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SYSTEM DESCRIPTION
24. 1 -- Diskette
St~ucture
Bytes
-----
$0-7
$8-9
$A-B
$C-D
$E-F
Size
8
2
2
2
2
Contents
File name
Suffix
PSN of first cluster
Attributes
Zeroes
The
att-ribute
field
o~
a
directo-ry
entry
has
the
follo~ing
format:
F
E
o
c
B
A
9
8
7
6
4
3
2
1
o
-----------------------------------------------------------
<--------
Not
Used
(=0)
-------~
File
format (O=user-defined,
2=memcry-imag
e;
3=binary T'"ecord,
5=ASCI
I
record}
7=ASClI-converted-
binarq record)
Non-compressed space bit
.Contiguous allocation bit
S\lstem file bit
Delete protection bit
Write protection bit
Associated
with
each
diT'ectory
entry is an eight-bit
numbeT'1
the directory entry number
(DEN),
which
is
a
runction
of
the
phqsical location of the entry within the directorq.
The DEN-is not found anywhere in
the
directory.
It
is
a
calculated
~uantity
and is interpreted as follows:
7
6
5
4
3
24. 1. 5
Bootb loc k
2
1
o
Position within sector
(0-7)
Physical sector number
($3-$16)
The
Bootblock is
a small
loader program that
is
brought
into memorq along
with
the
next
physical
sector
by
the
diskette
contralle~
during system initialization.
The second
/
Page
24-06
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