Computer Architecture

Computer Architecture

Von Neumann architecture

The Von Neumann architecture as is famously known draws its origin in the year 1945 when the mathematician and computer scientist, Von Neumann and other scholars developed a proposal that cr5eated the first ever EDVAC. Von Neumann architecture generally is one of the original developmental designs of digital computing that characterized the computer into four fundamental partitions. The partitions or subdivisions are for instance, the processing section or unit that is designed in terms of arithmetic capacity unit as well as registers responsible for processing. The second unit is that of the control section which is very fundamental and it deals with instruction register and program counter. However, over the years, the meaning and understanding of the concept Von Neumann architecture has been redefined purposely due to the limitations it has in comparison to the latest generation computers in what is referred to as “Von Neumann Bottleneck”. The architecture came to be known as the “stored program computing” in which two simultaneous functions of instruction command and data storage does not occur at one instance owing to the fact that they shared a the same bus (Goldstine and von Neumann, 1955).

The importance of Von Neumann architecture stems from the fact that it is often used as a tool of comparison. It is hard to offer any credible discussion of computer architecture without throwing a spanner at the work done by Neumann due to the fact that almost every electronic computer ever built draws its background on the work done by Neumann. That is, Von Neumann architecture is seen as the foundation stone for the latest trends of electronic computing which are developed as an improvement of the work done by Neumann (Goldstine and von Neumann, 1955).

System Bus

The concept of system bus stems from the fact that computer’s central processing unit which is the nerve centre of the computer has to transmit or send data information to all the internal components or devices within the computer as well as to any other external devices. Internally, bottom of the motherboard contains a series of electronic pathways embedded as wires that connect all the important components that enable the computer to transmit information. It is these series of wires that make electronic pathways that are referred to as a system bus. A system bus is therefore a single computer bus that connects various components of the computer and which allows for effective transmission of data information across those components. A system bus essentially carries out three integrated functions of data bus or in other words information transmission, address bus which determines the specific direction the processed information should taken to, and lastly the control bus that determines the modes of operation on the transmitted data (Linda and Julia, 2010).

System bus was created as an improvement of the famous Von Neumann architecture majorly to serve fundamental roles of cost saving as well as modularity. It is important to note that during the periods of 1950s and 1960s, manufactured computers generally took an ad-hoc fashion whereby computer components such as CPU, memory, input/output devices were each placed on different cabinets or manufactured as parts and were only connected by cables. From this perspective therefore, the costs involved were massive as one had to buy different parts which further required more space for installation. Therefore, it is clearly evident that integration of computer’s different components serves important functions of both improved modularity and cost saving since it incorporates a rather disintegrated components into one single system bus that saves on both material used and installation space (Goldstine and von Neumann, 1955).

Boolean operators in computer-based calculations

As a way of introduction, Boolean operations can be described as computer commands used adopted by the system search engines to integrate both ordinary words and phrases in a manner that the computer can understand and process meaningfully. That is, without them, the computer will not be able to comprehend data in-put which subsequently will lead to no credible results at all. Boolean operations vary from the normal algebraic operations in three fundamental directions of values, laws and operations. For instance, as opposed to the usual algebraic values such as 1, 2, 3 e.t.c , Boolean operations takes cognizance of only two values of 0 and 1 which are defined as algebraic truth values. Manipulation of the two absolute values or their subsets involves the use of three mathematical connotations of conjunction, disjunction and negation which are represented as ∧, ∨ and ¬.

To understand the basic functioning of Boolean algebraic operations for computer processing, it is important to understand the notation of its values. This is particularly important because as opposed to the usual algebraic numbers stretching from 0 through 9, here we conceptualize only two values, that is, 0 and 1 popularly known as false and truth values respectively (Siewiorek, 1985).

Boolean operations share a lot in terms of digit manipulation to those of the ordinary algebra. For instance, ordinary algebraic multiplication, XY, addition, X+Y, and negation, -X all apply in the Boolean operations and are represented by conjunction x∧y, disjunction x∨y and negation or complement ¬x. The use of conjunction on truth values 0 and 1takes the same form to those of ordinary operations. Therefore, x∧y implemented on 0 and 1 yields 0, that is, 0*1=0. At the same time, when the values of X and Y are 1, the result of conjunction becomes 1. Operations of disjunction also take the same pattern as those of ordinary with only one exception. In disjunction, 1∨1 is not 2, but takes the value1 (Siewiorek, 1985). The same format of ordinary algebra also works for negation operations with little variation. The general rules for Boolean operations can be represented mathematically as:

x∧y = xy

x∨y = x + y − xy

¬x = 1 – x

Types of memory and storage

Computer memory and storage related to the devices or computer components that are functionally installed into a computer for the sole purpose of storing information and application either on a permanent or temporary basis. The developments in information technology have led to the invention of various types of computer memories with each having different attributes (Siewiorek et.al, 1982).

The first in the line of computer memories is the Read only Memory (ROM) whose major attribute is that it stays on even the computer is shut down or on. Another fundamental character of ROM is the fact that the contents of data stored here cannot be modified or edited. In other words, the contents of materials stored in ROM form an integrated component that must be present in order for the computer to be able to function (Linda and Julia, 2010).

Another type of computer memory is the Random Access Memory (RAM). RAM is one of the important computer storage devices and it purposely stores data or stacks away data on a temporary basis with the full intention that such data can be promptly and effectively accessed by the processor. Importantly, it is crucial to note that data stored in RAM originates from the computer hard disc and relates to those data concerned with the operating system or certain software applications that are essential for efficient functioning of the computer. A distinctive feature of RAM and which differentiates it from ROM is that when the computer is switched off, the entire stored are lost but can be retrieved when the system is switched on (Linda and Julia, 2010).

The kind of computer storage is the so called Cache which by design is more of a RAM with the exception that the computer system uses it in a more responsive manner than the ordinary RAM. When the central processing unit is looking for information in the system, it first looks into the cache before resorting to look in the general central memory storage. Computer hard drives are also used as important computer storage devices and they are installed in the CPU. The size of hard disk drives varies and the user is obliged to choose which suits his or her needs.  Another common storage device is the flash memory which is designed to aid in portability of stored data from one location to the next. Importantly, the stored in it can be manipulated by being changed, edited, erased and re-programmed according to the requirements of the user (Linda and Julia, 2010).