AT89C51 Intel HEX手工结构分析反汇编工具

news2024/11/15 6:48:39

在不查询格式情况下分析确定 Intel HEX 格式

Hex文件内容

:0300000002090BE7
:0C090B00787FE4F6D8FD7581080208F63C
:01091700419E
:1008F60078087C007D007BFF7A0979177E007F01EE
:050906001208D080FE84
:10080000E709F608DFFA8046E709F208DFFA803EDA
:1008100088828C83E709F0A3DFFA8032E309F608C7
:10082000DFFA8078E309F208DFFA807088828C832F
:10083000E309F0A3DFFA806489828A83E0A3F608E3
:10084000DFFA805889828A83E0A3F208DFFA804CBD
:1008500080D280FA80C680D4806980F28033801094
:1008600080A680EA809A80A880DA80E280CA8033FD
:1008700089828A83ECFAE493A3C8C582C8CCC58375
:10088000CCF0A3C8C582C8CCC583CCDFE9DEE78045
:100890000D89828A83E493A3F608DFF9ECFAA9F0C4
:1008A000EDFB2289828A83ECFAE0A3C8C582C8CC1A
:1008B000C583CCF0A3C8C582C8CCC583CCDFEADE33
:1008C000E880DB89828A83E493A3F208DFF980CC95
:1008D00088F0EF60010E4E60C388F0ED2402B4048E
:1008E0000050B9F582EB2402B4040050AF23234535
:0608F00082239008507302
:00000001FF

返回Keil中分析反汇编程序

机器码为02090B

在第一行中

:03000000-02090B-E7

而在第二行090B作为段地址,由此推断第二个位置是存放2Bytes的地址的

:0C-090B-00787FE4F6D8FD7581080208F6-3C

跟进地址090B后发现首个机器码是

C:0x090B 787F MOV R0,#0x7F0850EB - 1

所以现在需要分隔00

:0C-090B-00-787FE4F6D8FD7581080208F6-3C

仔细发现前0C似乎是一个长度大小,转为10进制为12。计算载荷长度为24，由此推断0C是12Bytes。

现在确定了每一段的结构

:<载荷长度>:<段地址>:<类型>:<载荷>:<校验>

def parse_hex_file(hex_file_path):
    """Parse Intel HEX file and return a list of (address, data_bytes) tuples."""
    records = []
    try:
        with open(hex_file_path, 'r') as file:
            for line in file:
                line = line.strip()
                if not line or line[0] != ':':
                    continue
                record_length = int(line[1:3], 16)
                address = int(line[3:7], 16)
                record_type = int(line[7:9], 16)
                data = line[9:9 + record_length * 2]
                checksum = int(line[9 + record_length * 2:11 + record_length * 2], 16)
                if record_type == 0x00:  # Data record
                    data_bytes = bytearray.fromhex(data)
                    records.append((address, data_bytes))
                elif record_type == 0x01:  # End of File record
                    break
    except Exception as e:
        print(f"Error reading file: {e}")
    return records

def hex_to_assembly(data_bytes, start_address):
    """Convert a byte array to C51 assembly code."""
    assembly_code = []
    i = 0
    while i < len(data_bytes):
        opcode = data_bytes[i]
        if opcode == 0x02 and i + 2 < len(data_bytes):  # LJMP addr
            addr = (data_bytes[i + 1] << 8) | data_bytes[i + 2]
            assembly_code.append(f"LJMP {addr:04X}")
            i += 3
        elif opcode == 0x78:  # MOV R0, #data
            data = data_bytes[i + 1]
            assembly_code.append(f"MOV R0, #{data:02X}")
            i += 2
        elif opcode == 0xE4:  # CLR A
            assembly_code.append("CLR A")
            i += 1
        elif opcode == 0xF6:  # MOV @R0, A
            assembly_code.append("MOV @R0, A")
            i += 1
        elif opcode == 0xD8 and i + 2 < len(data_bytes):  # DJNZ R0, addr
            addr = (data_bytes[i + 1] << 8) | data_bytes[i + 2]
            assembly_code.append(f"DJNZ R0, {addr:04X}")
            i += 3
        elif opcode == 0x75 and i + 2 < len(data_bytes):  # MOV Rn, data
            reg = data_bytes[i + 1]
            data = data_bytes[i + 2]
            assembly_code.append(f"MOV R{reg}, #{data:02X}")
            i += 3
        elif opcode == 0x80 and i + 1 < len(data_bytes):  # SJMP addr
            offset = data_bytes[i + 1]
            address = start_address + i + 2 + offset
            assembly_code.append(f"SJMP {address:04X}")
            i += 2
        elif opcode == 0x90 and i + 1 < len(data_bytes):  # NOP
            assembly_code.append("NOP")
            i += 1
        else:
            # Handle other opcodes or unknown opcodes
            assembly_code.append(f"DB {opcode:02X}")  # Unknown opcode
            i += 1

    return assembly_code

def main():
    hex_file_path = "test.hex"  # Path to your .hex file
    data_records = parse_hex_file(hex_file_path)

    for address, data_bytes in data_records:
        print(f"Address: {address:04X}")
        assembly_code = hex_to_assembly(data_bytes, address)
        for line in assembly_code:
            print(f"    {line}")

if __name__ == "__main__":
    main()

通过以上简单的程序可以进行反汇编