Check whether your code gets called by writing a main that doesn’t use any traps but just loops clearing the screen, fills it with black, clears it, etc. If it

Check whether your code gets called by writing a main that doesn’t use any traps but just loops clearing the screen, fills it with black, clears it, etc. If it doesn’t get called, disassemble the startup code. It can’t be long. I would use a version of ResEdit that has a built-in disassembler (advantage: you won’t have to run that on a 512k Mac, but can use a beefier one or an emulator) You also may want to use the earliest version of CodeWarrior you can find, as support for System 6 may have stopped at some time.