Advanced I/O Controller with Motherboard GLUE Logic
Datasheet
FORMAT FIELDS
SYSTEM 34 (DOUBLE DENSITY) FORMAT
DATA
AM
GAP4a SYNC
IAM
GAP1 SYNC IDAM
C
Y
L
H
D
S
E
C
N
O
C
R
C
GAP2 SYNC
C
R
C
80x
4E
12x
00
50x
4E
12x
00
22x
4E
12x
00
DATA
GAP3 GAP 4b
3x FC
C2
3x FE
A1
3x FB
A1 F8
SYSTEM 3740 (SINGLE DENSITY) FORMAT
DATA
AM
GAP4a SYNC
IAM
FC
GAP1 SYNC IDAM
C
Y
L
H
D
S
E
C
N
O
C
R
C
GAP2 SYNC
C
R
C
40x
FF
6x
00
26x
FF
6x
00
11x
FF
6x
00
DATA
DATA
GAP3 GAP 4b
FE
FB or
F8
PERPENDICULAR FORMAT
DATA
AM
GAP4a SYNC
IAM
GAP1 SYNC IDAM
C
Y
L
H
D
S
E
C
N
O
C
R
C
GAP2 SYNC
C
R
C
80x
4E
12x
00
50x
4E
12x
00
41x
4E
12x
00
GAP3 GAP 4b
3x FC
C2
3x FE
A1
3x FB
A1 F8
Table 6.24 - Typical Values for Formatting
FORMAT SECTOR SIZE
N
SC GPL1 GPL2
128
128
512
00 12
00 10
02 08
03 04
04 02
05 01
...
07
10
18
46
C8
C8
09
19
30
87
FF
FF
FM
1024
2048
4096
...
5.25” Drives
3.5” Drives
256
01 12
01 10
02 09
03 04
04 02
05 01
...
0
1
2
1
2
3
0A
20
2A
80
C8
C8
0C
32
50
F0
FF
FF
256
512*
1024
2048
4096
...
MFM
128
0F
09
05
0F
09
05
07
0F
1B
0E
1B
35
1B
2A
3A
36
54
74
FM
256
512
256
MFM
512**
1024
GPL1 = suggested GPL values in Read and Write commands to avoid splice point between data field and
ID field of contiguous sections.
GPL2 = suggested GPL value in Format A Track command.
*PC/AT values (typical)
**PS/2 values (typical). Applies with 1.0 MB and 2.0 MB drives.
Note: All values except sector size are in hex.
Revision 1.8 SMSC/Non-SMSC Register Sets (02-24-05)
70
SMSC LPC47M182
DATASHEET
SMSC [ SMSC CORPORATION ]
