Package atasm

6502 cross-assembler

http://atari.miribilist.com/atasm/

ATasm is a 6502 command-line cross-assembler that is compatible with the
original Mac/65 macroassembler released by OSS software. Code
development can now be performed using "modern" editors and compiles
with lightning speed.

General Commands (Section 1)
atasm
atasm assembles 6502 code to an Atari DOS executable, an Atari XFD disk image, or a raw binary file. The syntax used is compatible with the Atari 8-bit...