Freescale 68LC040

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The 68LC040 is a low cost version of the Freescale 68040 microprocessor with no FPU. This makes it less expensive and draw less power. Although the CPU now fits into a feature chart more like the 68020, it continues to include the 040's caches and pipeline and is thus significantly faster than the 020.

Some mask revisions of the 68LC040 contained a bug which prevents various software FPU emulators from operating correctly. These revisions are typically found in 68LC040-based Apple Macintosh computers. The bug triggers if an FPU instruction which would trigger an exception resides at the end of a page, and the next page is swapped out. In that case, the CPU will page fault with the PC pointing at that FPU instruction, and then fail to trigger the FPU exception, leading to a variety of errors.

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In keeping with general Freescale naming, this CPU is often referred to as the LC40.de:Motorola 68LC040 es:Motorola 68LC040 it:Motorola 68LC040 pl:MC68LC040