In associative memory, the function of the Key Register is to __________.
2025
In associative memory, the function of the Key Register is to __________.
- A.
store the operand used in arithmetic operations
- B.
act as a temporary buffer for read/write operations
- C.
mask specific bits during a match operation
- D.
hold the memory address for data retrieval
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Correct answer: C
In associative memory, the function of the Key Register is to hold the search key or address used for comparison during data retrieval.
Note for more Understanding
Associative Memory (also known as Content-Addressable Memory or CAM) is a specialized hardware memory operating paradigm where data is accessed by searching for specific data contents rather than pointing to a binary memory address.
When performing a parallel search across the entire memory space, three primary architectural registers manage the operation: the Argument Register (A), the Key Register (K), and the Match Register (M).
The Mechanics of the Key Register:
Bit-Level Selection (Masking): The Key Register acts as a bitmask to filter the search criteria. It provides a mechanism to search for a partial match rather than comparing a whole data word.
The 1 and 0 Logic:
If a bit position in the Key Register is set to
1, it signifies that the corresponding bit column in the Argument Register must be compared against all words in memory.If a bit position in the Key Register is set to
0, it signifies that the corresponding bit column is masked/ignored. Whether the memory cell contains a 0 or a 1 at that location will not affect the match status.