Monday, January 1, 2024

Explanation of CRC Operation: Polynomial Division, Shift Register, and Comparison (video)

 Here is a video explaining the mechanics of Cyclic Redundancy Check computations, including:

  • An example of the polynomial division approach
  • An example of the XOR-feedback shift register approach
  • A step-by-step comparison of how the polynomial division and shift register approaches are actually doing exactly the same computation.
If you've ever wondered why it is that a shift register and polynomial division end up with the same result, this video explains it.

FULL VIDEO:   YouTube |

The full video consists of these four parts: (YouTube Play List):
  • Part 1: Example CRC Division to compute check value (YouTube 4:25)
  • Part 2: Example CRC Validation via Polynomial Division (YouTube 3:30)
  • Part 3: Example CRC Computation via Hardware Shift Register (YouTube 8:10)
  • Part 4: Comparison of CRC Polynomial Division and Hardware Shift Register (YouTube 6:21)

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