Computer Data Conversion - SS2 ICT Past Questions and Answers - page 2
Which register assists in decoding instructions and fetching data from memory?
Accumulator Register
Memory Address Register (MAR)
Program Counter (PC)
Instruction Register (IR)
What role do index registers play in memory access?
They store intermediate arithmetic results
They hold the memory address of data to be read or written
They provide offsets for array or table indexing
They store the next instruction to be fetched
The main purpose of the accumulator register is to:
Hold the memory address of data
Temporarily store data during memory transfers
Store intermediate arithmetic and logical results
Keep track of program sequencing
Which type of memory is responsible for bridging the speed gap between the CPU and main memory?
Accumulator memory
Cache memory
Virtual memory
Memory Buffer Register (MBR)
What is the purpose of the Instruction Register (IR)?
To store intermediate arithmetic and logical results
To hold the memory address of data being transferred
To keep track of program sequencing
To hold the current instruction being executed
Describe the role of index registers in optimizing memory access during data retrieval.
Index registers are specialized registers used to improve the efficiency of memory access during data retrieval. When accessing data from arrays, tables, or other structured data formats, index registers store offset values that determine the starting point for accessing the desired data. By utilizing index registers, the CPU can calculate memory addresses more quickly, reducing the need for repetitive calculations during each access. This speeds up the retrieval process and enhances overall program performance.
How does the Program Counter (PC) contribute to the correct sequencing of instructions in a program?
The Program Counter (PC) plays a pivotal role in ensuring the correct sequencing of instructions in a program. It holds the memory address of the next instruction to be fetched and executed. When the CPU finishes executing an instruction, the PC is incremented to point to the next memory address, indicating the subsequent instruction. This sequential advancement of the PC guarantees that instructions are executed in the correct order, maintaining the program's intended flow.
Explain the significance of the Memory Buffer Register (MBR) in memory operations
The Memory Buffer Register (MBR) serves as a temporary storage unit during memory operations. When data is being transferred between the CPU and main memory, it's first placed in the MBR. This allows for smoother communication between the relatively fast CPU and the comparatively slower main memory. The MBR acts as a buffer, holding the data until the CPU is ready to process it or until the data is transferred to or from the main memory. This buffering helps bridge the speed difference and ensures efficient data transfer.
Compare and contrast the functions of the Memory Address Register (MAR) and the Memory Buffer Register (MBR) in relation to main memory operations
Memory Address Register (MAR): The MAR holds the memory address of the location from which data is to be read or to which data is to be written. It acts as a pointer that helps the CPU identify the specific location in the main memory.
Memory Buffer Register (MBR): The MBR temporarily holds the data being transferred between the main memory and the CPU. It serves as a buffer to accommodate data as it's moved to or from the main memory.
While both registers are involved in main memory operations, their functions differ:
The MAR focuses on addressing, specifying the memory location.
The MBR focuses on the actual data being transferred, providing temporary storage.
Together, these registers facilitate efficient data movement between the CPU and main memory during read and write operations.