lpc47s457-ns Standard Microsystems Corp., lpc47s457-ns Datasheet - Page 209

• Manufacturer Part Number: lpc47s457-ns
• Description: Advanced I/o With X-bus Interface
• Manufacturer: Standard Microsystems Corp.

SMSC LPC47S45x
FDD Option Register
Default = 0x00
on VCC POR,
VTR POR and
PCI RESET
FDD Type Register
Default = 0xFF
on VCC POR,
VTR POR and
PCI RESET
FDD0
Default = 0x00
on VCC POR,
VTR POR and
PCI RESET
FDD1
NAME
Table 87 − Floppy Disk Controller, Logical Device 0 [Logical Device Number = 0x00]
REG INDEX
(R/W)
(R/W)
(R/W)
(R/W)
0xF1
0xF2
0xF3
0xF4
0xF5
(R)
Bit[0] Forced Write Protect
= 0
= 1
Bit[1] Reserved
Bits[3:2] Density Select
= 00
= 01
= 10
= 11
Bit[7:4] Reserved.
nWRTPRT (to the FDC Core) = WP (FDC SRA Register, Bit 1)
Note: Floppy Write Protect bit is in the Device Disable register.
Note: Boot floppy is always drive 0.
Note: the Force Write Protect bits also apply to the Parallel
Bits[1:0] Floppy Drive A Type
Bits[3:2] Floppy Drive B Type
Bits[5:4] Reserved (could be used to store Floppy Drive C type)
Bits[7:6] Reserved (could be used to store Floppy Drive D type)
Note: The LPC47S45x supports two floppy drives
Reserved, Read as 0 (read only)
Bits[1:0] Drive Type Select: DT1, DT0
Bits[2]
Bits[4:3] Data Rate Table Select: DRT1, DRT0
Bits[5]
Bits[6]
Bits[7]
Refer to definition and default for 0xF4
DATASHEET
the drives has been selected.
= (Floppy Write Protect) OR nWRTPRT(from the FDD
Interface) OR (nDS0 AND Force Write Protect ) OR (nDS1
AND Force Write Protect ).
Inactive (default)
FDD nWRTPRT input is forced active when
=0 Use Precompensation
=1 No Precompensation
Read as 0 (read only)
Read as 0 (read only)
Precompensation Disable PTS
Read as 0 (read only)
Page 209 of 259
Normal (default)
Normal (reserved for users)
1 (forced to logic "1")
0 (forced to logic "0")
Port FDC.
DEFINITION
either of
Rev. 08-10-09
STATE
C
C
C
C
C