What is Assembler

How assembler works


An assembler translates assembly language into machine code

Assembling Process


A SIC/XE source program looks like this


A Intermediate file looks like this


An object file looks like this


  • Pass-1:
    1. Define symbols and literals and remember them in symbol table and literal table respectively.
    2. Keep track of location counter
    3. Process pseudo-operations
  • Pass-2:
    1. Generate object code by converting symbolic op-code into respective numeric op-code
    2. Generate data for literals and look for values of symbols