User`s guide
1541 RELATIVE FILE FORMAT
BYTE
DEFINITION
DATA BLOCK
0,
1
Track and sector
of
next data block.
2-255
254 bytes
of
data. Empty records contain $FF
(all binary ones)
in
the first byte followed by $00
(binary all zeros) to the end
of
the record. Partially
filled records are padded with nulls ($00).
SIDE SECTOR BLOCK
0-1
Track and sector
of
next side sector block.
2
Side sector number (0-5)
3
Record length
4-5
Track and sector
of
first side sector (number 0)
6-7
Track and sector
of
second side sector (number
1)
8-9
Track and sector
of
third side sector (number 2)
10
-
11
Track and sector
of
fourth side sector (number 3)
12-13
Track and sector
of
fifth side sector (number 4)
14-15
Track and sector
of
sixth side sector (number 5)
16-255
Track and sector pointers to
120
data blocks.
90
BYTE
0, 1
2-31
34-63
66-
95
98-127
130-159
162-191
194-223
226-255
1541 DIRECTORY FILE FORMAT
Track 18, Sector 1.
DEFINITION
Track and sector
of
next directory block.
File entry 1 *
File entry 2*
File entry 3 *
File entry 4*
File entry
5 *
File entry 6*
File entry 7*
File entry 8*
*STRUCTURE OF EACH INDIVIDUAL DIRECTORY ENTRY
BYTE CONTENTS
DEFINITION
0
128
File type OR 'ed with $80 to indicate properly closed file.
+
(if
OR'ed
with
$CO
instead,
file
is
locked.)
type
TYPES: 0 = DELeted
1 = SEQuential
2 =
PROGram
3
=USER
4 = RELative
1-2
Track and sector
of
first data block.
3-18
File name padded with shifted spaces.
19-20
Relative file only: track and sector
of
first side
sector block.
21
Relative file only: Record length.
22-25
Unused.
26-
27
Track and sector
of
replacement
file
puring an
@SA VE or @OPEN.
28-29
Number
of
blocks
in
file
: stored
as
a two-byte integer,
in
low byte, high byte order.
91