As far as assemblers go, I've done a partial port of gpasm to CodeWarrior,
but it currently runs only under OS X. It probably would work under OS 9,
but I've never tested it.

It also requires Metrowerks CodeWarrior Pro 8 (well, at least that's all
I've tested), and it's probably not worth using if you don't already own CW.

I say it's partially ported because, although it assembles and displays
errors using the CW error-reporting mechanism (which makes it very easy to
get to the line in the source causing problems), you can't set any of the
command-line options (yet).

I'm also working on porting gpsim and SDCC to the CW environment.

Note that all of the GNU Pic tools can be built & used under OS X as
command-line tools, although some compile more easily than others.

--
Rick

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