Instruction Timing

• One “machine cycle” = 6 states (S1 - S6)

• One state = 2 clock cycles

  • One “machine cycle” = 12 clock cycles

• Instructions take 1 - 4 cycles

  • e.g. 1 cycle instructions: ADD, MOV, SETB, NOP
  • e.g. 2 cycle instructions: JMP, JZ
  • 4 cycle instructions: MUL, DIV

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