Final answer:
The ability of a controller to communicate with the main memory is known as memory access, which is crucial for fetching and executing instructions in a computer system. This enables the digital computers to process large amounts of information efficiently, a capability central to the function of the Control Unit in the von Neumann architecture.
Step-by-step explanation:
The ability of a controller to communicate with the main memory is called memory access. This term describes the process by which the processor of a digital computer retrieves (reads) and writes (stores) data to and from the main memory. Memory access is fundamental in computer architecture because it essentially dictates how data flows between the processor and the memory, and, as such, is a critical factor in determining the overall speed and efficiency of the computer system.
The device made it possible for digital computers to efficiently process large amounts of information is the von Neumann architecture, which includes a Control Unit (CU). The CU orchestrates the fetching (reading), decoding, and execution of instructions by directing coordinated operations using its control signals. This involves accessing both instructions and data from memory, highlighting the importance of efficient memory access by the control unit for the performance of complex computing tasks.