What is the difference between native software and conventional software?
The Power Macintosh runs in two modes, without any further assistance from the user: it can run “native” software, which is software written for the PowerPC chip, or “conventional” software, which is software written for an older 68000, 68020, 68030, or 68040-based computer. Conventional software is sometimes referred to as “68K” software. Conventional software runs in an “emulation” mode, which is functionally similar to the 68020 processor. The main differences between the 68020 processor and later processors are: (a) it does not have a PMMU (Paged Memory Management Unit), (b) it does not support the SWAP16 instruction, and (c) it does not support a floating point unit. The first point is necessary because the PowerPC has a newer, better, memory management model. The second point is also addressed by improvements in the PowerPC chip. The third point requires different steps to work around; see the FAQ question below. Conventional software will generally run faster than a 68020, proba
