Experimental CC65 C Support for MEGA65 C65 Mode
This is a very minimalistic first step to target the C65 mode on MEGA65 with the CC65 toolchain. I followed the "customizing" steps but didn't take care of interrupt/vectors yet:
https://cc65.github.io/doc/customizing.html
I chose the zeropage ($18-$31) and RAM ($0500-$0FFF) locations experimentally and based on what I gathered from the PDF at: https://65site.de/map.php
There is no file i/o or any C stdlib support yet. This is only suitable for some baremetal tests (like in the example folder). The next step would be to unmap BASIC 10, because it makes a large amount of the 64kB area non-executable. Also, a malloc implementation should be added that makes use of the higher memory areas, and the usable parts from the C64-side MEGA65 clib should be pulled in.
Building c65.lib
Edit the path to cc65 in build.sh and run it.
Building and running the example
Edit the path to cc65 in example/build.sh and run it.
Load the resulting example.prg to your MEGA65 in C65 mode (see example/run.sh) and enter SYS 1280 to start it (or g500 in the monitor).
License: MIT
Copyright 2020 Lukas F. Hartmann
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