The Mixed Mode Manager manages the mixed-mode architecture of PowerPC processor-based computers running 680x0-based code (including system software, applications, and stand-alone code modules). The Mixed Mode Manager cooperates with the 68LC040 Emulator to provide a fast, efficient, and virtually transparent method for code in one instruction set architecture to call code in another architecture. The Mixed Mode Manager handles all the details of switching between architectures.
The Mixed Mode Manager is intended to operate transparently to most applications and other software.
Although Mac OS X will not run 68K code, Carbon will support universal procedure pointers (UPPs) transparently, so you do not have to change them or remove them from your code. You may want to keep Mixed Mode Manager calls in your application to maintain compatibility with the current version of the Mac OS. Mixed Mode Manager calls from Carbon applications running on Mac OS 8 or 9 will function normally.
The Mixed Mode Manager was used by developers who
wanted to recompile their applications into PowerPC code and their applications passed the address of some routines to the Mac OS using a reference of type ProcPtr
created applicationswritten in either PowerPC or 680x0 codethat support installable code modules that might be written in a different architecture
wrote stand-alone code (for example, a VBL task or a component) that could be called from either the PowerPC native environment or the 680x0 emulated environment
wrote debuggers or other software that needed to know about the structure of the stack at any time (for example, during a mode switch)