decode.pl

#!/usr/bin/perl
use warnings;
use strict;
use List::Util qw(reduce);

sub pkt2 {
    my ($id, $w, $r) = @_;

    my $bw = pack("H*" x 41, $w);
    my @v = unpack("n" x 20 . "C", $bw);
    my @b = unpack("C" x 41, $bw);
#    printf("%d\n", ((reduce { $a + $b} @b[4..39]) - $b[40])%256);
    printf "%s\n", join(',', (map {sprintf("%5d", $_)} @v[0..1]), (map {sprintf("%5d", $_ - 2000)} @v[2..19]), sprintf("%d", $v[20]) );
}

my $lid = 0;
my ($rpkt, $wpkt);

sub pkt {
    my ($id, $tx, $rx) = @_;
    return if $id eq "";
    if($id != $lid) {
        pkt2($lid, $wpkt, $rpkt);
        ($rpkt, $wpkt, $lid)=("", "", $id);
    }
    $wpkt.=$tx;
    $rpkt.=$rx;
}
$/ = "\r\n";
<>;
while(<>) {
    chomp;
    s/0x//g;
    my ($tme,$id,$tx,$rx) = split /,/;
    pkt($id,$tx,$rx);
}