This page contains the CBSE class 11 Computer Science with Python chapter 4, Microprocessors and Memory Concepts . You can find the questions/answers/solutions for the chapter 4 of Unit 1 of CBSE class 11 Computer Science with Python in this page.
a)
Define word length of a microprocessor.
b)
Name the two types of Primary Memory.
c)
What is the purpose of System Clock?
d)
Differentiate between CISC and RISC processors.
e)
Why do we use secondary storage? Name any two secondary storage devices.
f)
How is Computer’s internal memory important?
g)
Why is it more appropriate to call RAM as Read-Write memory?
h)
What is the purpose of Cache memory?
i)
Explain in brief the different ports and their purposes.
j)
Distinguish between the following pairs:
a.
Primary memory and Secondary memory
cb.
RAM and ROM
dc.
Bluetooth and Infrared port
Microprocessors and Memory Concepts
a) Define word length of a microprocessor.
The word length of a microprocessor refers to the number of bits that can be processed in a single instruction. It represents the size of data that the internal general-purpose registers can hold during processing. For example, if a microprocessor has a word length of 8 bits, it can process 8 bits of data at a time. The word length is directly related to the processing power of the CPU, and a higher word length generally indicates a more powerful processor.
b) Name the two types of Primary Memory.
The two types of primary memory are:
1.
Random Access Memory (RAM)
2.
Read Only Memory (ROM)
c) What is the purpose of System Clock?
The purpose of the System Clock is to control the pace or speed of the microprocessor. It is an electronic circuit that generates pulses, measured in millions of cycles per second (MHz) or billions of cycles per second (GHz). The number of pulses generated by the clock within a specific unit of time is known as the clock speed. The microprocessor utilizes this clock speed to regulate the sequencing and execution of various operations in the computer. In simpler terms, the System Clock sets the overall rhythm and timing for the microprocessor’s activities, ensuring that instructions and data are processed at the desired speed.
d) Differentiate between CISC and RISC processors.
Basis
CISC Processors
RISC Processors
1. Instruction Set
Complex Instruction Set Computer
Reduced Instruction Set Computer
2. Number of Instructions
Large set of instructions of variable sizes
Small set of simple instructions of uniform length
3. Complexity
Includes many special-purpose circuits
Less complex and less expensive to produce
4. Memory Access
Instructions interface with memory in multiple mechanisms with complex addressing modes
Instructions interface with about 32-36 registers
5. Program Size
Program size is reduced, requiring fewer memory cycles
Program size is larger, requiring more memory cycles
6. Registers
Fewer general-purpose registers (8-12)
More general-purpose registers
7. Program Execution
Faster execution of programs due to fewer memory cycles
Program execution may require combining or repeating operations
8. Examples
Intel Pentium
SPARC, POWER PC
e) Why do we use secondary storage? Name any two secondary storage devices.
We use secondary storage for two main reasons:
1.
Permanence: Secondary storage devices are used to store data and programs permanently. Unlike primary memory (RAM), which is volatile and loses all information when the electricity is turned off, secondary storage retains data even when power is removed. It provides a non-volatile storage solution for long-term data storage.
2.
Portability: Secondary storage allows us to transport data from one computer to another. Devices such as CDs, DVDs, pen drives, and external hard disks are portable and can be easily carried and connected to different computers, making data transfer and sharing convenient.
Two examples of secondary storage devices are:
1.
Hard Disk: It is an internal storage medium consisting of one or more circular disks called platters. Each platter has a magnetic coating where data is recorded. Hard disks provide large storage capacities and are commonly used for long-term data storage in computers.
2.
Pen Drive/Flash Drive: Also known as thumb drives or USB flash drives, pen drives are portable storage devices that use flash memory. They connect to computers via a USB connector and provide a compact and convenient way to store and transfer data between devices.
f) How is Computer’s internal memory important?
Computer’s internal memory is extremely important for the functioning and performance of a computer system. Here are a few key reasons why computer’s internal memory is important:
1.
Storage of Instructions and Data: The internal memory, specifically RAM (Random Access Memory), is responsible for storing instructions and data that are actively used by the computer’s processor. When we run programs or perform tasks on a computer, the instructions and data are loaded into the RAM for quick access and processing. Without sufficient RAM, the computer may struggle to handle multiple tasks or run complex programs smoothly.
2.
Fast Access and Retrieval: The internal memory provides fast access and retrieval of data and instructions compared to other storage devices like hard disks or solid-state drives. Since the internal memory is located directly on the motherboard and connected to the processor, it allows for quick data transfer and retrieval, enabling efficient execution of instructions and faster overall performance.
3.
Temporary Storage: Internal memory serves as a temporary storage space for data and instructions that are actively being used by the computer. It allows for quick read and write operations, facilitating the smooth execution of programs. The temporary nature of the internal memory also means that its contents are volatile and are lost when the power is switched off, which allows for flexibility and dynamic allocation of resources.
4.
Interaction with Other Components: The internal memory plays a crucial role in facilitating communication and interaction between various components of the computer system. It acts as a bridge between the processor, input/output devices, and other hardware components, enabling data transfer and synchronization. This seamless interaction ensures the proper functioning of the computer system as a whole.
In summary, the computer’s internal memory is essential for storing and accessing instructions and data, enabling fast processing, facilitating communication between components, and overall enhancing the performance and efficiency of the computer system.
g) Why is it more appropriate to call RAM as Read-Write memory?
RAM (Random Access Memory) is more appropriate to be called a Read-Write memory because it allows both reading from and writing to its memory cells.
In the context of computer memory, “reading” refers to accessing and retrieving data or instructions stored in the memory, while “writing” refers to the process of storing or modifying data or instructions in the memory. RAM provides the capability to perform both of these operations.
When we input instructions or data into a computer, they are temporarily stored in the RAM. The CPU (Central Processing Unit) can read these instructions and data from RAM to execute programs or perform operations. Additionally, the CPU can write new data or modify existing data in RAM during the execution of programs.
Unlike Read-Only Memory (ROM), where the contents are pre-programmed by the manufacturer and cannot be changed or modified, RAM allows for dynamic and flexible storage. The information stored in RAM is volatile, meaning it is lost when the power is switched off or interrupted. However, while the power is on, RAM provides a fast and efficient medium for storing and retrieving data, making it suitable for the temporary storage needs of a computer system.
In summary, RAM is called a Read-Write memory because it allows for both reading and writing operations, enabling the storage and retrieval of data and instructions during the operation of a computer.
h) What is the purpose of Cache memory?
The purpose of cache memory is to store frequently accessed data and instructions in a high-speed memory to improve the overall performance of a computer system.
In a computer system, the CPU (Central Processing Unit) processes instructions and data. However, the processing speed of the CPU is much faster than the access time of the main memory. This means that the CPU often has to wait for data to be retrieved from the slower main memory, which can cause delays and decrease overall system performance.
To overcome this performance gap, cache memory is used. Cache memory is a small, but fast memory that is located between the CPU and the main memory. Its purpose is to store copies of frequently accessed data and instructions so that they can be quickly accessed by the CPU.
When the CPU needs to access data or instructions, it first checks the cache memory. If the requested data or instructions are found in the cache (referred to as a “cache hit”), they are immediately transferred to the CPU, avoiding the need to access the slower main memory. This significantly reduces the waiting time for the CPU and improves system performance.
However, if the requested data or instructions are not found in the cache (referred to as a “cache miss”), the CPU has to access the main memory to retrieve the required information.
Cache memory works efficiently because most programs exhibit temporal locality, meaning they tend to access the same data and instructions repeatedly. By storing frequently used data in the cache, the system can achieve faster access times for these commonly accessed elements.
There are typically two levels of cache memory:
1.
L1 cache: This is a small and fast cache memory built directly inside the CPU. It provides the closest and fastest access to the CPU.
2.
L2 cache: This cache memory is larger but slower than L1 cache and is typically located on the motherboard. It serves as a secondary cache and provides additional storage capacity for frequently accessed data and instructions.
In summary, the purpose of cache memory is to reduce the CPU’s waiting time by storing frequently accessed data and instructions in a high-speed memory, enabling faster access and improving overall system performance.
j) Distinguish between the following pairs:
a.
Primary memory and Secondary memory
b.
RAM and ROM
c.
Bluetooth and Infrared port
The following is the differentiation between the primary memory and secondary memory.
Basis
Primary Memory
Secondary Memory
1. Accessibility
Directly accessible by the CPU
Indirectly accessible by the CPU
2. Storage Purpose
Stores data and instructions currently being processed
Stores data and programs for long-term storage
3. Volatility
Volatile – Loses contents when power is switched off
Non-volatile – Retains contents even when power is switched off
4. Data Access Speed
Faster access speed compared to secondary memory
Slower access speed compared to primary memory
5. Storage Capacity
Smaller storage capacity compared to secondary memory
Larger storage capacity compared to primary memory
6. Price
Comparatively expensive
Comparatively inexpensive
7. Examples
RAM (Random Access Memory), ROM (Read Only Memory)
Hard disks, floppy disks, CDs, DVDs, pen drives, SSDs, magnetic tapes, Blu-ray disks
In summary, primary memory is the main memory of a computer system that is directly accessed by the CPU and is volatile, while secondary memory is external storage used for long-term storage and is non-volatile.
The following is the differentiation between RAM and ROM
Basis
RAM (Random Access Memory)
ROM (Read-Only Memory)
1. Accessibility
Data can be accessed from any desired location randomly
Data can only be read and cannot be modified or written
2. Read/Write
Data can be both read from and written to
Data can only be read and cannot be modified or written
3. Volatility
Volatile – Loses its contents when power is switched off
Non-volatile – Retains its contents even when power is switched off
4. Contents
Stores instructions and data being processed
Contains pre-written data or instructions that are permanent
5. Altering Data
Data can be modified and altered
Data is fixed and cannot be changed or modified
6. Usage
Used for storing temporary data and program instructions
Used for storing essential instructions and data that do not require alteration
7. Examples
RAM chips in computers
BIOS ROM, firmware, microcode
The following is the distinguishion between the Bluetooth and Infrared ports:
Basis
Bluetooth Port
Infrared Port
1. Transmission Technology
Uses radio waves to transmit data
Uses infrared waves to transmit data
2. Range
Short-range communication, typically up to 100 meters
Short-range communication, typically up to 5 meters
3. Line of Sight
Does not require a direct line of sight between devices
Requires a direct line of sight between devices
4. Interference
Less prone to interference from obstacles and walls
More prone to interference from obstacles and sunlight
5. Data Transfer Rate
Higher data transfer rate, about 2 megabits per second
Slower data transfer rate compared to Bluetooth
6. Device Compatibility
Requires Bluetooth-enabled devices to establish a connection
Requires devices with infrared ports to establish a connection
7. Usage
Commonly used for wireless communication between devices
Commonly used for TV remote controls and some older devices
