Motorola 68010

A microprocessor from Motorola. It was the successor to the Motorola 68000 and was followed by the Motorola 68020. Some instructions which were previously user mode were made system mode, which necessitated patches to a few programs. The 68010's main advantage over the 68000 was that it could recover from a bus fault. The 68000 microcode didn't save enough state to restart all instructions; the 68010 corrected this fault. This allowed it to use paged virtual memory. The 68010's DBxx (decrement and branch) instructions could hold and execute the preceding instruction in the prefetch buffer, allowing some two-instruction loops to execute without refetching instructions. At one time there was a 68010 variant that was pin-for-pin compatible with the 68000. Early Amiga hackers replaced their 68000s with 68010s in order to get a small performance increase.

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