3 ms·
Yeah, same here. I don't have any intimate knowledge of it personally, but I do know it shipped on the ROM in the 601 era. Given its size, I wonder how much of
by benjaminpv 5y ago
Yeah, same here. I don't have any intimate knowledge of it personally, but I do know it shipped on the ROM in the 601 era. Given its size, I wonder how much of it is an emulator and how much a translator between the 68k and PPC toolbox calls. The early Macs are famous for doing tricks with memory to fit everything in the extremely limited work RAM, so I'd bet there's some MMC trickery in there as well.
- phire 5y agoHow much PPC toolbox actually existed on that first PowerPC mac? My understanding is that the ROM is mostly OpenFirmware (which is forth bytecode), the nanokernel (aka the 68k emulator) and a mostly unmodified 68k toolbox.
- duskwuff 5y ago"Mixed Mode Magic" was a key feature of the 68k emulator. 68k code could call PowerPC routines through "universal procedure pointers", and vice versa. This included Toolbox routines as well as third-party code, and it extended to the point that 68k CDEFs (system extensions) which patched system traps could still be used on PowerPC systems. Some further details are at: https://orangejuiceliberationfront.com/universal-procedure-pointers/ https://orangejuiceliberationfront.com/universal-procedure-p...