Current version: 1.0.1
Freeware
Requires Merlin 16+
Merlin 16+ is a great assembler for the Apple IIgs, but the suite of macros that are included with it don't include very good macros for making GS/OS calls. In addition, the macros included with the assembler are missing the newest GS/OS calls added to System 6.0 and System 6.0.1.
My Merlin GS/OS Macro package provides new macros to make it easy to make GS/OS calls from Merlin 16+ assembly code. Just add a copy of the EDS.GSOS.MACS file to your Macro.Library folder, then use the MacGen utility to add them to your macro file for your project.
Once you've done so, making a GS/OS call is as simple as:
OpenGS openParms
The operand openParms is a pointer to the parameter list for the class 1 GS/OS call OpenGS. That's all there is to it!
If you need macros for System 6.0 and 6.0.1, check out my Merlin System 6 Macros set, also available here on my site.
On May 3, 2015, I updated the macro file with some comment changes, but no functional difference. There’s no need to re-download if you already use this macro file.