https://forums.servethehome.com/index.php?threads/fun-with-an-md1200-md1220-sc200-sc220.27487

diavoli.py

INPUT_FILENAME = "input.txt"
OUTPUT_FILENAME = "out.bin"
OUTPUT_DUMP_FILENAME = "out.txt"
MAGIC_OFFSET = 0x133
CHECKSUM_OFFSET = 0x143

def print_header():
    print('''

      _____ _____     __      ______  _      _____
     |  __ \_   _|   /\ \    / / __ \| |    |_   _|
     | |  | || |    /  \ \  / / |  | | |      | |
     | |  | || |   / /\ \ \/ /| |  | | |      | |
     | |__| || |_ / ____ \  / | |__| | |____ _| |_
     |_____/_____/_/    \_\/   \____/|______|_____|


    ''')


def load_file():
    hex_contents = ""
    with open(INPUT_FILENAME, 'r') as f:
        lines = f.readlines()
        for line in lines:
            chunks = line.split(' ')
            begin = 1
            for i in range(begin, begin + 16):
                hex_contents += chunks[i]
    return bytearray(bytes.fromhex(hex_contents))

def write_file(data):
    with open(OUTPUT_FILENAME, 'wb') as f:
        f.write(data)

def print_bytearray(byte_array, outfile=None):
    # Define the width of each line
    line_width = 16

    # Iterate over the bytearray
    for i in range(0, len(byte_array), line_width):
        # Get the current line
        line = byte_array[i:i + line_width]

        # Format the offset
        offset = format(i, '08X')

        # Format the bytes
        hex_bytes = ' '.join(f'{byte:02x}' for byte in line)
        ascii_chars = ''.join(chr(byte) if 32 <= byte < 127 and byte != 0x20 else '.' for byte in line)

        # Print the formatted output
        line = f'{offset}: {hex_bytes.ljust(line_width * 3)} {ascii_chars}'
        if outfile:
            outfile.write(line + '\n')
        else:
            print(line)



def get_magic(index):
    magics = {
        1: ('MD-DEVILS', 0xDA),
        2: ('HOGS_SAS', 0xE8),
        3: ('SC-SURLY', 0xFD),
        4: ('EQ-PIRATES', 0x84),
    }
    index = int(index)
    if index not in magics:
        raise ValueError
    return magics[index]


def main():
    print_header()
    print(f'Loading from {INPUT_FILENAME}')
    f = load_file()
    print(f'Loaded {len(f)} bytes')

    print('Chassis types:')
    print('\t1) MD12XX')
    print('\t2) MD32XX')
    print('\t3) SC2XX')
    print('\t4) PS6200')
    print('Select desired chassis type: ', end='')
    chassis_type = get_magic(input())

    magic = chassis_type[0]
    checksum = chassis_type[1]
    # Clear our magic
    for i in range(MAGIC_OFFSET, CHECKSUM_OFFSET):
        f[i] = 0x00
    # Write magic
    for i, b in enumerate(magic.encode('utf-8')):
        f[MAGIC_OFFSET + i] = b
    # Set the checksum
        f[CHECKSUM_OFFSET] = checksum

    print('Modified file:')
    print_bytearray(f)
    with open(OUTPUT_DUMP_FILENAME, 'w') as outfile:
        print_bytearray(f, outfile)
    print()

    write_file(f)
    print('\n\n\n')
    print('Wrote:')
    print(f'\t1. {OUTPUT_FILENAME}')
    print(f'\t2. {OUTPUT_DUMP_FILENAME}')
    print()
    print('You can compare out.txt to your input.txt to see the differences, then use fru_download and xmodem flash out.bin')
    print('Thank you for using diavoli!')



if __name__ == '__main__':
    main()