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6502-opcodes/README.md
Mark Canlas 00575f46f7 simplify iterators
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6502-opcodes

Addressing modes

  • Immediate: a value literal
  • ZeroPage: argument is an 8-bit address to the zero page
  • ZeroPageX: argument is an 8-bit address to the zero page, incremented by X without carry
  • ZeroPageY: argument is an 8-bit address to the zero page, incremented by Y without carry
  • Absolute: argument is an 16-bit address
  • AbsoluteX: argument is an 16-bit address, incremented by X with carry
  • AbsoluteY: argument is an 16-bit address, incremented by Y with carry
  • Indirect: argument an address (A); the effective value is an address (B) stored at that address (A); used only by Jump
  • IndirectX: argument is an 8-bit address; find a value at this address incremented by the value X
  • IndirectY: argument is an 8-bit address; find a value at this address; increment the value by Y

TODO

  • add mapping support
  • postfix operations to accumulator values
  • loops