code_6502: Lua parsing library

This spec can be used to disassemble raw stream of 6502 CPU machine code into individual operations. Each operation includes an opcode and, optionally, an argument. Register arguments are part of the opcode enum.

KS implementation details

License: CC0-1.0

References

This page hosts a formal specification of code_6502 using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Lua source code to parse code_6502

code_6502.lua

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-- This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
--
-- This file is compatible with Lua 5.3

local class = require("class")
require("kaitaistruct")
local enum = require("enum")

-- 
-- This spec can be used to disassemble raw stream of 6502 CPU machine
-- code into individual operations. Each operation includes an opcode
-- and, optionally, an argument. Register arguments are part of the
-- `opcode` enum.
Code6502 = class.class(KaitaiStruct)

Code6502.Opcode = enum.Enum {
  brk_impl = 0,
  ora_x_ind = 1,
  ora_zpg = 5,
  asl_zpg = 6,
  php_impl = 8,
  ora_imm = 9,
  asl_a = 10,
  ora_abs = 13,
  asl_abs = 14,
  bpl_rel = 16,
  ora_ind_y = 17,
  ora_zpg_x = 21,
  asl_zpg_x = 22,
  clc_impl = 24,
  ora_abs_y = 25,
  ora_abs_x = 29,
  asl_abs_x = 30,
  jsr_abs = 32,
  and_x_ind = 33,
  bit_zpg = 36,
  and_zpg = 37,
  rol_zpg = 38,
  plp_impl = 40,
  and_imm = 41,
  rol_a = 42,
  bit_abs = 44,
  and_abs = 45,
  rol_abs = 46,
  bmi_rel = 48,
  and_ind_y = 49,
  and_zpg_x = 53,
  rol_zpg_x = 54,
  sec_impl = 56,
  and_abs_y = 57,
  and_abs_x = 61,
  rol_abs_x = 62,
  rti_impl = 64,
  eor_x_ind = 65,
  eor_zpg = 69,
  lsr_zpg = 70,
  pha_impl = 72,
  eor_imm = 73,
  lsr_a = 74,
  jmp_abs = 76,
  eor_abs = 77,
  lsr_abs = 78,
  bvc_rel = 80,
  eor_ind_y = 81,
  eor_zpg_x = 85,
  lsr_zpg_x = 86,
  cli_impl = 88,
  eor_abs_y = 89,
  eor_abs_x = 93,
  lsr_abs_x = 94,
  rts_impl = 96,
  adc_x_ind = 97,
  adc_zpg = 101,
  ror_zpg = 102,
  pla_impl = 104,
  adc_imm = 105,
  ror_a = 106,
  jmp_ind = 108,
  adc_abs = 109,
  ror_abs = 110,
  bvs_rel = 112,
  adc_ind_y = 113,
  adc_zpg_x = 117,
  ror_zpg_x = 118,
  sei_impl = 120,
  adc_abs_y = 121,
  adc_abs_x = 125,
  ror_abs_x = 126,
  sta_x_ind = 129,
  sty_zpg = 132,
  sta_zpg = 133,
  stx_zpg = 134,
  dey_impl = 136,
  txa_impl = 138,
  sty_abs = 140,
  sta_abs = 141,
  stx_abs = 142,
  bcc_rel = 144,
  sta_ind_y = 145,
  sty_zpg_x = 148,
  sta_zpg_x = 149,
  stx_zpg_y = 150,
  tya_impl = 152,
  sta_abs_y = 153,
  txs_impl = 154,
  sta_abs_x = 157,
  ldy_imm = 160,
  lda_x_ind = 161,
  ldx_imm = 162,
  ldy_zpg = 164,
  lda_zpg = 165,
  ldx_zpg = 166,
  tay_impl = 168,
  lda_imm = 169,
  tax_impl = 170,
  ldy_abs = 172,
  lda_abs = 173,
  ldx_abs = 174,
  bcs_rel = 176,
  lda_ind_y = 177,
  ldy_zpg_x = 180,
  lda_zpg_x = 181,
  ldx_zpg_y = 182,
  clv_impl = 184,
  lda_abs_y = 185,
  tsx_impl = 186,
  ldy_abs_x = 188,
  lda_abs_x = 189,
  ldx_abs_y = 190,
  cpy_imm = 192,
  cmp_x_ind = 193,
  cpy_zpg = 196,
  cmp_zpg = 197,
  dec_zpg = 198,
  iny_impl = 200,
  cmp_imm = 201,
  dex_impl = 202,
  cpy_abs = 204,
  cmp_abs = 205,
  dec_abs = 206,
  bne_rel = 208,
  cmp_ind_y = 209,
  cmp_zpg_x = 213,
  dec_zpg_x = 214,
  cld_impl = 216,
  cmp_abs_y = 217,
  cmp_abs_x = 221,
  dec_abs_x = 222,
  cpx_imm = 224,
  sbc_x_ind = 225,
  cpx_zpg = 228,
  sbc_zpg = 229,
  inc_zpg = 230,
  inx_impl = 232,
  sbc_imm = 233,
  nop_impl = 234,
  cpx_abs = 236,
  sbc_abs = 237,
  inc_abs = 238,
  beq_rel = 240,
  sbc_ind_y = 241,
  sbc_zpg_x = 245,
  inc_zpg_x = 246,
  sed_impl = 248,
  sbc_abs_y = 249,
  sbc_abs_x = 253,
  inc_abs_x = 254,
}

function Code6502:_init(io, parent, root)
  KaitaiStruct._init(self, io)
  self._parent = parent
  self._root = root or self
  self:_read()
end

function Code6502:_read()
  self.operations = {}
  local i = 0
  while not self._io:is_eof() do
    self.operations[i + 1] = Code6502.Operation(self._io, self, self._root)
    i = i + 1
  end
end


Code6502.Operation = class.class(KaitaiStruct)

function Code6502.Operation:_init(io, parent, root)
  KaitaiStruct._init(self, io)
  self._parent = parent
  self._root = root or self
  self:_read()
end

function Code6502.Operation:_read()
  self.code = Code6502.Opcode(self._io:read_u1())
  local _on = self.code
  if _on == Code6502.Opcode.bcc_rel then
    self.args = self._io:read_s1()
  elseif _on == Code6502.Opcode.ora_ind_y then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.lda_ind_y then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.cpx_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.sta_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.sta_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.bcs_rel then
    self.args = self._io:read_s1()
  elseif _on == Code6502.Opcode.ldy_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.lsr_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.and_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.adc_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.sta_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.bne_rel then
    self.args = self._io:read_s1()
  elseif _on == Code6502.Opcode.lda_imm then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.adc_imm then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.lsr_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.adc_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.sta_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.cpx_imm then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.jmp_ind then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.adc_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.eor_imm then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.eor_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.sta_x_ind then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.sbc_imm then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.cpy_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.ldx_abs_y then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.adc_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.bpl_rel then
    self.args = self._io:read_s1()
  elseif _on == Code6502.Opcode.ora_imm then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.ror_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.adc_ind_y then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.eor_ind_y then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.lda_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.bit_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.rol_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.sty_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.jsr_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.eor_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.eor_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.lda_abs_y then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.lda_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.bmi_rel then
    self.args = self._io:read_s1()
  elseif _on == Code6502.Opcode.sty_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.adc_x_ind then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.rol_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.stx_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.asl_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.lsr_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.ora_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.adc_abs_y then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.ldy_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.cmp_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.lda_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.bvs_rel then
    self.args = self._io:read_s1()
  elseif _on == Code6502.Opcode.lda_x_ind then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.cmp_imm then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.inc_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.asl_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.and_abs_y then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.ldx_imm then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.and_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.cpx_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.dec_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.ror_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.ldx_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.dec_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.sbc_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.cmp_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.ror_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.inc_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.and_x_ind then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.sbc_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.asl_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.eor_x_ind then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.ora_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.ldy_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.sbc_x_ind then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.asl_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.sbc_abs_y then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.rol_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.lsr_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.stx_zpg_y then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.ora_abs_y then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.eor_abs_y then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.bit_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.ldx_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.ldy_imm then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.jmp_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.beq_rel then
    self.args = self._io:read_s1()
  elseif _on == Code6502.Opcode.dec_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.and_ind_y then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.and_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.cmp_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.eor_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.sbc_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.cmp_abs_y then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.sbc_ind_y then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.cmp_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.stx_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.sty_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.cpy_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.dec_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.ror_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.sta_abs_y then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.inc_abs_x then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.lda_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.cmp_ind_y then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.cpy_imm then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.ldx_zpg_y then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.sbc_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.ora_x_ind then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.rol_zpg_x then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.ora_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.sta_ind_y then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.and_abs then
    self.args = self._io:read_u2le()
  elseif _on == Code6502.Opcode.and_imm then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.cmp_x_ind then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.ldy_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.inc_zpg then
    self.args = self._io:read_u1()
  elseif _on == Code6502.Opcode.bvc_rel then
    self.args = self._io:read_s1()
  elseif _on == Code6502.Opcode.ora_zpg then
    self.args = self._io:read_u1()
  end
end