mirror of
https://github.com/portapack-mayhem/mayhem-firmware.git
synced 2024-12-15 20:50:28 +00:00
58 lines
1.4 KiB
Python
58 lines
1.4 KiB
Python
|
#!/usr/bin/env python3
|
||
|
|
||
|
#
|
||
|
# Copyright (C) 2024 Mark Thompson
|
||
|
#
|
||
|
# This file is part of PortaPack.
|
||
|
#
|
||
|
# This program is free software; you can redistribute it and/or modify
|
||
|
# it under the terms of the GNU General Public License as published by
|
||
|
# the Free Software Foundation; either version 2, or (at your option)
|
||
|
# any later version.
|
||
|
#
|
||
|
# This program is distributed in the hope that it will be useful,
|
||
|
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
# GNU General Public License for more details.
|
||
|
#
|
||
|
# You should have received a copy of the GNU General Public License
|
||
|
# along with this program; see the file COPYING. If not, write to
|
||
|
# the Free Software Foundation, Inc., 51 Franklin Street,
|
||
|
# Boston, MA 02110-1301, USA.
|
||
|
#
|
||
|
|
||
|
import sys
|
||
|
import struct
|
||
|
|
||
|
usage_message = """
|
||
|
PortaPack ROM image checksum checker
|
||
|
|
||
|
Usage: <command> <input-file>
|
||
|
"""
|
||
|
|
||
|
def read_image(path):
|
||
|
f = open(path, 'rb')
|
||
|
data = f.read()
|
||
|
f.close()
|
||
|
return data
|
||
|
|
||
|
def write_image(data, path):
|
||
|
f = open(path, 'wb')
|
||
|
f.write(data)
|
||
|
f.close()
|
||
|
|
||
|
if len(sys.argv) != 2:
|
||
|
print(usage_message)
|
||
|
sys.exit(-1)
|
||
|
|
||
|
image = read_image(sys.argv[1])
|
||
|
image = bytearray(image)
|
||
|
|
||
|
# simple "add up the words" checksum:
|
||
|
checksum = 0
|
||
|
for i in range(0, len(image), 4):
|
||
|
checksum += (image[i] + (image[i + 1] << 8) + (image[i + 2] << 16) + (image[i + 3] << 24))
|
||
|
|
||
|
checksum &= 0xFFFFFFFF
|
||
|
print ("Simple checksum =", checksum)
|