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Stack Relative Indirect Indexed, Y Addressing: Difference between revisions

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They are all two bytes long.
They are all two bytes long.
The indirect address lives on the [[stack]] at sum of the [[stack pointer]] and the 8-bit operand.


The effective address is generated by concatenating the [[data bank register]] to the indirect address, and then adding the [[Y index register]] to the 24-bit sum.
The effective address is generated by concatenating the [[data bank register]] to the indirect address, and then adding the [[Y index register]] to the 24-bit sum.

Revision as of 05:21, 24 July 2024

Stack Relative Indirect Indexed, Y Addressing is supported by eight instructions:

  • ADC (opcode 73)
  • AND (opcode 33)
  • CMP (opcode D3)
  • EOR (opcode 53)
  • LDA (opcode B3)
  • ORA (opcode 13)
  • SBC (opcode F3)
  • STA (opcode 93)

They are all two bytes long.

The indirect address lives on the stack at sum of the stack pointer and the 8-bit operand.

The effective address is generated by concatenating the data bank register to the indirect address, and then adding the Y index register to the 24-bit sum.

Syntax

LDA (sr, S), Y

See Also

References