82091AA Datasheet, PDF (149/204 Pages) Intel Corporation – ADVANCED INTEGRATED PERIPHERAL (AIP)

82091AA
Table 29 Result Phase
MT
Head
Final Sector Transferred to Host
ID Information at Result Phase
C
H
R
N
0
Less than EOT
NC
NC
R^a1
NC
0
Equal to EOT
C^a1
NC
01
NC
1
Less than EOT
NC
NC
R^a1
NC
Equal to EOT
C^a1
NC
01
NC
0
Less than EOT
NC
NC
R^a1
NC
1
Equal to EOT
NC
LSB
01
NC
1
Less than EOT
NC
NC
R^a1
NC
Equal to EOT
C^a1
LSB
01
NC
NOTE
1 NCeno change the same value as the one at the beginning of command execution
2 LSBeleast significant bit the LSB of H is complemented
8 5 2 3 Read Track
This command is similar to the READ DATA Com-
mand except that the entire data field is read contin-
uously from each of the sectors of a track Immedi-
ately after encountering a pulse on the INDEX pin
the FDC starts to read all data fields on the track as
continuous blocks of data without regard to logical
sector numbers If the FDC finds an error in the ID or
DATA CRC check bytes it continues to read data
from the track and sets the appropriate error bits at
the end of the command The FDC compares the ID
information read from each sector with the specified
value in the command and sets the ND flag to 1 in
Status Register 1 if there is no comparison Multi-
track or skip operations are not allowed with this
command The MT and SK bits (Bits D7 and D5 of
the first command byte respectively) should always
be set to 0
This command terminates when the EOT specified
number of sectors have been read If the FDC does
not find an ID address mark on the diskette after the
second occurrence of a pulse on the INDEX pin
then it sets the IC code in Status Register 0 to 01
(Abnormal termination) sets the MA bit in Status
Register 1 to 1 and terminates the command
8 5 2 4 Write Data
After the WRITE DATA Command has been issued
the FDC loads the head (if it is in the unloaded
state) waits the specified head load time if unloaded
(defined in the SPECIFY Command) and begins
reading ID fields When the sector address read
from the diskette matches the sector address speci-
fied in the command the FDC reads the data from
the host via the FIFO and writes it to the sector’s
data field
After writing data into the current sector the FDC
computes the CRC value and writes it into the CRC
field at the end of the sector transfer The sector
number stored in R is incremented by one and the
FDC continues writing to the next data field The
FDC continues this multi-sector write operation If a
terminal count signal is received or a FIFO over un-
der run occurs while a data field is being written the
remainder of the data field is filled with zeros
The FDC reads the ID field of each sector and
checks the CRC bytes If the FDC detects a CRC
error in one of the ID fields it sets the IC code in
Status Register 0 to 01 (Abnormal termination) sets
the DE bit of Status Register 1 to 1 and terminates
the WRITE DATA Command
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