System Clock
In general, the clock refers to a microchip that regulates the timing and speed of all computer functions. In the chip is a crystal that vibrates at a specific frequency when electricity is applied. The shortest time any computer is capable of performing is one clock, or one vibration of the clock chip. The speed of a computer processor is measured in clock speed, for example, 1 MHz is one million cycles, or vibrations, a second. 2 GHz is two billion cycles, or vibrations, a second.
A system clock or system timer is a continuous pulse that helps the computer clock keep the correct time. It keeps count of the number of seconds elapsed since the epoch, and uses that data to calculate the current date and time.
Some of the characteristics of the system clock are as follows:
- The system clock is used to produce a specific pulse at a fixed rate of time.
- The machine cycle of a system can be completed in a single or multiple clock pulses.
- A single program instruction could be multiple instructions for the Cpu.
- Any central processing unit has a predefined set of instructions also known as the instruction set. These are the instructions that it can process and understand.
- The clock speeds are nowadays measures in Ghz. 1ghz = 1000 mhz
Address Bus
An address bus is a computer bus architecture. It is used to transfer data between devices. The devices are identified by the hardware address of the physical memory (the physical address). The address is stored in the form of binary numbers to enable the data bus to access memory storage.
A collection of wires connecting the CPU with main memory that is used to identify particular locations (addresses) in main memory. The width of the address bus (that is, the number of wires) determines how many unique memory locations can be addressed. Modern personal computers and Macintoshes have as many as 36 address lines. That lets them, which enables them theoretically to access 64 gigabytes of main memory. However, the actual amount of memory that can be accessed is usually much less than this theoretical limit due to chipset and motherboard limitations.
An address bus is part of the system bus architecture, which was developed to decrease costs and enhance modular integration. However, most modern computers use a variety of individual buses for specific tasks.
An individual computer contains a system bus, which connects the major components of a computer system and has three main elements, of which the address bus is one, along with the data bus and control bus.
An address bus is measured by the amount of memory a system can retrieve. A system with a 32-bit address bus can address 4 gigabytes of memory space. Newer computers using a 64-bit address bus with a supporting operating system can address 16 exbibytes of memory locations, which is virtually unlimited.
Data Bus
A data bus is a system within a computer or device, consisting of a connector or set of wires, that provides transportation for data. Different kinds of data buses have evolved along with personal computers and other pieces of hardware.
In general, a data bus is broadly defined. The first standard for data bus was 32-bit, whereas newer data bus systems can handle much greater amounts of data. A data bus can transfer data to and from the memory of a computer, or into or out of the central processing unit (CPU) that acts as the device’s “engine.” A data bus can also transfer information between two computers.
The use of the term “data bus” in IT is somewhat similar to the use of the term “electric busbar” in electronics. The electronic busbar provides a means to transfer the current in somewhat the same way that the data bus provides a way to transfer data. In today’s complicated computing systems, data is often in transit, running through various parts of the computer’s motherboard and peripheral structures. With new network designs, the data is also flowing between many different pieces of hardware and a broader cabled or virtual system. Data buses are fundamental tools for helping facilitate all of the data transfer that allows so much on-demand data transmission in consumer and other systems.
A data bus is a system within a computer or device, consisting of a connector or set of wires, that provides transportation for data. A data bus is also called a processor bus, front side bus, frontside bus or backside bus—is a group of electrical wires used to send information (data) between two or more components. A databus is a data-centric software framework for distributing and managing real-time data in the IIoT. It allows applications and devices to work together as one, integrated system. The databus simplifies application and integration logic with a powerful data-centric paradigm. Instead of exchanging messages, software components communicate via shared data objects. Applications directly read and write the value of these objects, which are cached in each participant. A data bus has many different defining characteristics, but one of the most important is its width. The width of a data bus refers to the number of bits (electrical wires) that make up the bus. Common data bus widths include 1-, 4-, 8-, 16-, 32-, and 64-bit.
Key characteristics of a databus are:
- The participants/applications directly interface with the data
- The infrastructure understands, and can therefore selectively filter the data
- The infrastructure imposes rules and guarantees of Quality of Service (QoS) parameters such as rate, reliability and security of data flow
Cache Memory
Cache memory is a chip-based computer component that makes retrieving data from the computer’s memory more efficient. It acts as a temporary storage area that the computer’s processor can retrieve data from easily. This temporary storage area, known as a cache, is more readily available to the processor than the computer’s main memory source, typically some form of DRAM.
Cache memory is sometimes called CPU (central processing unit) memory because it is typically integrated directly into the CPU chip or placed on a separate chip that has a separate bus interconnect with the CPU. Therefore, it is more accessible to the processor, and able to increase efficiency, because it’s physically close to the processor.
In order to be close to the processor, cache memory needs to be much smaller than main memory. Consequently, it has less storage space. It is also more expensive than main memory, as it is a more complex chip that yields higher performance.
What it sacrifices in size and price, it makes up for in speed. Cache memory operates between 10 to 100 times faster than RAM, requiring only a few nanoseconds to respond to a CPU request.
The name of the actual hardware that is used for cache memory is high-speed static random access memory (SRAM). The name of the hardware that is used in a computer’s main memory is dynamic random access memory (DRAM).
Cache memory is not to be confused with the broader term cache. Caches are temporary stores of data that can exist in both hardware and software. Cache memory refers to the specific hardware component that allows computers to create caches at various levels of the network.
Types of cache memory
Cache memory is fast and expensive. Traditionally, it is categorized as “levels” that describe its closeness and accessibility to the microprocessor. There are three general cache levels:
L1 cache, or primary cache, is extremely fast but relatively small, and is usually embedded in the processor chip as CPU cache.
L2 cache, or secondary cache, is often more capacious than L1. L2 cache may be embedded on the CPU, or it can be on a separate chip or coprocessor and have a high-speed alternative system bus connecting the cache and CPU. That way it doesn’t get slowed by traffic on the main system bus.
Level 3 (L3) cache is specialized memory developed to improve the performance of L1 and L2. L1 or L2 can be significantly faster than L3, though L3 is usually double the speed of DRAM. With multicore processors, each core can have dedicated L1 and L2 cache, but they can share an L3 cache. If an L3 cache references an instruction, it is usually elevated to a higher level of cache.
In the past, L1, L2 and L3 caches have been created using combined processor and motherboard components. Recently, the trend has been toward consolidating all three levels of memory caching on the CPU itself. That’s why the primary means for increasing cache size has begun to shift from the acquisition of a specific motherboard with different chipsets and bus architectures to buying a CPU with the right amount of integrated L1, L2 and L3 cache.
Contrary to popular belief, implementing flash or more dynamic RAM (DRAM) on a system won’t increase cache memory. This can be confusing since the terms memory caching (hard disk buffering) and cache memory are often used interchangeably. Memory caching, using DRAM or flash to buffer disk reads, is meant to improve storage I/O by caching data that is frequently referenced in a buffer ahead of slower magnetic disk or tape. Cache memory, on the other hand, provides read buffering for the CPU.
Processing Speed
Processing speed is one of the main elements of the cognitive process, which is why it is one of the most important skills in learning, academic performance, intellectual development, reasoning, and experience.
Processing speed is a cognitive ability that could be defined as the time it takes a person to do a mental task. It is related to the speed in which a person can understand and react to the information they receive, whether it be visual (letters and numbers), auditory (language), or movement. In other words, processing speed is the time between receiving and responding to a stimulus.
Slow or poor processing speed is not related to intelligence, meaning that one does not necessarily predict the other. Slow processing speed means that some determined tasks will be more difficult than others, like reading, doing math, listening and taking notes, or holding conversations. It may also interfere with executive functions, as a person with slow processing speed will have a harder time planning, setting goals, making decisions, starting tasks, paying attention, etc.
Processing speed implies a greater ability to easily do simple or previously-learned tasks. This refers to the ability to automatically process information, which means processing information quickly and without doing it consciously. The higher the processing speed, the more efficient you are able to think and learn.
Processing speed is the time that lapses from when you receive information until you understand it and start to respond.
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