[Pammy]

Hi I've got my computing prelim on Monday and was reading over some questions I should know. Could someone pls help me ??

1. Give two reasons why a computer is often called a "two state" machine.
2. Explain how 2's compliment works
3. Explain the term "addressability"
4. Give two advantages of having an operating system in RAM rather than ROM.
5. Explain the purpose of a bootstrap loader.
6. Explain the difference between a spooler and a buffer, and give an example where a spooler would be used in preference to buffer.
7. What is the approximate capacity of a standard DVD and CD?

Sorry I know there's a lot but I would appreciate some help
Thankyou
Pamela

[coca]

5.

A bootstrap loader is a piece of code found on a section of memory of a device that runs in order to load the operating system. The term comes from "pulling yourself up by your bootstraps", I believe.

When the computer starts up, the BIOS will look for a bootstrap loader on a device connected to the system, you can configure the BIOS to edit the order in which it checks the devices, for example: floppy disk first, then CD, then hard disk.

The bootloader program has a special signature so that the BIOS knows that it's a valid program. After it has been validated, it starts execution of the bootloader code, which usually just means it switches processor mode, loads the initial OS code, then jumps there to continue execution. The bootloader program cannot exceed a certain length (the size escapes me, but I think it *must* all fit on one sector of the disk).

Hope this helps! I only attempted this question because the others are boring. :b

[Pammy]

Thanks very much
But aren't they all boring
Pam xxxxx

[coca]

I suppose!

[Nathan]

1. Give two reasons why a computer is often called a "two state" machine.

ive never done computing before but have seen the question answered on here somewhere...its cause it works on the principle of either being on or off (1 or 0), therefore in two states

*i think*

[Pammy]

Thank you for your help
Pam xx

[xkarenx]

2.
(Do you want to know how to use two's complement or are you asking for the whole logic behind it?)

3.
The term addressability means the ability of the processor to write data to any memory location and read data from any memory location.


4.
Operating systems in RAM can be changed/updated. (That's all I can think of at the moment)

6.
A buffer is a temporary storage location in an interface for storing data to be transferred between the processor and peripherals. Peripherals tend to work at a slower rate than the processor so the buffer is used to hold the data until the peripheral can take it meaning the processor is free to return to other tasks instead of waiting for the peripheral which would be inefficient. A spooler on the other hand stores data for transferring to a peripheral on backing storage such as a hard drive. This technique is used with printers for storing documents that are queuing to be printed.


7.
CD - 650 MB
DVD - 4.7 GB

[Pammy]

Thank you soooo much
That has been a gr8 help
Pam xx

[John]

1. Give two reasons why a computer is often called a "two state" machine.

A computer is often called a "two state" device as in it's simplist form, all instructions are either 1 or 0

2. Explain how 2's compliment works

Two's complement works by addressing the far most left digit as a negative power of 2, and the remainder of the series of binary digits are positive powers of two. By doing this it only allows for one value of zero.

To compute a number in Two's Complement you would add the positive powers of 2 to the negative power of two, or to zero if the negative power of 2 is set to 0.

eg. -128 in Two's Complement would be "10000000"
-124 in Two's complement would be "10000100", since -128 + 4 = -124

3. Explain the term "addressability"

Addressabilty is the ability for the processor to give each memory location a unique address for easy access. This also prevents one memory location being used twice at the same time.

4. Give two advantages of having an operating system in RAM rather than ROM.

Storing the OS in RAM gives the possibility of system files being Updated.

Another advantage would be that the Operating System can be changed for a diffrent OS.

5. Explain the purpose of a bootstrap loader.

A more simplistic approach here:

A Bootstrap loader is a small pice of coding found in ROM (AKA BIOS/CMOS) which has one main purpose, to load an operating system into memory.

6. Explain the difference between a spooler and a buffer, and give an example where a spooler would be used in preference to buffer.

A buffer is RAM which is specific for the purpose of tempory storage of data being transffered between two devices. A spooler is a pice of software with will use an area of a computers RAM to act like a buffer, but the user can have much more control over it. A spooler is most likely to be used in a networking enviroment rather than a buffer.

7. What is the approximate capacity of a standard DVD and CD?

CD - 650MB and 700MB (800MB and i think 900MB versions exist, but are hard to come by)

DVD - 5GB(Single Layer), 10GB(Dual Layer)


Hope that helps

[coca]

5. Explain the purpose of a bootstrap loader.

A more simplistic approach here:

A Bootstrap loader is a small pice of coding found in ROM (AKA BIOS/CMOS) which has one main purpose, to load an operating system into memory.

More likely to be found on the MBR :b

[John]

5. Explain the purpose of a bootstrap loader.

A more simplistic approach here:

A Bootstrap loader is a small pice of coding found in ROM (AKA BIOS/CMOS) which has one main purpose, to load an operating system into memory.

More likely to be found on the MBR :b

At Higher level the answer i gave is suffice!

[coca]

5. Explain the purpose of a bootstrap loader.

A more simplistic approach here:

A Bootstrap loader is a small pice of coding found in ROM (AKA BIOS/CMOS) which has one main purpose, to load an operating system into memory.

More likely to be found on the MBR :b

At Higher level the answer i gave is suffice!

Would they mark that as correct? o.0

Shocking!

[John]

5. Explain the purpose of a bootstrap loader.

A more simplistic approach here:

A Bootstrap loader is a small pice of coding found in ROM (AKA BIOS/CMOS) which has one main purpose, to load an operating system into memory.

More likely to be found on the MBR :b

At Higher level the answer i gave is suffice!

Would they mark that as correct? o.0

Yes, you don't go into much detail about it.

You simply learn what it's purpose is, where it is likely to be stored(RAM or ROM).

You have been at Uni too long buddy

[coca]

5. Explain the purpose of a bootstrap loader.

A more simplistic approach here:

A Bootstrap loader is a small pice of coding found in ROM (AKA BIOS/CMOS) which has one main purpose, to load an operating system into memory.

More likely to be found on the MBR :b

At Higher level the answer i gave is suffice!

Would they mark that as correct? o.0

Yes, you don't go into much detail about it.

You simply learn what it's purpose is, where it is likely to be stored(RAM or ROM).

You have been at Uni too long buddy

Lol

We haven't covered this kinda stuff at uni yet, still wasting time on doing maths. :/

[Dave]

dont think i told you that at strath as of next year there will be no maths for comp sci in first year and they are undecided if you will do the classes in second year instead or not at all. I dont think its right really because maths is very heavily involved later on in the course and computer science in general

Stats and discrete maths will still be done though.

[coca]

Oh really?

Great choice!

[John]

I may be going to Glasgow now, hmmm

[Pammy]

Thanx very much for all of your help evry1 !!!
Hopefully I mite b able2 scrape a pass now !!
Pam xxxx

[John]

no problem