problem 1:

a) Differentiate clearly between the given forms of memory:

• RAM
• ROM
• PROM
• EPROM
• Cache

b) Identify the two main bus configurations normally found in a PC. Describe why one has a limiting factor that affects the overall performance of the computer.

c) Describe the concept of virtual memory and how it works.

problem 2:

a) describe the new storage systems that have appeared since diskettes and hard drives. Describe why there has been this need for rapid enhancements and the opportunities they provide.

b) A computer system might be describeed as MULTI-MEDIA. Describe what this means and list the hardware components likely to be found in such a system, both inside and outside the main case.

problem 3:

a) Printers used with personal computers have various characteristics from those normally found in large-scale systems. Distinguish between the two types.

b) Choose a printer appropriate for printing the master copy of an examination paper. Describe why it is appropriate and describe the mechanics of its operation.

c) Choose a different type of printer {from that in (b)} appropriate for printing utility bills sent out to over a million consumers. Describe why it is appropriate and also how this printer works.

problem 4:

a) Describe what is meant by the data structure LINKED LIST.

b) Describe how a linked list can be implemented in memory using a 2-dimensional array. [4]

c) A 2-dimensional array called N already contains student ID numbers in linked-list format so that they are in ascending order. Suppose that the list is not empty. Two variables contain necessary information.

DATUM holds the row number of the lowest number.
LAST holds the row number of the last physical entry in the table that is, row (LAST+1) will contain no data.

i) Draw up an algorithm (flowchart or pseudo-code) to display an ascending list of student IDs.
ii) Draw up an algorithm (flowchart or pseudo-code) to input a new ID and add it logically to the linked list.

problem 5: For each of the given input devices, illustrate:

• What the user needs to do before data capture
• Any limitations imposed on the data
• How the hardware itself reads the data

a) Barcode reader (borrowing and returning books in a library).
b) Magnetic stripe reader (ATM cards).
c) Optical mark recognition reader (for marking exam papers).
d) Touch screen (providing tourist information).

problem 6: Below are four illustrations of assembly-language code.

a) LDA ORDER LOAD the contents of memory address labeled ORDER.
b) SUB DISC SUBTRACT contents of memory address DISC from the number in the accumulator.
c) BNZ LOOP1 Check accumulator. If the content is non-zero, branch to label LOOP1 the next instruction.
d) BRN LOOP2 Branch to label LOOP2 unconditionally.

For each of the above, describe IN DETAIL the series of events which takes place throughout a SINGLE fetch-execute cycle. In each case and at each phase describe how the registers CIR, MAR, MDR/MBR, PC(SCR) and ACCUMULATOR change.