brock@arden:~/sysadmin/notes/tryit2$ BPB_SecPerClus=16
brock@arden:~/sysadmin/notes/tryit2$ FirstDataSection=97
brock@arden:~/sysadmin/notes/tryit2$ od -A d -j 26 -N 2 -t d2 issue.txt.direntry.txt
0000026   2545
0000028
brock@arden:~/sysadmin/notes/tryit2$ IssueTxtCluster1=2545
brock@arden:~/sysadmin/notes/tryit2$ od -A d -j 28 -N 4 -t d4 issue.txt.direntry.txt
0000028         103
0000032
brock@arden:~/sysadmin/notes/tryit2$ IssueTxtSize=103
brock@arden:~/sysadmin/notes/tryit2$ FirstDataSector=97
brock@arden:~/sysadmin/notes/tryit2$ function DataSector2Cluster()
> {
>    local result=$(( ( ( $1 - 2 ) * $BPB_SecPerClus ) + $FirstDataSection ))
>    echo "${result}"
> }
brock@arden:~/sysadmin/notes/tryit2$ DataSector2Cluster 2545
40785
brock@arden:~/sysadmin/notes/tryit2$ dd if=boot.img of=issue.txt.cluster skip=40785 bs=512 count=8
8+0 records in
8+0 records out
4096 bytes (4.1 kB) copied, 0.0377886 s, 108 kB/s
brock@arden:~/sysadmin/notes/tryit2$ od -A d -j 14 -N 2 -t d2 boot.BPB.img
0000014      1
0000016
brock@arden:~/sysadmin/notes/tryit2$ BPB_RsvdSecCnt=1
brock@arden:~/sysadmin/notes/tryit2$ od -A d -j 22 -N 2 -t d2 boot.BPB.img
0000022     32
0000024
brock@arden:~/sysadmin/notes/tryit2$ BPB_FATSz16=32
brock@arden:~/sysadmin/notes/tryit2$ FATSz=$BPB_FATSz16
brock@arden:~/sysadmin/notes/tryit2$ dd if=boot.img of=boot.img.fat bs=512 skip=$BPB_RsvdSecCnt count=$FATSz
32+0 records in
32+0 records out
16384 bytes (16 kB) copied, 0.0369708 s, 443 kB/s
brock@arden:~/sysadmin/notes/tryit2$ od -A d -j 0 -N 80 -t d2 boot.img.fat 
0000000     -8     -1     -1      0      0     -1      7      8
0000016      9     10     11     12     13     14     15     16
0000032     17     18     19     20     21     22     23     24
0000048     25     26     27     28     30   4234     31     32
0000064     33     34     35     36     37     38     39     40
0000080
brock@arden:~/sysadmin/notes/tryit2$ od -A d -j $IssueTxtCluster1 -N 1 -t d2 boot.img.fat 
0002545      0
0002546
