Name the operation: The memory operation that places data on the outputs after a new address is applied is called ________.

Difficulty: Easy

Correct Answer: a read cycle

Explanation:


Introduction / Context:
Memory transactions are named by their data direction and control strobes. When the system wants the contents of a location to appear on the data outputs, it performs a read. Correctly identifying read versus write is critical for designing timing and control logic.



Given Data / Assumptions:

  • An address is driven onto the address bus and stabilized.
  • Control signals select the memory and indicate read (e.g., WE inactive, OE active, CS active).
  • After access time, the memory drives outputs with the stored value.


Concept / Approach:
A read cycle retrieves data from a specified address. In SRAM, this typically requires CS active, WE inactive, and OE active. In DRAM, after RAS/CAS latch row and column with WE high, the selected cell's data appears at the outputs. By contrast, write cycles store data into the addressed location, and refresh cycles restore DRAM charge without presenting new external data for general use.



Step-by-Step Solution:

Apply address and assert selection signals (CS and OE).Ensure write is not requested (WE inactive).Wait for access time; memory drives outputs with stored data.


Verification / Alternative check:
Timing diagrams label tACC and tOE associated with read, whereas write timing references tDW/tWP for data setup and write pulse width.



Why Other Options Are Wrong:

Write cycle: Direction is to memory, not from memory.Refresh cycle: Internal DRAM operation; not a general data readout.Chip select: An enabling signal, not the entire operation.Precharge interval: DRAM internal preparation, not data presentation.


Common Pitfalls:
Assuming that asserting CS alone produces data; OE/WE states also matter.



Final Answer:
a read cycle

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