Stack Mode

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Stack Mode is simply Indirect Mode via register R6, the stack pointer. GI documentation mentions stack mode separately for three reasons:

  • Reads via R6 decrement R6 prior to using its value. No other indirect reads have that behavior.
  • Reading an operand using Stack Mode takes 3 extra cycles.
  • The CP1610 does not officially support SDBD with Stack Mode.

Stack Mode instructions have the same encoding as Indirect Mode and Immediate Mode instructions.