A comiler produces object code/ excutable file An interpreture does not produce an object code An interpreture analyses a program line by line whereas a compiler does the whole block of code A compiler will not procuce an executable file if an error is found but an interpreture will run the code until the first error is detetced Interpreted code will excute slower than excuting the object code produced by a complier Do not need a compiler to excute a compiled program but when running interpreted code the interpreture always needs to be present Once compiled source code is no longer needed to run the program but an interpreture always needs source code at runtime Compiled code can only excute on a machine with the same processor type whereas interpreted code is more portable

- Give the differences between source code and object code

Source code is written in high-level or assembly language whereas object code is written in machine language + all differences between high and low level languages, such as: - Source code is easy to understand - Source code is easy to modify - Source code contains fewer statements than object code

What type of translator can be used to translate assembly language into machine code?

Assemblers

Which two types of translator can be used to translate high-level languages into machine code?

Compilers Interpreters

Which type of translator translates high-level languages into machine code line-by-line?

Interpreters

Why does the computer use translators?

In order for a program to be executed by a computer’s processor, it must be in the form of a machine code program

What are the 3 types of translator called?

Interpreter Assembler Compiler

Which type of translator translates high-level languages into machine code in one go?

Compilers

Which type of translator requires the source code to be present when the program is executed?

Interpreters

Which type of translator has procedures to translate each kind of program instruction?

Interpreters

What is source code?

Code written using a human-readable programming language

What is object code?

Code written in machine langauage through translators

What is an intermediate language?

'Half way' standard language which can they be translated into computer specific machine code

What is the benefit of using compilers with intermediate languages?

They allow the program to be run on all platforms

How do compilers with intermediate languages work?

1. Translate the program into the intermediate language 2. Platform specific translator translates this intermediate language code

What is a compliler

A program that translates high level languages into machine code in one go

What is an interpreter

A program that translates high level languages into machine code line by line

What is an assembler

A program that comverts from low level programming code to machine code

Explain how a compiler better protects source code to an interpreture?

A copied file of the code is used to to run the program not the actual source code

Discuss the advatanges of using a high level language compared to a low level

Program code is easier to understand/maintain/debug; Faster development time // programmers can be more productive // one line of HLL code can do the same job as many lines of assembly language; Programs are (more) portable (to other hardware platforms) Language is problem-oriented; More support/ better refined as more programmers use it; Support for different paradigms; A. Examples eg functional programming Built-in support for data structures; A. Example(s) eg arrays, records Availability of flow control structures; A. Example(s) eg loops, selection Improved features for supporting modularity; A. Ability to use subroutines

Discuss the disadvatages of using a high level language compared to a low level (Assembly language)

Assembly language code may execute more quickly is because translation is not required Assembly language code may use less memory; Assembly language gives direct/better access to computer hardware // enables direct manipulation of memory (contents);

Which type of programming language is this? 01010101 11010110 01001011 10110110

Machine Code

Which are processor specific: low-level languages or high-level languages?

Low-level languages

Which type of language uses mnemonics in instructions?

Assembly language

Which type of languages must be translated into machine code with a compiler or interpreter before execution?

High-level languages

What are the two types of low level langauge?

Machine code Assembly language

Describe machine code langauage

Programming with the use of numerical characters

Describe assembly langauage

Programming with the use of mnemonic characters

Explain the term ‘imperative high-level language’

A programming language that requires programming discipline. Programmers must develop a proper order of actions in order to solve the problem. A 'procedural language' BETTER: (1) Instructions are executed in a programmer-defined order (1) High level language instructions use English-like keywords

What is a function?

A method that returns a value

What is a procedure?

A method that does not return a value

If you were to want a random number between 0 and 10, how would you go about programming one?

Random random = new Random(); int randomNumber = random.Next(0, 10); Console.WriteLine(randomNumber);

State how to declare a 2D array

Int[,] array = new int[x, y];

State how to declare an array of integers

Int[] array = new int[6];

How would you acess the eleemts of a text file

String filename = "FILENAME.txt"; StreamReader sr = new StreamReader(filename); while ((line = sr.ReadLine()) != null) { line = each line of text file } sr.Close();

What does the '%' operand do?

Gives the remainder of a division of two numbers

What does an integer '/' operand do?

Divides two integers and rounds towards zero to give an integer

Math.Round(x,y,z)' What are the variables for x y and z What do they represent in the rounding function

X: Decimal number to be rounded y: Integer, number of decimal places z: Mode, Specification for how to round x if it is midway between two other numbers

What are the advantages of using named constants

Easier to understand code

Porgram how to get the poisition of an element of a string

String Str = new string; Str[position]

How would you program a substring Substring

What is meant by a subroutine

A named block of code containing a set of instructions desgined to perform a frequenctly use operation

What are two advantages of constants over hard coded values?

Constants can be given names so are easier to for a human to read Constants only need updating at one position in the code

What is meant by concatenation

Joining two or more strings together

Can you say the 4 types of programming paradigm?

Imperative / procedural Functional Declarative Object oriented

What does the ALU do?

Performs arithmetic and logic operations

What are the 3 stages to the fetch section of the Fetch-Execute cycle ?

1. Any data required by the instruction that isn’t present in registers is fetched 2. The instruction is carried out 3. Results of any calculations are stored in general purpose registers or main memory

What is the role of the control unit?

Controls all the differnt parts of the processor

Why are registers really effective for the CPU?

The CPU needs very fast accessible memory and registers are vert fast memory

What are the 5 special purpose registers?

PC (Program counter) CIR (Current instruction register) MAR (Memory address register) MBR (Memory buffer register) SR (Status register)

What does the special register PC do?

Used to hold the memory address of the next or the current instruction to be executed in the fetch-execute cycle Must say both current and next ^

What does the CIR register do?

Holds the instruction that is currently being executed by the processor

What does the memory address register do?

Stores the memory address of a memory location that is to be read from or written to

What does the special MBR register do?

Holds the contents of a memory location that has been read from or data that is to be stored.

What does the status register register do?

Contains a number of bits, the values of which can change to indicate the occurrence of an interrupt.

What does the SR special purpose register stand for?

Status register

What do the special purpose registers MBR, MAR and CIR stand for?

Memory buffer register Memory address register Current instruction register

What does the system clock do?

Synchronises the components

What is a register?

A memory/storage location inside the processor

By how much would adding just one wire to the address bus increase the memory size

No. wires X 2^1

What mathematically effectively is logic shifting

Doubling or halving

How would you describe what is happening in the AQA assembly language: LDR Rx, <memory reference>

Loading the value stored in the memory location specified by <memory reference> into register x.

Describe what a word is to the processor

The group of bits that is treated as a single unit by the processor

What is the AQA assembly language for the logical OR statement

ORR

What is a core responsible for in a processor?

Completing the Fetch-Execute cycle

How would you write 'Logically shift right the value stored in register y by the number of bits specified by <operand> and store the result in register x' in AQA assembly language

LSR Rx, Ry, <operand>

What 4 ways can the processor execute data?

Reading operand data in to the accumulator from the RAM Performing arithmetic on operand data Performing logical functions (conditionals / loops) Writing data from the accumulator to the RAM

What is the Logical XOR AQA assembly reference

EOR

What is the role of the processor?

To execute program instructions in order to run applications

What is the operation for the AQA assembly language 'MVN'

Logical NOT

Name two types of main memory

1. Random access memory (RAM) 2. Read only memory (ROM)

Discuss the advatanges of using a high level language compared to a low level

Program code is easier to understand/maintain/debug; Faster development time // programmers can be more productive // one line of HLL code can do the same job as many lines of assembly language; Programs are (more) portable (to other hardware platforms) Availability of flow control structures; A. Example(s) eg loops, selection Improved features for supporting modularity; A. Ability to use subroutines Built-in support for data structures; A. Example(s) eg arrays, records Language is problem-oriented; Support for different paradigms; A. Examples eg functional programming

Discuss the disadvatages of using a high level language compared to a low level

Assembly language code may execute more quickly; R. If response suggests that faster execution is because translation is not required Assembly language code may use less memory; Assembly language gives direct/better access to computer hardware // enables direct manipulation of memory (contents); NE. “More efficient” for either executes more quickly or uses less memory

What type of quantities would you describe real numbers as?

All possible real world quantities

What type of number should you use for counting on a childs number line? (1-10)

Natural numbers