W83977A Winbond Electronics Corp America, W83977A Datasheet - Page 22

• Manufacturer Part Number: W83977A
• Description: Winbond I/O
• Manufacturer: Winbond Electronics Corp America

1.5 Multi-Mode Parallel Port, continued
1.6 FDC Interface
PD7
DRVDEN0
DRVDEN1
GP10
(IRQIN1)
P12
DIR
DSA
DSB
HEAD
MOB
SCI
WE
WD
STEP
SYMBOL
SYMBOL
PIN
PIN
10
11
12
13
14
15
23
2
3
5
9
OUT
OD
OD
OD
OD
OD
OD
OD
OD
OD
OD
I/O
OD
IO
IO
I/O
I/O
-
24t
24t
24t
24
24
24
24
24
24
24
24
24
24
24
12t
PRINTER MODE: PD7
Parallel port data bus bit 7. Refer to description of the parallel port
for definition of this pin in ECP and EPP mode.
EXTENSION FDD MODE: This pin is a tri-state output.
EXTENSION 2FDD MODE: DSA2
This pin is for Extension FDD A; its function is the same as the
DSA pin of FDC.
Drive Density Select bit 0.
Drive Density Select bit 1. (CR2A bit 1_0 = 00, default)
General purpose I/O port 1 bit 0. (CR2A bit 1_0 = 01)
Alternate Function from GP10: Interrupt channel input.
KBC P12 I/O port. (CR2A bit 1_0 = 10)
System Control Interrupt (CR2A bit 1_0 = 11)
Head select. This open drain output determines which disk drive
head is active.
Logic 1 = side 0
Logic 0 = side 1
Write enable. An open drain output.
Write data. This logic low open drain writes pre-compensation
serial data to the selected FDD. An open drain output.
Step output pulses. This active low open drain output produces a
pulse to move the head to another track.
Direction of the head step motor. An open drain output.
Logic 1 = outward motion
Logic 0 = inward motion
Motor B On. When set to 0, this pin enables disk drive 1. This is
an open drain output.
Drive Select A. When set to 0, this pin enables disk drive A. This
is an open drain output.
Drive Select B. When set to 0, this pin enables disk drive B. This
is an open drain output.
-14-
FUNCTION
FUNCTION
Publication Release Date: April 1998
W83977TF
PRELIMINARY
Revision 0.62