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.
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.
All parsing code for Ruby generated by Kaitai Struct depends on the Ruby runtime library. You have to install it before you can parse data.
The Ruby runtime library can be installed from RubyGems:
gem install kaitai-structParse a local file and get structure in memory:
data = Code6502.from_file("path/to/local/file.bin")
Or parse structure from a string of bytes:
bytes = "\x00\x01\x02..."
data = Code6502.new(Kaitai::Struct::Stream.new(bytes))
After that, one can get various attributes from the structure by invoking getter methods like:
data.operations # => get operations
# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
require 'kaitai/struct/struct'
unless Gem::Version.new(Kaitai::Struct::VERSION) >= Gem::Version.new('0.9')
raise "Incompatible Kaitai Struct Ruby API: 0.9 or later is required, but you have #{Kaitai::Struct::VERSION}"
end
##
# 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.
class Code6502 < Kaitai::Struct::Struct
OPCODE = {
0 => :opcode_brk_impl,
1 => :opcode_ora_x_ind,
5 => :opcode_ora_zpg,
6 => :opcode_asl_zpg,
8 => :opcode_php_impl,
9 => :opcode_ora_imm,
10 => :opcode_asl_a,
13 => :opcode_ora_abs,
14 => :opcode_asl_abs,
16 => :opcode_bpl_rel,
17 => :opcode_ora_ind_y,
21 => :opcode_ora_zpg_x,
22 => :opcode_asl_zpg_x,
24 => :opcode_clc_impl,
25 => :opcode_ora_abs_y,
29 => :opcode_ora_abs_x,
30 => :opcode_asl_abs_x,
32 => :opcode_jsr_abs,
33 => :opcode_and_x_ind,
36 => :opcode_bit_zpg,
37 => :opcode_and_zpg,
38 => :opcode_rol_zpg,
40 => :opcode_plp_impl,
41 => :opcode_and_imm,
42 => :opcode_rol_a,
44 => :opcode_bit_abs,
45 => :opcode_and_abs,
46 => :opcode_rol_abs,
48 => :opcode_bmi_rel,
49 => :opcode_and_ind_y,
53 => :opcode_and_zpg_x,
54 => :opcode_rol_zpg_x,
56 => :opcode_sec_impl,
57 => :opcode_and_abs_y,
61 => :opcode_and_abs_x,
62 => :opcode_rol_abs_x,
64 => :opcode_rti_impl,
65 => :opcode_eor_x_ind,
69 => :opcode_eor_zpg,
70 => :opcode_lsr_zpg,
72 => :opcode_pha_impl,
73 => :opcode_eor_imm,
74 => :opcode_lsr_a,
76 => :opcode_jmp_abs,
77 => :opcode_eor_abs,
78 => :opcode_lsr_abs,
80 => :opcode_bvc_rel,
81 => :opcode_eor_ind_y,
85 => :opcode_eor_zpg_x,
86 => :opcode_lsr_zpg_x,
88 => :opcode_cli_impl,
89 => :opcode_eor_abs_y,
93 => :opcode_eor_abs_x,
94 => :opcode_lsr_abs_x,
96 => :opcode_rts_impl,
97 => :opcode_adc_x_ind,
101 => :opcode_adc_zpg,
102 => :opcode_ror_zpg,
104 => :opcode_pla_impl,
105 => :opcode_adc_imm,
106 => :opcode_ror_a,
108 => :opcode_jmp_ind,
109 => :opcode_adc_abs,
110 => :opcode_ror_abs,
112 => :opcode_bvs_rel,
113 => :opcode_adc_ind_y,
117 => :opcode_adc_zpg_x,
118 => :opcode_ror_zpg_x,
120 => :opcode_sei_impl,
121 => :opcode_adc_abs_y,
125 => :opcode_adc_abs_x,
126 => :opcode_ror_abs_x,
129 => :opcode_sta_x_ind,
132 => :opcode_sty_zpg,
133 => :opcode_sta_zpg,
134 => :opcode_stx_zpg,
136 => :opcode_dey_impl,
138 => :opcode_txa_impl,
140 => :opcode_sty_abs,
141 => :opcode_sta_abs,
142 => :opcode_stx_abs,
144 => :opcode_bcc_rel,
145 => :opcode_sta_ind_y,
148 => :opcode_sty_zpg_x,
149 => :opcode_sta_zpg_x,
150 => :opcode_stx_zpg_y,
152 => :opcode_tya_impl,
153 => :opcode_sta_abs_y,
154 => :opcode_txs_impl,
157 => :opcode_sta_abs_x,
160 => :opcode_ldy_imm,
161 => :opcode_lda_x_ind,
162 => :opcode_ldx_imm,
164 => :opcode_ldy_zpg,
165 => :opcode_lda_zpg,
166 => :opcode_ldx_zpg,
168 => :opcode_tay_impl,
169 => :opcode_lda_imm,
170 => :opcode_tax_impl,
172 => :opcode_ldy_abs,
173 => :opcode_lda_abs,
174 => :opcode_ldx_abs,
176 => :opcode_bcs_rel,
177 => :opcode_lda_ind_y,
180 => :opcode_ldy_zpg_x,
181 => :opcode_lda_zpg_x,
182 => :opcode_ldx_zpg_y,
184 => :opcode_clv_impl,
185 => :opcode_lda_abs_y,
186 => :opcode_tsx_impl,
188 => :opcode_ldy_abs_x,
189 => :opcode_lda_abs_x,
190 => :opcode_ldx_abs_y,
192 => :opcode_cpy_imm,
193 => :opcode_cmp_x_ind,
196 => :opcode_cpy_zpg,
197 => :opcode_cmp_zpg,
198 => :opcode_dec_zpg,
200 => :opcode_iny_impl,
201 => :opcode_cmp_imm,
202 => :opcode_dex_impl,
204 => :opcode_cpy_abs,
205 => :opcode_cmp_abs,
206 => :opcode_dec_abs,
208 => :opcode_bne_rel,
209 => :opcode_cmp_ind_y,
213 => :opcode_cmp_zpg_x,
214 => :opcode_dec_zpg_x,
216 => :opcode_cld_impl,
217 => :opcode_cmp_abs_y,
221 => :opcode_cmp_abs_x,
222 => :opcode_dec_abs_x,
224 => :opcode_cpx_imm,
225 => :opcode_sbc_x_ind,
228 => :opcode_cpx_zpg,
229 => :opcode_sbc_zpg,
230 => :opcode_inc_zpg,
232 => :opcode_inx_impl,
233 => :opcode_sbc_imm,
234 => :opcode_nop_impl,
236 => :opcode_cpx_abs,
237 => :opcode_sbc_abs,
238 => :opcode_inc_abs,
240 => :opcode_beq_rel,
241 => :opcode_sbc_ind_y,
245 => :opcode_sbc_zpg_x,
246 => :opcode_inc_zpg_x,
248 => :opcode_sed_impl,
249 => :opcode_sbc_abs_y,
253 => :opcode_sbc_abs_x,
254 => :opcode_inc_abs_x,
}
I__OPCODE = OPCODE.invert
def initialize(_io, _parent = nil, _root = self)
super(_io, _parent, _root)
_read
end
def _read
@operations = []
i = 0
while not @_io.eof?
@operations << Operation.new(@_io, self, @_root)
i += 1
end
self
end
class Operation < Kaitai::Struct::Struct
def initialize(_io, _parent = nil, _root = self)
super(_io, _parent, _root)
_read
end
def _read
@code = Kaitai::Struct::Stream::resolve_enum(Code6502::OPCODE, @_io.read_u1)
case code
when :opcode_bcc_rel
@args = @_io.read_s1
when :opcode_ora_ind_y
@args = @_io.read_u1
when :opcode_lda_ind_y
@args = @_io.read_u1
when :opcode_cpx_zpg
@args = @_io.read_u1
when :opcode_sta_zpg_x
@args = @_io.read_u1
when :opcode_sta_zpg
@args = @_io.read_u1
when :opcode_bcs_rel
@args = @_io.read_s1
when :opcode_ldy_zpg_x
@args = @_io.read_u1
when :opcode_lsr_abs_x
@args = @_io.read_u2le
when :opcode_and_abs_x
@args = @_io.read_u2le
when :opcode_adc_abs
@args = @_io.read_u2le
when :opcode_sta_abs
@args = @_io.read_u2le
when :opcode_bne_rel
@args = @_io.read_s1
when :opcode_lda_imm
@args = @_io.read_u1
when :opcode_adc_imm
@args = @_io.read_u1
when :opcode_lsr_abs
@args = @_io.read_u2le
when :opcode_adc_abs_x
@args = @_io.read_u2le
when :opcode_sta_abs_x
@args = @_io.read_u2le
when :opcode_cpx_imm
@args = @_io.read_u1
when :opcode_jmp_ind
@args = @_io.read_u2le
when :opcode_adc_zpg
@args = @_io.read_u1
when :opcode_eor_imm
@args = @_io.read_u1
when :opcode_eor_abs_x
@args = @_io.read_u2le
when :opcode_sta_x_ind
@args = @_io.read_u1
when :opcode_sbc_imm
@args = @_io.read_u1
when :opcode_cpy_abs
@args = @_io.read_u2le
when :opcode_ldx_abs_y
@args = @_io.read_u2le
when :opcode_adc_zpg_x
@args = @_io.read_u1
when :opcode_bpl_rel
@args = @_io.read_s1
when :opcode_ora_imm
@args = @_io.read_u1
when :opcode_ror_abs_x
@args = @_io.read_u2le
when :opcode_adc_ind_y
@args = @_io.read_u1
when :opcode_eor_ind_y
@args = @_io.read_u1
when :opcode_lda_abs
@args = @_io.read_u2le
when :opcode_bit_zpg
@args = @_io.read_u1
when :opcode_rol_zpg
@args = @_io.read_u1
when :opcode_sty_zpg
@args = @_io.read_u1
when :opcode_jsr_abs
@args = @_io.read_u2le
when :opcode_eor_zpg
@args = @_io.read_u1
when :opcode_eor_abs
@args = @_io.read_u2le
when :opcode_lda_abs_y
@args = @_io.read_u2le
when :opcode_lda_zpg_x
@args = @_io.read_u1
when :opcode_bmi_rel
@args = @_io.read_s1
when :opcode_sty_zpg_x
@args = @_io.read_u1
when :opcode_adc_x_ind
@args = @_io.read_u1
when :opcode_rol_abs_x
@args = @_io.read_u2le
when :opcode_stx_zpg
@args = @_io.read_u1
when :opcode_asl_abs_x
@args = @_io.read_u2le
when :opcode_lsr_zpg_x
@args = @_io.read_u1
when :opcode_ora_zpg_x
@args = @_io.read_u1
when :opcode_adc_abs_y
@args = @_io.read_u2le
when :opcode_ldy_abs
@args = @_io.read_u2le
when :opcode_cmp_abs_x
@args = @_io.read_u2le
when :opcode_lda_abs_x
@args = @_io.read_u2le
when :opcode_bvs_rel
@args = @_io.read_s1
when :opcode_lda_x_ind
@args = @_io.read_u1
when :opcode_cmp_imm
@args = @_io.read_u1
when :opcode_inc_zpg_x
@args = @_io.read_u1
when :opcode_asl_zpg
@args = @_io.read_u1
when :opcode_and_abs_y
@args = @_io.read_u2le
when :opcode_ldx_imm
@args = @_io.read_u1
when :opcode_and_zpg
@args = @_io.read_u1
when :opcode_cpx_abs
@args = @_io.read_u2le
when :opcode_dec_zpg
@args = @_io.read_u1
when :opcode_ror_zpg_x
@args = @_io.read_u1
when :opcode_ldx_zpg
@args = @_io.read_u1
when :opcode_dec_zpg_x
@args = @_io.read_u1
when :opcode_sbc_zpg
@args = @_io.read_u1
when :opcode_cmp_abs
@args = @_io.read_u2le
when :opcode_ror_zpg
@args = @_io.read_u1
when :opcode_inc_abs
@args = @_io.read_u2le
when :opcode_and_x_ind
@args = @_io.read_u1
when :opcode_sbc_abs_x
@args = @_io.read_u2le
when :opcode_asl_abs
@args = @_io.read_u2le
when :opcode_eor_x_ind
@args = @_io.read_u1
when :opcode_ora_abs_x
@args = @_io.read_u2le
when :opcode_ldy_abs_x
@args = @_io.read_u2le
when :opcode_sbc_x_ind
@args = @_io.read_u1
when :opcode_asl_zpg_x
@args = @_io.read_u1
when :opcode_sbc_abs_y
@args = @_io.read_u2le
when :opcode_rol_abs
@args = @_io.read_u2le
when :opcode_lsr_zpg
@args = @_io.read_u1
when :opcode_stx_zpg_y
@args = @_io.read_u1
when :opcode_ora_abs_y
@args = @_io.read_u2le
when :opcode_eor_abs_y
@args = @_io.read_u2le
when :opcode_bit_abs
@args = @_io.read_u2le
when :opcode_ldx_abs
@args = @_io.read_u2le
when :opcode_ldy_imm
@args = @_io.read_u1
when :opcode_jmp_abs
@args = @_io.read_u2le
when :opcode_beq_rel
@args = @_io.read_s1
when :opcode_dec_abs_x
@args = @_io.read_u2le
when :opcode_and_ind_y
@args = @_io.read_u1
when :opcode_and_zpg_x
@args = @_io.read_u1
when :opcode_cmp_zpg_x
@args = @_io.read_u1
when :opcode_eor_zpg_x
@args = @_io.read_u1
when :opcode_sbc_abs
@args = @_io.read_u2le
when :opcode_cmp_abs_y
@args = @_io.read_u2le
when :opcode_sbc_ind_y
@args = @_io.read_u1
when :opcode_cmp_zpg
@args = @_io.read_u1
when :opcode_stx_abs
@args = @_io.read_u2le
when :opcode_sty_abs
@args = @_io.read_u2le
when :opcode_cpy_zpg
@args = @_io.read_u1
when :opcode_dec_abs
@args = @_io.read_u2le
when :opcode_ror_abs
@args = @_io.read_u2le
when :opcode_sta_abs_y
@args = @_io.read_u2le
when :opcode_inc_abs_x
@args = @_io.read_u2le
when :opcode_lda_zpg
@args = @_io.read_u1
when :opcode_cmp_ind_y
@args = @_io.read_u1
when :opcode_cpy_imm
@args = @_io.read_u1
when :opcode_ldx_zpg_y
@args = @_io.read_u1
when :opcode_sbc_zpg_x
@args = @_io.read_u1
when :opcode_ora_x_ind
@args = @_io.read_u1
when :opcode_rol_zpg_x
@args = @_io.read_u1
when :opcode_ora_abs
@args = @_io.read_u2le
when :opcode_sta_ind_y
@args = @_io.read_u1
when :opcode_and_abs
@args = @_io.read_u2le
when :opcode_and_imm
@args = @_io.read_u1
when :opcode_cmp_x_ind
@args = @_io.read_u1
when :opcode_ldy_zpg
@args = @_io.read_u1
when :opcode_inc_zpg
@args = @_io.read_u1
when :opcode_bvc_rel
@args = @_io.read_s1
when :opcode_ora_zpg
@args = @_io.read_u1
end
self
end
attr_reader :code
attr_reader :args
end
attr_reader :operations
end