64tass v1.59 r3120 reference manual

This is the manual for 64tass, the multi pass optimizing macro assembler for the 65xx series of processors. Key features:

Open source portable C with minimal dependencies
Familiar syntax to Omicron TASS and TASM
Supports 6502, 65C02, R65C02, W65C02, 65CE02, 65816, DTV, 65EL02, 4510
Arbitrary-precision integers and bit strings, double precision floating point numbers
Character and byte strings, array arithmetic
Handles UTF-8, UTF-16 and 8 bit RAW encoded source files, Unicode character strings
Supports Unicode identifiers with compatibility normalization and optional case insensitivity
Built-in linker with section support
Various memory models, binary targets and text output formats (also Hex/S-record)
Assembly and label listings available for debugging or exporting
Conditional compilation, macros, structures, unions, scopes

Contrary how the length of this document suggests 64tass can be used with just basic 6502 assembly knowledge in simple ways like any other assembler. If some advanced functionality is needed then this document can serve as a reference.

This is a development version. Features or syntax may change as a result of corrections in non-backwards compatible ways in some rare cases. It's difficult to get everything right first time.

Project page: https://sourceforge.net/projects/tass64/

The page hosts the latest and older versions with sources and a bug and a feature request tracker.