LPC47M112_07 SMSC [SMSC Corporation], LPC47M112_07 Datasheet - Page 50

• Manufacturer Part Number: LPC47M112_07
• Description: Enhanced Super I/O Controller with LPC Interface
• Manufacturer: SMSC [SMSC Corporation]

Enhanced Super I/O Controller with LPC Interface
Datasheet
SC is returned if the last command that was issued was the Format command. EOT is returned if the last command was
a Read or Write.
Note: These bits are used internally only. They are not reflected in the Drive Select pins. It is the user's responsibility to
maintain correspondence between these bits and the Drive Select pins (DOR).
DATA TRANSFER COMMANDS
All of the Read Data, Write Data and Verify type commands use the same parameter bytes and return the same results
information, the only difference being the coding of bits 0-4 in the first byte.
An implied seek will be executed if the feature was enabled by the Configure command. This seek is completely
transparent to the user. The Drive Busy bit for the drive will go active in the Main Status Register during the seek portion
of the command. If the seek portion fails, it is reflected in the results status normally returned for a Read/Write Data
command. Status Register 0 (ST0) would contain the error code and C would contain the cylinder on which the seek
failed.
Read Data
A set of nine (9) bytes is required to place the FDC in the Read Data Mode. After the Read Data command has been
issued, the FDC loads the head (if it is in the unloaded state), waits the specified head settling time (defined in the
Specify command), and begins reading ID Address Marks and ID fields. When the sector address read off the diskette
matches with the sector address specified in the command, the FDC reads the sector's data field and transfers the data
to the FIFO.
After completion of the read operation from the current sector, the sector address is incremented by one and the data
from the next logical sector is read and output via the FIFO. This continuous read function is called "Multi-Sector Read
Operation". Upon receipt of the TC cycle, or an implied TC (FIFO overrun/underrun), the FDC stops sending data but
will continue to read data from the current sector, check the CRC bytes, and at the end of the sector, terminate the Read
Data Command.
N determines the number of bytes per sector (see Table 18). If N is set to zero, the sector size is set to 128. The DTL
value determines the number of bytes to be transferred. If DTL is less than 128, the FDC transfers the specified number
of bytes to the host. For reads, it continues to read the entire 128-byte sector and checks for CRC errors. For writes, it
completes the 128-byte sector by filling in zeros. If N is not set to 00 Hex, DTL should be set to FF Hex and has no
impact on the number of bytes transferred.
SMSC DS – LPC47M112
Command
Command
Result
Command
Result
PHASE
PHASE
PHASE
R/W
R/W
R/W
W
W
W
R
R
D7
OW
D7
LOCK
0
D7
0
D6
───── Invalid Codes ─────
D6
0
0
─────── ST0 ───────
D6
DATASHEET
D5
0
0
PERPENDICULAR MODE
D5
D3
0
DATA BUS
INVALID CODES
D5
D4
0
0
D2
D4
1
DATA BUS
DATA BUS
Page 50
LOCK
D3
LOCK
D3
D1
D4
0
1
D2
D2
D0
0
D3
0
0
D1
GAP
D1
1
D2
0
1
D0
D1
WGATE
0
0
Invalid Command Codes
(NoOp - FDC goes into Stand-
by State)
ST0 = 80H
D0
0
D0
0
0
REMARKS
Command Codes
Command Codes
REMARKS
REMARKS
Rev. 02-16-07