• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Cisc v risc. To begin this assignment , I will outline the definition of cisc and risc . Cisc stands for complex instruction set computing and Risc stands for reduced instruction set computing . these two concepts are both types of instruction sets used

Extracts from this document...

Introduction

Cisc v Risc

Introduction:

To begin this assignment , I will outline the definition of cisc and risc . Cisc stands for complex instruction set computing and Risc stands for reduced instruction set computing . these two concepts are both types of instruction sets used in computer architecture for processors and microprocessors . computer architecture is a way of examining the structure of a computer, we mainly focus on the how the cpu performs internally and how it accesses addresses in computer memory. The objective of the microprocessor is to advance the performance of the machine. Performance can be defined as the amount of work a processor can do in a set time .

image00.png

In order to improve the computers performance we would have to increase the speed of how we process these instructions or else make these instructions more complex so they will perform more work, but we can’t have both. Speeding up the instructions (cisc) means changing the clock speed of the computer , while making the instructions more complex (risc) means we will require more power to process them. An real life analogy of this instruction set concept would be to take a bike for example , if we are in a low gear we can pedal really fast to get where we are going but in a high gear we can go the same distance but we require more power to push the pedals. In the following sections I will try and explain the two concepts of Cisc and Risc  and where they originated from and the advantages and disadvantages .

image01.png

History:

The cpu ( central processing unit ) can be sometimes referred to as the brain of the computer as it does all the work for the programmes and applications .

...read more.

Middle

Decode : decodes the instruction and looks for operands.Execute : performs the instruction e.g( addition , substraction)Memory : accesses the memory and writes data or retrieves data from it.Write back : records the calculated value in a register.

As mentioned above the goal of pipelining is to perform each step paraellel , so as one instruction is being retrived ( fetch ) the previous one is being read ( decode ) while the previous one to that is being performed ( executed ) and so on .. there can be many steps in pipelining but in general the main ones are outline above , to understand this pipeling process more see diagram below,

image03.png

From the 1960scisc microprocessors became prevalent , and each successive processor having more complicated hardware. Some examples of cisc architecture in processers are the ibm360, intel 80386 , and the Motorola 68030. Most of intels chips from the 8008 microprocessor to the Pentium 4 are all based around the cisc approach.

Ibm 360 :

Back in 1960 most computers would have been designed independently or machines were custom modified for a customer . in 1964 ibm changed all this when they brought out the ibm 360 computers. The computers could range from the model 20 ( 24 kb of memory ) to the model 91 super computer which was bult for missile defence in north America . the computers had different operating systemsbut all had the same instruction set. The low end machines didn’t or could support operating systems  and a program was loaded from binary punched cards at start up. The higher end machines called 0s/360 established 32 bits as the standard for computers. See below ibm 360 computer.

image04.jpg

The advantages of cisc:

When cisc instruction sets were first developed , cisc machines used technologies available to optimize computer performance . micro programming was a assembly language that was reatively easy to introduce and was at less cost than hardwiring a control unit.

...read more.

Conclusion

.

Summary :

in todays computer world the vast majority of risc cpus are 32 –bit . the risc design offers  power in even small sizes.Today, the Intel x86 is arguable the only chip which retains CISC architecture. In some cases we can see that both architectures are becoming more and more alike . most of todays risc chips support as many instructions as previous cisc chips and also todays cisc chips can be seen using the same techniques which would have been associated with the risc chip . even intel today which is the main player for the cisc architecture can be seen using some of the risc technology approaches .

References:

  • Chen.C ,Novick .G, Shinamo.K

2000

Risc architecture,

http://www-cs-faculty.stanford.edu/~eroberts/courses/soco/projects/2000-01/risc/about/index.html

 last accessed = 2/11/10

  • Author :unknown

The cpu shack,

2005

http://www.cpushack.com/CPU/cpuAppendA.html

last accessed = 2/11/10

  • Gao.y, Tang.s ,Ding.z

Comparison between cisc and risc

http://www.scribd.com/doc/1902877/risc-cisc

last accessed = 30/10/10

  • j.jeff,

Processor ,

2004,

http://en.kioskea.net/contents/pc/processeur.php3

last accessed = 29/10/10

  • author : unknown,

risc tutorial,

2009

http://www.laynetworks.com/RISC.htm

last accessed = 3/11/10

  • Mccaldin. D

What is the risc in computer architecture ?

2009

http://knol.google.com/k/what-is-the-risc-in-computer-architecture#

last accessed = 3/11/10

  • Ibm corporation

Mainframes introduction 2

Year= unknown

http://www-03.ibm.com/ibm/history/exhibits/mainframe/mainframe_intro2.htmlr

last accessed = 25/10/10

Images:

  1. Performance equation

http://www-cs-faculty.stanford.edu/~eroberts/courses/soco/projects/2000-01/risc/risccisc/

  1. Cisc v risc comparison

http://www.appuntidigitali.it/7671/motorola-68060-una-cpu-superscalare-risc-per-lultimo-componente-della-famiglia/

  1. Mos transistor

http://en.kioskea.net/contents/pc/processeur.php3

  1. Pipelining diagram

http://en.kioskea.net/contents/pc/processeur.php3

  1. Ibm360/91

http://www.columbia.edu/acis/history/360-91-panel.jpg

  1. Storage scheme for a computer

http://www-cs-faculty.stanford.edu/~eroberts/courses/soco/projects/2000-01/risc/risccisc/

...read more.

This student written piece of work is one of many that can be found in our University Degree Computer Science section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Here's what a teacher thought of this essay


A lot of copied and misunderstood material and far too detailed at this level. Also lots of spelling, grammar and some factual errors. However the second half of the piece is generally accurate and informative

Marked by teacher Ivor Borkin 30/11/2013

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related University Degree Computer Science essays

  1. Marked by a teacher

    UK Copyright and File Sharing

    5 star(s)

    Napster operated a system where the user's computer program connects to a central host (i.e. the Napster servers). The user could choose what song they wanted to download by searching for it in the application. The Napster server would scan through its entire index of all songs under the search

  2. Design a web based online Appointment System for vehicle service centres in town to ...

    Normally an appointment is made over the phone or direct contact. It is being handled by a staff or an appointed person at the centre. So I have decided to design a system which enables the customers to make appointments online with Service Centres.

  1. Traffic Light Simulation and Machine Code Program.

    CALL 60 ; CALLS SUBROUTINE 60 (DELAY SUBROUTINE) ; RED - RED MOV AL,90 ; Copy 10100000 into the AL register. OUT 01 ; Send AL to Port One (The traffic lights). MOV BL,01 ; SENDS VALUE 01 to BL. CALL 60 ; CALLS SUBROUTINE 60 (DELAY SUBROUTINE)

  2. State two advantages and two disadvantages of a layered operating system.

    A context switch occurs when a thread releases the processor, and whereby the task/process of the front of the ready queue becomes the new active task. The execution context of the previous thread has to be saved so that the thread can be used later.

  1. NETWORK DESIGN PROPOSAL

    This proposal describes a WAN that integrates and updates these LANs to support productive collaboration across the system. 3. Versatile Information Processing: The network will enable users to retrieve, process, and store ASCII and non-ASCII text, still graphics, audio, and video from any connected computer.

  2. There are different types of voting systems used around the world in this assignment ...

    Proportional Representation Proportional Representation is an electoral system which tends to make elections result in groups of votes being represented in proportional fractions by the outcome of votes otherwise representation of all parties in proportion to their popular vote. The PR system is highly favoured rather then the FPTP system.

  1. This report will discuss the benefits and constraints of network systems and topologies.

    Illustration: Bus Topology Diagram C:\Users\AISOSA\Documents\Bus Topology.JPG htts//wwwlifewire.com/computer-network-topology-817884 *Ring Topology This a topology network where every device has just two neighbours for communication reasons. All communications go through a ring in the same direction (either "clockwise" or "counter clockwise") in circles.

  2. Airline Reservation System

    The site would use a Database to hold this information as well as the latest pricing and availability information for the airlines. 1. Problem statement: The existing airline reservation system has many shortcomings associated with it. In the existing system airlines used to set flight reservation levels higher than seating

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work