SCSI2SD/tools/hexChecksum.pl
2015-05-04 20:21:28 +10:00

49 lines
1.5 KiB
Perl

#!/usr/bin/perl -w
# Copyright (C) 2014 Michael McMaster <michael@codesrc.com>
#
# This file is part of SCSI2SD.
#
# SCSI2SD 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 3 of the License, or
# (at your option) any later version.
#
# SCSI2SD 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 SCSI2SD. If not, see <http://www.gnu.org/licenses/>.
# Calculates the checksum of all flash data within Cypress PSoC 5lp .hex files
# Allows fixing the checksum after manual hacking of the hex files
use strict;
use warnings;
my $sum = 0;
while (my $line = <>)
{
$line =~ s/[\n\r]//g;
if ($line =~ /^:40[0-9A-F]{4}00(.+)[0-9A-F]{2}$/)
{
my $binrec = pack('H*', $1);
$sum += unpack('%16C*', $binrec);
}
elsif ($line eq ":0200000490303A")
{
my $checksumRec = sprintf(":02000000%04X", ($sum & 0xffff));
# create checksum of checksum record.
my $sum2 = unpack('%8C*', pack('H*', substr($checksumRec, 1)));
$checksumRec .= sprintf('%2X', (~$sum2 + 1) & 0xFF);
print("Flash data checksum record = $checksumRec\n");
print("(Replace line below ':0200000490303A'\n");
exit;
}
}