Really crude assembler for the simple computer.

See main README for a description of all the available instructions and pseudo instructions provided by the assembler.

Features:

Parses a text based description of a program, and assembles into a little-endian binary file
Label address calculation
Maintains two reserved SYMBOLs that can be referenced
- CURRENTINSTRUCTION: contains the memory address of the current instruction
- NEXTINSTRUCTION: contains the memory address of the next instruction relative to the current instruction
Writes output as little-endian binary data

Usage

  -i string
        input file (default: stdin)
  -o string
        output file (default: stdout)
  -s    output assembly as string

Example:

go run github.com/djhworld/simple-computer/cmd/assembler -i myprogram.asm -o myprogram.bin

Note you can see the output of the assembler as a string for debugging purposes by passing the -s flag

Example:

go run github.com/djhworld/simple-computer/cmd/assembler -i myprogram.asm -s

Assembler directives

Labels can be defined by an alpha-numeric sequence of characters followed by a colon, e.g.

MAIN:
   <instructions>

Symbols can be defined by a percentage sign % followed by an alpha-numeric sequence of characters, an equals sign = and a numeric value

%LINE-WIDTH = 0x001E
%ONE = 1
%DISPLAY-ADAPTER-ADDR = 0x7