Question: Why does the -z option still require you to have init.cmd for the debugger.

Answer: The -z option is for the linker. It specifies which files you want to link in to your code(alternatively, you can specify these files in a linker command file). This has nothing to do with the init.cmd file. The init.cmd file is the file your debugger uses to create a memory map of your target system, so it will know which memory accesses are valid/invalid. The init.cmd file is further explained in Section DB: 7-2. The -t option allows you to specify a memory map of a filename other than init.cmd.