82077AA Datasheet, PDF (28/62 Pages) Intel Corporation – CHMOS SINGLE-CHIP FLOPPY DISK CONTROLLER

82077AA
5 25 Drive
MFM
Table 5-8 Typical Values for Formatting
Sector Size
N
SC
256
256
512
1024
2048
4096
01
12
01
10
02
09
03
04
04
02
05
01
GPL1
0A
20
2A
80
C8
C8
GPL2
0C
32
50
F0
FF
FF
3 5 Drive
MFM
256
512
1024
1
0F
0E
36
2
09
1B
54
3
05
35
74
GPL1 e suggested GPL values in read and write commands to avoid splice point between data field and ID field of contigu-
ous sections
GPL2 e suggested GPL value in FORMAT 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
5 1 7 1 Format Fields
GAP 4a SYNC ^IAM GAP 1 SYNC ^IDAM C _H S _N C GAP 2 SYNC ^{DATA AM}
80x
4E
12x _3x
50x
00 _C2 ^FC 4E
12x
00
3x
A1
FE
Y
L
D
E
C
O
R
C
22x
4E
12x _{3x FB}
00 _{A1 F8}
Figure 5-1 System 34 Format Double Density
DATA
C
R GAP 3 GAP 4b
C
GAP 4a SYNC ^IAM GAP 1 SYNC ^IDAM C _H S _N C GAP 2 SYNC ^{DATA AM}
80x
4E
12x
00
3x
C2
FC
50x
4E
12x
00
3x
A1
FE
Y
L
D
E
C
O
R
C
41x
4E
12x _{3x FB}
00 _{A1 F8}
Figure 5-2 Perpendicular Format
DATA
C
R GAP 3 GAP 4b
C
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