DS80C310

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time. In the DS80C310, the MOVX instruction takes as little as two machine cycles or eight oscillator

cycles but the “MOV direct, direct” uses three machine cycles or 12 oscillator cycles. While both are

faster than their original counterparts, they now have different execution times. This is because the

DS80C310 usually uses one instruction cycle for each instruction byte. The user concerned with precise

program timing should examine the timing of each instruction for familiarity with the changes. Note that

a machine cycle now requires just four clocks, and provides one ALE pulse per cycle. Many instructions

require only one cycle, but some require five. In the original architecture, all were one or two cycles

except for MUL and DIV. Refer to the High-Speed Microcontroller User’s Guide for details and

individual instruction timing.