COMM005 Information Systems Development Coursework 2018-19:

This is an individual exercise which contributes 40% of your total COMM005 mark and must be
completed and handed in by 4pm (16.00) on Tuesday 11th December, 2018. It MUST be handed
in electronically via Surrey Learn in Acrobat pdf format. (You are advised to aim to hand the work
in earlier to avoid delays caused by system/uploading problems.) Feedback and marks will be
provided after the Christmas break, before the written examination. Plagiarism or copying is not
permitted, of course. This assignment sheet consists of 2 pages.

It is perfectly OK to use a drawing package such as MS-Powerpoint, MS-Paint, MS-Word, or MS-
Visio, or, if you prefer, to use a CASE tool, such as UMLet (used in the lab sessions) to produce
these diagrams or you may even submit your diagrams as (clear!) hand drawings (embedded in pdf)
if you prefer. Beware: some CASE tools do not always follow the 'correct' syntax (see note below!)

IMPORTANT: For all the exercises, you MUST follow the diagram syntax and
terminology as presented in the lectures, and as given in Tegarden, Dennis &
Wixom (2013, 4th edition), the course textbook (or 3rd edition, 2010, or 5th, 2015).


The Spectrum, Commodore and Amstrad were all kinds of vintage computers from the 1980s. Like
all modern computers, they possessed a central processor and memory, the ability to display
colour, and present sound. However, since this was a very active time in the evolution of home
computers, they had other features to a greater or lesser degree. Unless otherwise stated, they
connected to a TV for use as a display.

Six models of the Spectrum (correctly called the ZX Spectrum) were available in the UK: the
(original) Spectrum, the Spectrum 48, the Spectrum+, the Spectrum 128, the Spectrum+2 and the
Spectrum+3. Only the Spectrum+2 had an integrated cassette tape deck; only the Spectrum+3 had
an integrated floppy disk drive. None of these models was supplied with a monitor/display
screen, and an optional joystick could only be directly connected to the +2 and +3.

The Commodore had three main models: the C64, the C128 and a special portable model (the
SX64). Of these, the SX64 was the only one with an integrated display screen, and it was the only
one with an integrated floppy disk drive. With the exception of the SX64, all the Commodore
computers had a special separate (and essential) Commodore tape deck (cassette tape
player/recorder), or a special separate Commodore floppy disk drive as an optional extra. The
tape deck could really be considered to be part of the computer, since it was essential, took its
power from the main computer, and was supplied with it in the retail pack. Both these drives
were external to the main computer. The special cassette drive could not be used with the SX64,
as it was considered unnecessary. Since the SX64 had a built-in colour monitor, it could not be
connected to a TV either. An optional joystick could be connected to all Commodore models.

There were 3 models of Amstrad in the CPC Series: the CPC464 with an integrated cassette tape
deck (and no disk drive), the CPC664, which had an integrated 3 inch floppy disk drive (but no
tape deck), and the CPC6128, which was just like the CPC664, but had more memory. All these
Amstrad models came bundled with a special Amstrad monitor (which was the only screen these
Amstrad computers could use), which had to be plugged into the main computer. This monitor
was actually considered to be part of the computer, since it was essential and took its power
from the main computer. An optional joystick could be connected to all Amstrad models.

SEE NEXT PAGE
Exercise 1.

(a) Create a UML Class Diagram derived from all the information in the above scenario.
Classes should stand for the various computers and their parts. You should show relationships and
other features typical of class diagrams, using the correct syntax (as in the textbook/lectures).
[30%(for classes and relationships)+20%(for other features)=50%]

(b) Explain, in your own words, the structure of the Class Diagram presented as your answer
to Exercise 1a above. You should explain all syntax, clarify meaning and explain why you
have drawn your diagram in the way that you have.
[15%]

Exercise 2.
The Spectrum and Amstrad machines all used a Z80 processor as the CPU. The Commodore
machines had a 6502 processor. The Commodore floppy drives all used 5.25 inch floppy disks. The
Amstrad CPC6128 and Spectrum+3 had 3 inch floppy disk drives. The original Spectrum had 16K
RAM, the Spectrum 48 had 48K RAM; all the other Spectrum computers had 128K memory. The
Amstrad CPC464, Amstrad CPC664, Commodore C64 and SX64 all had 64K RAM. The
Commodore C128 and Amstrad CPC6128 had 128K RAM.

Create a UML Object Diagram using, as a starting point, the Class Diagram provided as your
answer to Exercise 1 plus the information above. You should also add some extra information
obtained from the Internet, citing reference sources (e.g URLs/web addresses). You should also
briefly explain your answer in your own words.
[10%]

Exercise 3.
The Spectrum Next is a new computer, based on the old ZX Spectrum models, but enhanced with
many extra features and brought right up-to-date. It is designed to run all the old Spectrum
programs/games, but will also be capable of running software specially written to use the enhanced
features. It was designed as a Kickstarter project, has been fully funded, and the first fully complete
machines are expected to be delivered to the project backers by the end of 2018, if we're lucky!
[Google it!]

(a)
Consider the Class Diagram that you drew in your answer to Exercise 1. Using information
about the Spectrum Next obtained from the Internet (citing sources), show how you would
add classes regarding this machine to your diagram, including relationships with existing
classes, using appropriate syntax. You can redraw the whole diagram, adding the extra
classes, or just draw a view showing just the new parts, with a clear indication where, and
how, they should be joined to the original diagram. Note: there is quite a lot of information
available regarding this machine, but here you should concentrate on hardware differences
and enhancements (i.e. discussion of games/programs is not required).
[15%]
(b)
Describe in your own words how the new Spectrum Next classes relate to your diagram
that you drew in Exercise 3(a) above, and explain the reasoning for introducing the new
classes and relationships, together with their connections to the existing parts of the diagram.
[10%]
END OF ASSIGNMENT SHEET