2.5 translators and facilities

2.5 translators and facilities

1. translators

   • compiler
     • translates source source code from high level language into object code and then in to machine code ready to be processed by the CPU.
       • the whole program is translated into machine code before it is run.
     • advantages
       • no need for translation software at run time and no need to share original source code
         • speed of execution is faster because code is usually optimised
     • disadvantages
       • you cannot compile the program if there are syntax errors anywhere in it which can make it tricky to debug
         • if you change anything you need to recompile the code
   • assembler
     • assembles assembly language into machine code. translates the whole code before execution
   • interpreter
     • translates source code from high level languages into machine code ready to be processed by the CPU. the program is translated line by line as the program

2. levels of programming languages

   • machine code 1st generation
     • binary representation of instructions in format that the CPU can decode and execute.
       • have an operation code (opcode) instructions and address or data to use (operand)