encoding, which often leads to confusion:

  1. G.E. Thomas Convention:
    • High-to-Low transition: Represents logical 1.
    • Low-to-High transition: Represents logical 0.
  2. IEEE 802.3 (Ethernet) Convention:
    • Low-to-High transition: Represents logical 1.
    • High-to-Low transition: Represents logical 0.

Context for This Question: Since the provided reference answer is 1, this specific question adheres to the G.E. Thomas convention. Therefore, within the context of this exam problem, a transition from high电平 (high level) to low电平 (low level) in the middle of the bit duration signifies a binary 1.

References:


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