This document discusses the results of 5 tasks related to logic circuit design. Task 1 describes a half adder circuit that performs simple addition using logic gates. Task 2 details a full adder circuit that has three inputs and two outputs. Task 3 discusses designing a traffic light controller circuit using logic gates. Task 4 explains controlling two traffic lights using additional logic gates. Task 5 compares CISC and RISC processor designs, noting CISC uses complex instructions while RISC focuses on simplicity and speed.

1. Version 1
Individual Report – Project Two
Note: your report should be supported with appropriate references using Coventry University Harvard Reference Style.
Logic Circuit Design : Task 1
Results and Evidence:
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Adder circuit is a combinational digital circuit that is used for adding two numbers.
This is a half adder circuit, this circuit is capable of performing simple addition
using logic gates
The circuit was easy to make, but I had little problem getting use to the software.
@Coventry University
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2. Version 1
Logic Circuit Design : Task 2
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This is a full adder circuit and its different from a half adder because it has three
inputs and two outputs
The first two inputs are A and B and the third input is an input carry designated as
CIN. When full adder logic is designed we will be able to string eight of them
together to create a byte-wide adder and cascade the carry bit from one adder to the
next.
After getting use to the software I was able to create the full adder circuit without
any problem or difficulty.
@Coventry University
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3. Version 1
Logic Circuit Design : Task 3
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Designing a traffic light controller that uses logic gates that takes 2 Boolean inputs
A and B and outputs on three channels R, Y, G was not easy to build, due to my lack
of experience in electrical engineering. Had problems with selecting a logic gates so
I had to go read more about different logic gates and their functions.
After that I was able to build the circuit without any difficulty and I was also able to
make it work.
@Coventry University
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4. Logic Circuit Design : Task 4
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Designing this was really easy because I have been able to design a single traffic
light so all I had to do was add another traffic light to the one already built and also
add a NOR and XOR gate.
I was really impressed by the circuit diagram because I was able to control two
traffic light using input A and B.
@Coventry University
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5. Version 1
Logic Circuit Design : Task 5
CISC (complex instruction set computers) AND RISC (reduced instruction set computing) are
two types of ways to improve the design of central processing unit (CPU) of computers
which improve the speed and performance.
CISC (complex instruction set computers): this are computers designed with a full set of
computer instructions that were intended to provide needed capabilities in the most effective
way.
The main object of the CISC is to make task easy to complete and easy, this is why the CISC
uses complex and large instructions and also complex way of designing CPU because it
helps increase the performance of the CPU. The CISC uses hardware which is very capable
of executing and understanding series of operation to perform task. The CISC is built in with
an instruction which is specific to carry out complex task, this instruction is called MULT.
For example, when carrying out a multiplication of two numbers, the MULT instruction put
the two values that are being multiply together into separate registers and then multiplies the
operands in the execution unit, and then stores the product in the appropriate register.
The MULT instruction is the instruction that makes CISC complex because it operates
directly on the computer’s memory without the use of any instruction from a programmer
regarding loading or storing functions. The MULT instruction reconstructs a command in a
standard language.
RISC (reduced instruction set computing): is microprocessor that is designed to perform a
smaller number of types of computer instructions so that it can oprate at higher speed.
Unlike the CISC, RISC uses simple instructions that can be breakdown. The RISC helps
improve performance of a processor in a simple way without the use of complicated
instructions.
The RISC processor is much more cheaper than the CISC processor because the building
process requires less transistors which makes the chips for the RISC is cheaper to produce
compare to the CISC processor which has complicated instructions and requires bigger and
expensive chips to run complicated instructions.
The RISC processor also has less instruction which is not as complicated as the CISC
processor. The reduction of the instruction improved the speed of the processor which
enables the processor to execute instructions more quickly. The RISC processor is also
cheaper and has greater emphasis on the efficient writing of software with the instructions
that are available.
However, because the RISC only use simple instructions, this means that the instructions
can be executed within clock cycle. Also because the RISC has less software support, this
created lots of setback for them.
Many commercial companies are unwilling to take the risk of using the RISC because for the
new processor it was and also because the recognition in the market was low so they.
In conclusion, I think both processors have their own avenges and disadvantages and at the
end of the day they both do the job we require them to do, but personally I would prefer to
use RISC because it simpler and much faster than CISC and its more reliable.
@Coventry University
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6. Version 1
References
Websites:
Date visited: 6/12/2013
< http://www.eastaughs.fsnet.co.uk/cpu/further-ciscrisc.htm >
Date visited: 04/12/2013
< http://www-cs-faculty.stanford.edu/~eroberts/courses/soco/projects/risc/risccisc/ >
@Coventry University
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7. Version 1
References
Websites:
Date visited: 6/12/2013
< http://www.eastaughs.fsnet.co.uk/cpu/further-ciscrisc.htm >
Date visited: 04/12/2013
< http://www-cs-faculty.stanford.edu/~eroberts/courses/soco/projects/risc/risccisc/ >
@Coventry University
Page 6