ilmenit/atari-800-skills/mads

MADS Assembler

MADS, also called Mad-Assembler, is a cross-assembler commonly used for Atari 8-bit development. Its syntax is close to XASM/QA/FA, with additions for local and temporary labels, macros, procedures, typed data, virtual and hardware memory banks, relocatable output, SpartaDOS X files, and WDC 65816 code.

Use this skill when writing, reviewing, porting, or debugging MADS assembly. Prefer the smallest reference file that answers the question.

Quick Start

• For command-line assembly, output files, listings, and exit codes, read

references/usage.md.

• For comments, line joining, mnemonic chaining, numbers, strings, expressions,

and operator precedence, read references/syntax.md.

• For ordinary assembler directives such as .ORG, .BYTE, .WORD, .DS,

.VAR, .ZPVAR, .IFDEF, .REPT, .PRINT, .ERROR, .LEN, .SIZEOF, .DEFINE, and .UNDEF, read references/directives.md.

• For XASM-style pseudo-commands such as OPT, ORG, INS, ICL, DTA,

SIN, COS, RND, IFT, ELS, ELI, and EIF, read references/pseudo-commands.md.

Reference Map

Orientation

• references/introduction.md: what MADS is, how it

relates to XASM, compilation notes, and MADS vs XASM differences.

• references/mnemonics.md: supported 6502, illegal

6502, 65816, and mnemonic-extension notes.

• references/cpu-detection.md: compile-time CPU

detection symbols.

Assembly Control and Syntax

• references/control.md: high-level assembly control,

conditional assembly pointers, and zero-page assembly behavior.

• references/code-generation-directives.md:

#IF, #WHILE, and #CYCLE code-generation directives.

• references/directives.md: dot directives.
• references/pseudo-commands.md: legacy-style

pseudo-commands.

• references/macro-commands.md: built-in macro

commands such as MVA, MWA, ADW, SBW, branches, increments, moves, and compares.

Names and Scope

• references/labels.md: anonymous, local, global,

temporary, self-modifying, and MAE-style labels.

• references/local-areas.md: .LOCAL / .ENDL

scoped areas.

Abstractions and Data

• references/macros.md: .MACRO declarations, parameter

syntax, generated labels, and calls.

• references/procedures.md: .PROC declarations,

calls, .REG/.VAR, and typed parameters.

• references/data-types.md: .STRUCT and .ENUM.
• references/arrays.md: .ARRAY declarations and access.
• references/memory-banks.md: virtual memory banks

with OPT B- and hardware memory banks with OPT B+.

Linking and Output Formats

• references/relocatable-code.md: router for .RELOC, external and public symbols, .LONGA, .LONGI, and .LINK.
• references/spartadosx.md: SpartaDOS X executable

file blocks, relocation/update/definition blocks, and SDX programming notes.

Authoring Guidance

• Use MADS-native constructs when they clarify Atari 8-bit code: named local

areas, .PROC, .STRUCT, .ARRAY, and macro commands are expected in MADS projects.

• Preserve source compatibility when porting from XASM: check

references/introduction.md before changing syntax that XASM and MADS treat differently.

• For examples involving 65816 accumulator or index width, verify the relevant

mode directives in references/relocatable-code.md and mnemonic support in references/mnemonics.md.

• When diagnosing assembly output, inspect both the command-line options in

references/usage.md and the output-affecting OPT / ORG / INS / ICL / DTA behavior in references/pseudo-commands.md.

Reference Layout Notes

The bundled references/ files are the self-contained assembler reference for this skill. Load only the specific reference file needed for the task, and keep topic work in the Atari router files unless the user is specifically asking about MADS syntax, directives, relocation, or SpartaDOS X output.