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Direct Page Addressing

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Direct Page Addressing is an addressing mode that is supported by the 65c816 and SPC700. The effective addresses generated by it are always in bank 0.[4]

The operand specifies which byte of the direct page to access.

Syntax

LDA dp

Supported by 24 instructions on the '816:

  • ADC (opcode 65)
  • SBC (opcode E5)
  • EOR (opcode 45)
  • ASL (opcode 06)
  • LSR (opcode 46)
  • INC (opcode E6)
  • DEC (opcode C6)
  • BIT (opcode 24)
  • CMP (opcode C5)
  • CPX (opcode E4)
  • CPY (opcode C4)
  • ORA (opcode 05)
  • AND (opcode 25)
  • LDA (opcode A5)
  • LDX (opcode A6)
  • LDY (opcode A4)
  • ROL (opcode 26)
  • ROR (opcode 66)
  • STA (opcode 85)
  • STX (opcode 86)
  • STY (opcode 84)
  • STZ (opcode 64)
  • TRB (opcode 14)
  • TSB (opcode 04)

See Also

References

  1. Eyes & Lichty, page 389: https://archive.org/details/0893037893ProgrammingThe65816/page/389
  2. lbid, page 114: https://archive.org/details/0893037893ProgrammingThe65816/page/n140
  3. section 3.5.17 of 65c816 datasheet, https://westerndesigncenter.com/wdc/documentation/w65c816s.pdf
  4. lbid, section 3.3