as64 is yet another 6502 cross assembler. I decided to archive the source code of some very old (mid-late 80's) projects of mine before the original magnetic media gave up the ghost. These projects were written in assembly language targetting the Commodore 64. At the time, I was using Chris Miller's "Buddy Assembler" on a Commodore 128 to build the software. I thought it would be handy to be able to build this old software on modern hardware, but I wasn't able to find an existing 6502 cross assembler that supported the original assembler's syntax for temporary labels (e.g. '+' and '-').

Staring down tens of thousands of lines of vintage source code that I did not wish to manually edit to uniquely name every branch target, and having some free time, I decided to write an assembler that supports at least the subset of Buddy Assembler features that I was using circa 1987-89.

as64 is written in C++14 and has no dependencies other than the C and C++ standard libraries. I've tested it on Ubuntu 18.04 LTS using gcc and on the Mac using clang. It should also work on Windows, although it has not been tested there.

Building

Build files for cmake are provided. Best practice is to build outside of the source tree:

cd as64
mkdir out
cd out
cmake ..
make

If you don't have cmake (or don't want to use cmake), you can also throw all of the .cpp and .h files from /src into your favorite IDE and hit build; there are no particular compiler or linker settings needed.