use strict;
use warnings;

my $stats;

open my $DEVICE_IN, "<", 'stat.dat'
    or die "Cannot open input device: $!";
$stats = <$DEVICE_IN>;
close $DEVICE_IN;

$stats = pack(
    'b16',
    reverse(
        unpack(
            'B16',
            $stats
        )
    )
);

vec($stats,  2, 1)  = 0;    # Reset bit 2
vec($stats,  6, 1)  = 1;    # Set bit 6
vec($stats, 10, 1) ^= 1;    # Toggle bit 10 

$stats = pack(
    'b16',
    reverse(
        unpack(
            'B16',
            $stats
        )
    )
);

open my $DEVICE_OUT, ">", 'newstat.dat'
    or die "Cannot open output device: $!";
print $DEVICE_OUT $stats;
close $DEVICE_OUT;

##</code><code>##

C:\Users\Bill\forums\monks>xxd stat.dat
00000000: f531                                     .1

C:\Users\Bill\forums\monks>xxd newstat.dat
00000000: d711                                     ..

C:\Users\Bill\forums\monks>