Chapter 1 - Introduction to Computer Systems - Flashcards

Flashcards covering key concepts from Chapter 1: introduction to computer systems, including definitions of computer architecture, organization, interconnection structures, memory types, caching, the Von Neumann model, I/O, and related topics.

What is a computer?

An electronic device that manipulates information (data); can store, retrieve, and process data; receives data and, according to a predetermined program, performs operations to produce results.

What does computer architecture refer to?

A set of attributes of a system as seen by the programmer, including the instruction set, number of bits used to represent data types, I/O mechanism, and memory addressing techniques.

What does computer organization cover?

The hardware components and their interconnections, interfaces between the computer and peripherals, and memory technology; details are often transparent to the programmer.

Name the basic functions of a computer.

Data processing (arithmetic/logic), data storage, data movement (I/O), and control.

What is interconnection structure in a computer system?

The collection of paths connecting the components (CPU, memory, I/O); its design depends on the exchanges that must be made among modules.

What is a bus in a computer system?

A communication pathway that connects two or more devices; a shared transmission medium consisting of multiple lines for data, address, and control.

What is a system bus?

A bus that connects the CPU, memory, and I/O devices; typically 50–100 lines and includes data, address, and control lines.

What are the three basic computer functional units?

The CPU (which contains the ALU and registers) and the Control Unit; effectively, the CPU comprises the ALU, registers, and the control logic.

What are the major components of the IAS computer structure?

Central Processing Unit (CPU) including the Arithmetic-Logic Unit, Main Memory, Program Control Unit, and I/O Equipment.

What is the stored-program concept?

The idea that data and the program (instructions) are stored in the same memory and executed sequentially.

What is memory/main memory used for?

Used to store instructions or data; data/instructions may be accessed multiple times, so temporary storage is needed.

What is external storage?

Backing store or secondary memory used for permanent storage of large quantities of data.

What is Direct Memory Access (DMA)?

Direct memory access allows I/O devices to transfer data to/from memory directly without CPU intervention.

What is DRAM?

Dynamic RAM; slower than SRAM and requires refreshing.

What is SRAM?

Static RAM; faster and used as cache; does not require refreshing.

What is DIMM?

Dual In-Line Memory Module; a memory module containing DRAM chips used in modern systems.

What is CMOS memory?

Memory that stores small, nonvolatile data (e.g., BIOS settings) and persists when the computer is powered off.

What is cache memory?

A high-speed memory between the CPU and main memory that stores data/instructions likely to be used soon; built from SRAM; uses tags to identify data origin.

What is L1 cache?

Primary cache: very fast but small, usually embedded in the processor; typically 2 KB to 64 KB.

What is L2 cache?

Secondary cache: larger than L1; may be on the CPU or a separate chip; typically 256 KB to 512 KB.

What is L3 cache?

Last Level Cache (LLC): larger than L1/L2, located outside the CPU, shared by all cores; typically 1 MB to 8 MB.

What is associative cache mapping?

Any block of main memory can reside in any cache block position.

What is direct cache mapping?

A particular block of main memory maps to a specific cache block.

What is set-associative cache mapping?

Cache is divided into sets; a block of main memory can reside in any line within a specific set.

What is cache hit?

When the required data is found in the cache.

What is cache miss?

When the required data is not in the cache and must be fetched from main memory.

Describe the cache data flow order from memory to CPU caches.

Data flows from main memory (RAM) to L3, then L2, then L1; the CPU checks L1 first and uses it if a hit occurs.

What is fixed-program computer?

A computer whose function is very specific and cannot be reprogrammed (e.g., calculators).