Unit 2.5 Translator and Facilities

Unit 2.5 Translator and Facilities

1. Key Words

   • Opcode
   • Operand
   • Translator
   • High Level Code
   • Low Level Code
   • Assembly Language
   • Assembler
   • Instruction set
   • Source code

2. Generations

   • 1st Generation
     • Machine Code
       • Directly executable by the processor
         • The Generation that "computer understands"
           • Difficult to program in, hard to understand, hard to find errors
   • 2nd Generation
     • Assembly Code
       • Use mnemonics
         • Easier to program in than 2nd Generation but still difficult
           • One Assembly Language instruction translates to one Machine Code Instruction
             • (1-1 relationship)
               • Needs to be translated into Machine Code for the computer to be able to execute it
                 • Uses an Assembler
                   • Assembler assembles assembly language
     • Debug means to go through the code to search for where/why an error has occurred
     • Device Drivers
       • Loaded into memory by the Operating system and used to control the operation of a hardware device like Graphics card drivers and Printer Drivers
   • 3rd Generation
     • Easier to understand
       • Easier to find errors, easier to debug
         • Uses English-Like Keywords
           • One instruction translates into many machines code instructions
             • Examples; Java, Basic, Pascal, C++
               • Complier
               • Interpreter
   • 4th Generation
     • Declarative Language
       • Facts and Rules are stated
         • Describes what computation should be performed and not how to perform it
           • SQL
           • Expert Systems
           • Artificial Intelligence