assembler

a two-pass assembler implementation in ansi c that processes assembly language files.

what's included

• project specifications (pdf file in this directory)
• complete assembler source code
• makefile for building

how it works

the assembler processes .as files through these stages:

preprocessor - handles macro definitions and expansions, creates .am files

first pass - builds symbol table, assigns addresses to labels, validates syntax

second pass - resolves symbol references, generates machine code, produces output files

happiness 😇 or sadness 😭

build and run

make
./assembler filename1 filename2 ... # files must be in .as format

output files

• .am - trimmed file with macros expanded
• .ob - object file with machine code
• .ent - entry symbols
• .ext - external symbols

memory layout

• 256 words max memory
• 10-bit words
• instructions start at address 100
• data follows code section

file structure

key files:

• assembler.c/h - main driver
• preprocessor.c/h - macro handling
• first_pass.c/h - symbol table construction
• second_pass.c/h - code generation
• symbol_table.c/h - symbol management
• instruction_image.c/h - instruction encoding
• data_image.c/h - data directive handling