FDC37B77X SMSC Corporation, FDC37B77X Datasheet - Page 148

• Manufacturer Part Number: FDC37B77X
• Description: ENHANCED SUPER I/O CONTROLLER WITH WAKE UP FEATURES
• Manufacturer: SMSC Corporation

FDD Option
Register
Default = 0x00
on Vcc POR or
Reset_Drv
FDD Type Register
Default = 0xFF
on Vcc POR or
Reset_Drv
FDD0
Default = 0x00
on Vcc POR or
Reset_Drv
FDD1
Table 59 - Floppy Disk Controller, Logical Device 0 [Logical Device Number = 0x00]
NAME
REG INDEX
0xF1 R/W
0xF2 R/W
0xF4 R/W
0xF5 R/W
0xF3 R
Bit[0] Forced Write Protect 0
= 0
= 1
Bit[1] Reserved
Bits[3:2] Density Select
= 00
= 01
= 10
= 11
Bit[7:4] Reserved.
nWRTPRT (to the FDC Core) = (nDS0 AND FORCE
WRTPRT) OR nWRTPRT (from the FDD Interface)
Note: Boot floppy is always drive 0.
Note: the Force Write Protect 0 bit also applies to the
Bits[1:0] Floppy Drive A Type
Bits[3:2] Floppy Drive B Type
Bits[5:4] Reserved (could be used to store Floppy
Bits[7:6] Reserved (could be used to store Floppy
Note: The FDC37B77x 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
Parallel Port FDC.
the drive has been selected.
Inactive (default)
FDD nWRTPRT input is forced active when
=0 Use Precompensation
=1 No Precompensation
Normal (default)
Normal (reserved for users)
1 (forced to logic "1")
0 (forced to logic "0")
Drive C type)
Drive D type)
Read as 0 (read only)
Read as 0 (read only)
Precompensation Disable PTS
Read as 0 (read only)
148
DEFINITION
STATE
C
C
C
C
C