Computer System Architecture Basics PDF

IT1910 Architecture Basics COMPUTER SYSTEM A computer is a device that can compute for the desired information through entering information. A system, on the other hand, can be defined as many e...

IT1910 Architecture Basics COMPUTER SYSTEM A computer is a device that can compute for the desired information through entering information. A system, on the other hand, can be defined as many elements working as one. It is a working procedure or methods to which a process is formed. A computer system, therefore, is a system that comprises elements that process raw data and instruction. Elements of a Computer System  Data – It is the fundamental representation of facts and observations. It is processed by a computer system to provide information, which is the very reason for the computer’s existence. It can also take on a number of different forms: numbers, text, images, and sounds. However, it’s all numbers on the computer.  Software – It consists of system and application programs that define the instructions executed by the hardware. It has an application programming interface (API) that acts as an interface for application programs and utilities to access the internal services provided by the operating system. It also has a kernel that contains the most important operating system processing functions. Here are some examples of software: System software – Operating system (Windows 10) Application software – Web browser (Google Chrome)  Hardware – This includes devices that process data by executing instructions, storing data, and moving data and information between various Input/Output (I/O) devices, making the system and information accessible to users. Listed below are the basic hardware components that a computer has: Microprocessor – It is where the computer processes all data and instructions (or commands that a computer must do). Primary Storage – It is mostly used as temporary storage for processed data and running applications. Most of them are volatile. Some of the examples are random access memory (RAM) and cache memory. Secondary Storage – It is used to store files, applications, and operating system. o HDD (Hard Disk Drive) – It is a type of a non-volatile storage media that stores data on spinning magnetic disks rotating at a high-speed. o Flash Drive – It is a type of non-volatile storage media that stores data in a single flash memory. It is known for its portability. o SSD (Solid State Drive) – It is a type of a non-volatile storage media that stores data on a series of solid-state flash memory. It is known for its amazingly fast reading and writing data. Input devices o Keyboard – It is one of the primary input devices composed of buttons with alphanumeric characters. It also performs other functions. o Mouse – It is a handheld input device that is capable of controlling and maneuvering graphical user interface (GUI) with the use of a cursor on display. 01 Handout 1 *Property of STI  [email protected] Page 1 of 4  IT1910 Output devices o Monitor – It is capable of displaying the GUI of a computer. o Printer – It is capable of representing data on paper.  Communication – It consists of hardware and software that transport programs and data between interconnected computer systems. A communication channel provides the connection between computers. Some of the data media channels are copper, fiber-optic, and wireless (infrared [IR], radio frequency [RF], Wi-Fi, and Bluetooth). ARCHITECTURE Architecture in computer systems is the design of computer components in hardware being used, in the flow of data input-process-storage-output within the system, in algorithms being implemented, and more. The design can be distinguished into two (2): by form and by function. Design by Form: Classification of Computers Design by form refers to the structure and size of a system. From the structure of the system, computer systems can be classified by form to distinguish form factor. Microcomputers are usually small, low cost, and intended for one (1) user or one (1) device. These are used for a large variety of applications, from network access to business, educational, and entertainment applications and even games. (e.g., PC, PDA, gadgets, and console) Minicomputers are generally used in a multiuser environment. These servers act as a platform for a specific application, such as a print server that manages all printers and handles all print tasks or a mail server that manages all the organization’s mail. (e.g., single rack server [print, Web, file]) Mainframes are large organizational computer systems that act as the main computational infrastructure. These are usually very powerful and support many concurrent users.These systems host an organization’s databases and provide applications to support all business processes. (e.g., server farms [dsata centers]) Design by Function: Computer Operations Design by function pertains to the specific instruction or process that a computer system must have to meet criteria and application. These are the simplest functions of a computer: Input/Output pertains to the placing of data in or out of the computer system. Basic arithmetic and logical calculations pertains to mathematic calculations and comparison. Data transformation or translation pertains to the data that changes from one form to another due to instruction or need. Data sorting pertains to arrangement of data by a list or specific criterion or criteria. Searching for data matches pertains to the comparison of data to suffice condition. Data storage and retrieval pertains to getting and/or placing data in a non-volatile storage. Data movement pertains to the placement of data from one memory location to the other. Design by Function: Moore’s Law In addition to function, Moore’s Law can be included as a design by function due to the rapid influx of technology in today’s standards. From the semiconductor industry perspective, this law represents designing for rapid change of hardware. Thus, new architecture and emerging technology arise and is much better than 01 Handout 1 *Property of STI  [email protected] Page 2 of 4  IT1910 the first one. It also states that integrated circuit resources double every 18–24 months. This law relies on “Transistor count” as a basis for the advancement of integrated circuit. Figure 1. Transistors versus years according to Moore’s Law Architecture Complexity As technology arises, computers become more advance to the point of designing complex computer systems for a specific purpose. Thus, this results in the complexity of computer design. Through the complexity of computer architecture, the design and understanding of computer systems become harder. Solutions to Architecture Complexity These are the different solutions to solve this architecture complexity challenges:  Abstraction – It is used to characterize a certain object at different levels of representation offering models. Basically, it is an ideal model put into a representation. Figure 2. An example of abstraction – Input-process-output model.  Computer Hierarchy – It is a structure that has a predetermined ordering from high to low. It refers to systems that are organized in the shape of a pyramid, with each row of objects linked to objects directly beneath it. 01 Handout 1 *Property of STI  [email protected] Page 3 of 4  IT1910 Figure 3. An example of setting of hierarchy in computer terms (Memory hierarchy)  Decomposition – It is a process of splitting the system in smaller chunks; people can work better by working on smaller separate tasks. Once the system is decomposed, it does the following: Work on each chunk in different times (prioritizing important chunks) Give each chunk to a different person/team (work can be done in parallel). References: Berekovic, M., Buchty, R., Hamann, H., Koch, D., & Pionteck, T. (2018). Architecture of computing systems – ARCS 2018 proceedings. Switzerland: Springer Nature. Cargnegie Mellon Computer Architecture. (2015, January 24). Lecture 2. Fundamental concepts and ISA - Carnegie Mellon - Computer Architecture 2015 - Onur Mutlu [Video File]. Retrieved 2019, May 17 from https://www.youtube.com/watch?v=NpC39uS4K4o Elahi, A. (2018). Computer systems - Digital design, fundamentals of computer architecture and assembly language. Switzerland: Springer Nature. Englander, Irv. (2014). The architecture of computer hardware, systems software & networking (5th ed.). New Jersey: Wiley. Fisher, T. (2019). What is device manager? [Web log post]. Retrieved 2019, May 17 from https://www.lifewire.com/device-manager-2625860 Fisher, T. (2019). Task manager [Web log post]. Retrieved 2019, May 17 from: https://www.lifewire.com/task-manager- 2626025 Patterson, D. & Hennessy, J. (2017). Computer organization and design – The hardware/software interface. Massachusetts: Elsevier. Roser, M. & Ritchie, H. (2019). Technological progress. Retrieved 2019, May 17 from Our World in Data website: https://ourworldindata.org/technological-progress Space Challenges. (2015, March 23). What is systems architecture (PART 1) [Video File]. Retrieved 2019, May 17 from https://www.youtube.com/watch?v=gGI3n8qLDN0 Yadin, A. (2016). Computer systems architecture. Florida: CRC Press. 01 Handout 1 *Property of STI  [email protected] Page 4 of 4  IT1910 Data Formats Data, in computer terms, is a fact, figure, or information that is represented in a set of bits – ones and zeros. Wires and circuits bring forth these bits as electrical pulses in the computer system. These bits can be a file, information, or instruction. The user can edit, store, and delete data to meet his/her specific needs. Data in human form is entered to a computer using a keyboard, a mouse, or any other input device. From the human form, computers manipulate data to convert it to their own representation, which is in binaries of ones and zeros. General Considerations In order to follow the process of data, some considerations of each data flowing in the computer systems should be listed. 1. File Type – It is a name given to a specific kind of file. It may be either of the following examples: − Audio and video files − Image file − Compressed file − System-related and programming files − Disc and media files − Word processor and text files − Executable file − Presentation and spreadsheet files Terminologies for File Type a. File Name – It is a unique file identifier and may be named by a human or a computer. b. File Extension – It is a 1- to 4-letter character identifier for the specific file type. c. File Extension Icon – It is a common identifier for file extension. d. File Association – It is a program associated with the file extension. 2. File Format – It is a structure or layout of a computer file in terms of how data is contained and organized. The structure of a typical file may include a header, metadata, a saved content, and an end- of-file (EOF) marker. The data stored in the file depends on the purpose of the file format. 3. Metadata – It provides additional information about a certain item’s content. The other terms for metadata are descriptions, keywords, tags. (Example: JPEG – dimensions, date created, date accessed, color depth, etc.) 4. File Attributes – These are settings associated with computer files that grant or deny certain rights to how a user or the operating system can access that file. a. Read-only – It allows a file to be read, but nothing can be written to the file or changed. b. Archive – It tells Windows Backup to back up the file. c. System – It is a system file. d. Hidden – It is a file that cannot be seen when doing a regular directory. Classifications of Data As alphanumeric characters As a visual image (still and moving) As audio Internal computer data Data as Alphanumeric Characters Data are entered as characters, symbols, number digits, and punctuation. Specific input devices and methods are used to create these. (e.g., Keyboard, keypads, on-screen keys, magnetic card stripes, etc.) 02 Handout 1 *Property of STI  [email protected] Page 1 of 3  IT1910 Examples: 1. American Standard Code for Information Interchange (ASCII) was originally developed as a standard by the American National Standards Institute (ANSI). ANSI has also defined 8-bit extensions to the original ASCII codes that provide various symbols, line shapes, and accented foreign letters for the additional 128 entries. 2. Extended Binary Coded Decimal Interchange Code was developed by IBM. Its use is restricted mostly to IBM and IBM-compatible mainframe computers and terminals. 3. Unicode supports approximately a million characters, using a combination of 8-bit, 16-bit, and 32-bit words. It divides its character encodings into sixteen 16-bit code pages, called planes, which allows space for about a million characters. Data as Visual Data Images used within the computer fall into two (2) distinct categories: Bitmap objects are images (e. g., photographs and paintings) that are characterized using an image scanner, digital camera or mobile device, or video camera frame grabber. Graphical objects are images made up of graphical shapes (e. g., lines and curves) that can be defined geometrically. Examples: 1. Graphics Interchange Format (GIF) was first developed by CompuServe in 1987 as a proprietary format that would allow users to store and exchange online bitmap images in 256 colors on different computing platforms. Now, it is extensively used on the Web due to its animated frame-by-frame images. 2. Portable Network Graphics (PNG) is the best known compressed alternative to GIF. PNG can store up to 48 bits of color per pixel and can store a transparency percentage value and a correction factor for the color in a monitor or printer. 3. Joint Photographers Expert Group (JPEG) employs a compression algorithm to reduce the amount of data stored and transmitted. This algorithm reduces the image resolution under certain circumstances, particularly for sharp edges and lines, which makes JPEG more suitable for the representation of highly detailed photographs and paintings. Video images are a result of a sequence of bitmap image frames. The video format is determined by a codec or encoder/decoder algorithm referred to as a “container.” The container serves as a superstructure to encode, decode, hold, and stream video. It serves both video and audio and may support multiple codecs. Data as Audio Data Sound can be stored in digital form on storage media. Since the original sound wave is analog, conversion is needed to make it in digital form, where it is then sampled electronically at regular time intervals. Each time a sample is taken, it is measured by the ADC (Analog-to-Digital Converter) that converts the analog value to a digital (binary) equivalent (consists of sampling, quantization, and encoding). Sampling lays out of the analog signal in a graph. Quantization layers the discrete signal in the analog signal with less margin of error. Encoding converts discrete signals into highs (1) and lows (0), hence the binary equivalent of a time- bound discrete signal. 02 Handout 1 *Property of STI  [email protected] Page 2 of 3  IT1910 Internal Computer Data These are data types represented as interpretation from programming languages. Here are the factors to consider: The actual operations that the computer processor is capable of performing The data types that are supported by the programming language to create the application program. These are the simple data types: 1. Boolean – constant values (true/false) 2. Char – alphanumeric character code 3. Enumerated – user-defined data type 4. Integer – whole numbers (+ / -) 5. Real / Float – numbers with a decimal portion Data Compression Lossless algorithm compresses the data in such a way that the application of a matching inverse algorithm restores the compressed data exactly to its original form. Lossy algorithm operates on the assumption that the user can accept a certain amount of data degradation as a trade-off for the savings in a critical resource, such as storage requirements or data transmission time. References: A/D Converter and D/A Converter (n.d.). In ROHM Co., Ltd.’s website. Retrieved 2019, May 17 from https://www.rohm.com/electronics-basics/ad-da-converters/what-are-ad-da-converters Berekovic, M., Buchty, R., Hamann, H., Koch, D., & Pionteck, T. (2018). Architecture of computing systems – ARCS 2018 proceedings. Switzerland: Springer Nature. Christensson, P. (2011, March 15). File format definition. Retrieved from https://techterms.com/definition/file_format on May 17, 2019 Christensson, P. (2011, March 15). File type definition. Retrieved from https://techterms.com/definition/file_type on May 17, 2019 Computer Hope (2018). What are the most common file types and file extensions? [Web log post]. Retrieved 2019, May 17 from https://www.computerhope.com/issues/ch001789.htm Elahi, A. (2018). Computer systems - Digital design, fundamentals of computer architecture and assembly language. Switzerland: Springer Nature. Englander, I. (2014). The architecture of computer hardware, systems software & networking (5th ed.). New Jersey: Wiley. Ishida, R. (2010, August 12). Character encodings: Essential concepts. Retrieved from https://www.w3.org/International/articles/definitions-characters/ on May 17, 2019 Patterson, D. & Hennessy, J. (2017). Computer organization and design – The hardware/software interface. Massachusetts: Elsevier. [Techquickie]. (2018, September 28). Video file formats - MP4, MOV, MKV [Video File]. Retrieved from https://www.youtube.com/watch?v=hvgxn8v--8Q on May 17, 2019 WAVE PCM soundfile format (n.d.). In Soundfile: Basic Audio Programming in C++. Retrieved from http://soundfile.sapp.org/doc/WaveFormat/ on May 17, 2019 Yadin, A. (2016). Computer systems architecture. Florida: CRC Press. 02 Handout 1 *Property of STI  [email protected] Page 3 of 3