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Stack Relative Addressing

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Stack Relative Addressing is supported by eight instructions:

  • ADC (opcode 63)
  • AND (opcode 23)
  • CMP (opcode C3)
  • EOR (opcode 43)
  • LDA (opcode A3)
  • ORA (opcode 03)
  • SBC (opcode E3)
  • STA (opcode 83)

They are all two bytes long. The effective addresses generated by stack relative addressing will always be in bank 0.[3] The effective address is the sum of the stack pointer and the 8-bit operand byte.

Syntax

LDA sr, S

There is no long version of this addressing mode.

See Also

References

  1. Eyes & Lichty, page 418
  2. section 3.5.23 of 65c816 datasheet, https://westerndesigncenter.com/wdc/documentation/w65c816s.pdf
  3. lbid, section 3.2
  4. Clark, Bruce. http://www.6502.org/tutorials/65c816opcodes.html#5.20