Motorola 68008 (MC68008) microprocessor belongs to the first generation
of 68000 microprocessors. The 68008 is
fully object-code compatible with the 68000, but not pin-compatible
with it. The 68008 has 8-bit data bus, and, depending on packaging, it
may have 20-bit or 22-bit address bus. Because the processor has smaller
address and data buses, it doesn't require as many signal pins as the
68000 microprocessor and could be manufactured in smaller packages:
- The 68008 microprocessor in 48-pin ceramic or plastic DIP package
can address up to 1 MB of memory.
- The processor in 52-pin PLCC package can address up to 4 MB of memory.
Due to smaller size of the data bus the Motorola 68008 needs twice as
many fetches to read instructions and data - this makes the CPU slower
than the 68000 microprocessor running at the same frequency.
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