Computer Architecture and Organization - Computer Function and Interconnection

Flashcards reviewing computer components, functions, interconnection structures, and PCI Express based on lecture notes.

What are the three key concepts of the von Neumann architecture?

Data and instructions are stored in a single read-write memory, memory is addressable by location regardless of data type, and execution occurs sequentially.

What is a hardwired program?

The result of connecting various computer components in a desired configuration.

What does the instruction interpreter do?

Interprets each instruction and generates control signals.

What is the role of the input module?

Accepts data and instructions, converting them into an internal form.

What is the function of the main memory?

To temporarily store instructions and data.

What is the Memory Address Register (MAR)?

Specifies the address in memory for the next read or write operation.

What is the Memory Buffer Register (MBR)?

Contains data to be written into memory or receives data read from memory.

What is the I/O Address Register (I/OAR)?

Specifies a particular I/O device.

What is the I/O Buffer Register (I/OBR)?

Used for the exchange of data between an I/O module and the CPU.

What are the two primary steps in the instruction cycle?

Fetch and Execute.

What is an instruction cycle?

The processing required for a single instruction.

What is the function of the Program Counter (PC)?

Contains the address of the next instruction pair to be fetched from memory.

What is the function of the Instruction Register (IR)?

Contains the instruction being executed.

What happens during the fetch cycle?

The processor fetches an instruction from memory, guided by the program counter (PC).

Name four categories of actions performed by instructions.

Processor-memory, Processor-I/O, Data processing, Control

What is the Accumulator (AC)?

Temporary storage within the CPU.

What is Instruction address calculation (iac)?

Determine the address of the next instruction to be executed.

What is Instruction fetch (if)?

Read instruction from its memory location into the processor.

What is Instruction operation decoding (iod)?

Analyze instruction to determine type of operation to be performed and operand(s) to be used.

What is Operand address calculation (oac)?

If the operation involves reference to an operand in memory or available via I/O, then determine the address of the operand.

What is Operand fetch (of)?

Fetch the operand from memory or read it in from I/O.

What is Data operation (do)?

Perform the operation indicated in the instruction.

What is Operand store (os)?

Write the result into memory or out to I/O.

What is the purpose of interrupts in a computer system?

To allow other modules (I/O, memory) to interrupt the normal processing of the processor.

What is Direct Memory Access (DMA)?

Allows I/O modules to exchange data directly with memory without involving the processor.

What is a system bus?

A bus that connects major computer components (processor, memory, I/O).

What is the key characteristic of a bus?

It is a shared transmission medium.

What are the three main types of bus lines?

Data bus, Address bus, and Control bus.

What is the purpose of the address bus?

To designate the source or destination of the data on the data bus.

What is PCI Express (PCIe)?

A point-to-point interconnect scheme intended to replace bus-based schemes such as PCI.