VT82C686B
Index F6 – Floppy Controller Configuration..................RW
Index F8 – Floppy Drive Control .................................... RW
........................................ always reads 0
Floppy Drive On Parallel Port
(see table below)
(see table below)
(see table below)
(see table below)
7-6 Reserved
5
7-6 Floppy Drive 3
5-4 Floppy Drive 2
3-2 Floppy Drive 1
1-0 Floppy Drive 0
0
1
Parallel Port (SPP) Mode.......................default
FDC Mode
This bit is used in notebook applications to allow
attachment of an external floppy drive using the
parallel port I/O connector:
DRVEN1 DRVEN0
00
01
10
11
DRATE0
DRATE0
DENSEL
DRATE1
SPP Mode Pin Type
FDC Mode Pin Type
DRATE0 DENSEL#
DRATE1 DRATE0
STROBE#
I/O
-
n/a
PD0
PD1
PD2
PD3
PD4
PD5
PD6
PD7
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
INDEX#
TRK00#
WRTPRT#
RDATA#
I
I
I
I
I
n/a
n/a
n/a
DSKCHG#
-
-
-
ACK#
BUSY
PE
SLCT
AUTOFD#
ERROR#
PINIT#
SLCTIN#
I
I
I
DS1#
O
O
O
O
O
O
O
O
MTR1#
WDATA#
WGATE#
DRVEN0
HDSEL#
DIR#
I
I/O
I
I/O
I/O
STEP#
4
3-Mode FDD
0
Disable ...................................................default
1
Enable
........................................ always reads 0
Four Floppy Drive Option
3
2
Reserved
0
Internal 2-Drive Decoder .......................default
1
External 4-Drive Decoder
1
0
FDC DMA Non-Burst
0
Burst .....................................................default
1
Non-Burst
FDC Swap
0
Disable ...................................................default
1
Enable
Revision 1.71 June 9, 2000
-47-
Register Descriptions - Super-I/O I/O Ports
ETC [ ETC ]
