FDC37C669-MT SMSC, FDC37C669-MT Datasheet - Page 61

• Manufacturer Part Number: FDC37C669-MT
• Description: IC CTRLR SUPER I/O FLPPY 100TQFP
• Manufacturer: SMSC

Specifications of FDC37C669-MT

• Controller Type: I/O Controller
• Interface: ISA Host
• Voltage - Supply: 4.5 V ~ 5.5 V
• Current - Supply: 25mA
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 100-TQFP, 100-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 638-1008

Format A Track
The Format command allows an entire track to be
formatted. After a pulse from the IDX pin is detected, the
FDC starts writing data on the disk including gaps,
address marks, ID fields, and data fields per the IBM
System 34 or 3740 format (MFM or FM respectively).
The particular values that will be written to the gap and
data field are controlled by the values programmed into
N, SC, GPL, and D which are specified by the host during
the command phase. The data field of the sector is filled
with the data byte specified by D. The ID field for each
sector is supplied by the host; that is, four data bytes per
sector are needed by the FDC for C, H, R, and N
(cylinder,
respectively).
GAP4a
GAP4a
GAP4a
80x
40x
80x
4E
FF
4E
head,
SYNC
SYNC
SYNC
12x
12x
00
00
00
6x
sector
C2
C2
3x
3x
IAM
IAM
IAM
FC
FC
FC
number
GAP1
GAP1
GAP1
50x
26x
50x
4E
FF
4E
SYSTEM 3740 (SINGLE DENSITY) FORMAT
SYSTEM 34 (DOUBLE DENSITY) FORMAT
SYNC
SYNC
SYNC
and
12x
12x
00
6x
00
00
A1
A1
3x
3x
sector
IDAM
IDAM
PERPENDICULAR FORMAT
IDAM
FE
FE
FE
FORMAT FIELDS
C
C
C
Y
L
Y
L
Y
L
size
H
D
H
D
H
D
S
E
C
S
E
C
S
E
C
61
N
O
N
O
N
O
After formatting each sector, the host must send new
values for C, H, R and N to the FDC for the next sector
on the track. The R value (sector number) is the only
value that must be changed by the host after each sector
is formatted. This allows the disk to be formatted with
nonsequential sector addresses (interleaving).
incrementing and formatting continues for the whole track
until the FDC encounters a pulse on the IDX pin again
and it terminates the command.
Table 28 contains typical values for gap fields which are
dependent upon the size of the sector and the number of
sectors on each track. Actual values can vary due to drive
electronics.
C
R
C
C
R
C
C
R
C
GAP2
GAP2
GAP2
22x
11x
41x
4E
FF
4E
SYNC
SYNC
SYNC
12x
12x
00
6x
00
00
A1
A1
3x
3x
DATA
DATA
DATA
FB or
AM
AM
AM
F8
FB
F8
FB
F8
DATA
DATA
DATA
C
R
C
C
R
C
C
R
C
GAP3 GAP 4b
GAP3 GAP 4b
GAP3 GAP 4b
This