IB Computer Science - Hardware

Flashcards for Lesson 1

Hardware

The physical components of a computer system and the actual electrical parts that work in unison that executes programs that a software requires.

Peripherals

The expernal devices that connect to and work with the computer

Outline the purpose of the Memory Data Register (MDR)

The Memory Data Register holds the data needed for the transferred from the addesses in the Memory Adressess Registers.

Outline the role of the Arethmetic Logic Unit

The ALU performs arithmetic and logical operations. This includes basic calculations like addition and subtraction, as well as logical operations like comparing numbers.

Outline the purpose of the Memory Addresss Register (MAR)

The Memory Address Register holds the addresses of data that need to be reas or written to the MDR.

Distinguish between two types of primary memory

Two types of primary memory are Random Access Memory (RAM) and Read-Only Memory (ROM). RAM is volatile memory, meaning its data is lost when the power is turned off, whereas ROM is non-volatile, meaning it retains data even without power.

Distinguish between random access memory (RAM) and read only memory (ROM)

RAM is volatile memory, meaning its data is lost when power is turned off, while ROM is non-volatile and retains data permanently. RAM is used for temporary storage of active programs and data, whereas ROM stores permanent instructions, such as firmware and system boot information. RAM allows data to be read and written, while ROM only allows reading (though some types like EEPROM can be modified).

Identify three functions of the control unit (CU) in the central processing unit (CPU)

The CU directs the operation of the processor. It fetches instructions from the RAM memory and decodes them to determine the required operations. Lastly, the CU coordinates and controls the execution of instructions by sending appropriate signals to different parts of the CPU.

Explain how cache memory affects the system performance

Cache memory is a fast and non-persistent memory that stores data and instructions that are frequently used and accessed. The CPU’s access to RAM and Hard Drives is slow compared to access its own cache, therefore a CPU contains a cache for frequently accessed data/instructions. This improves overall system performance by minimizing the time the CPU spends waiting for data from the main memory.

Explain the roles of the data bus and the address bus in the machine instruction cycle

Data buses are used as a communication channel that carries the actual data being processed by the CPU, memory and other peripherals whereas an addess bus is a communication channel that carries the addresses of memory locations where data is to be read from or written to. It specifies the location in memory that the CPU wants to access.

The machine instruction cycle is a sequence of actions that a central processing unit (CPU) performs to execute each machine code instruction in a program. State where the program is held.

The program is held in the primary memory which is the RAM (Random Access Memory)

State the part of the central processing unit (CPU) that performs the decoding.

The control unit (CU) in the component of the Central Processing Unit which decodes instrictions fetched from the RAM for the CPU to process and execute.

State the part of the central processing unit (CPU) that is responsible for carrying out calculations.

The Arithmetic Logic Unit (ALU)

State the purpose of the persistent storage on the computer

The purpose of persistent storage is to permanently store data and programs evend when the computer is powered off. This ensures that important software such as the operating system and software remain available for future uses. Some examples of persistent storage are Solid-State flash drives (SSDs) and Hard Drives (HDDs)

Define the term periperals

Periperals are external devices that connect to and work with the computer. some examples of this are headphones and monitors.