W83977G Winbond Electronics Corp America, W83977G Datasheet - Page 23

• Manufacturer Part Number: W83977G
• Description: W83877TF plus KBC, CIR, RTC, Pb-free
• Manufacturer: Winbond Electronics Corp America

4.6
DRVDEN0
DRVDEN1
GP10
(IRQIN1)
P12
DSRC
HEAD
DIR
MOB
DSA
DSB
MOA
DSKCHG
RDATA
INDEX
WE
WD
STEP
WP
TRAK0
SYMBOL
W83977F-A/ W83977G-A/ W83977AF-A/ W83977AG-A
FDC Interface
PIN
10
11
12
13
14
15
16
17
2
3
5
9
4
6
7
8
OD 24
OD 24
OD 24
OD 24
OD 24
OD 24
OD 24
OD 24
OD 24
OD 24
OD 24
IN cs
IN cs
IN cs
IN cs
IN cs
I/O
Drive Density Select bit 0.
Drive Density Select bit 1.
Alternate Function 1: General purpose I/O port 1, bit 0. It can be configured
as an interrupt channel.
Alternate Function 2: Keyboard P12 I/O port.
Alternate Function 3:
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 precompensation 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.
Motor A On. When set to 0, this pin enables disk drive 0. This is an open
drain output.
Diskette change. This signal is active low at power on and when the diskette
is removed. This input pin is pulled up internally by a 1 K  r esistor, which can
can be disabled by bit 7 of L0-CRF0 (FIPURDWN).
The read data input signal from the FDD. This input pin is pulled up internally
by a 1 K
Write protected. This active low Schmitt input from the disk drive indicates
that the diskette is write-protected. This input pin is pulled up internally by a 1
K
Track 0. This Schmitt-triggered input from the disk drive is active low when
the head is positioned over the outermost track. This input pin is pulled up
internally by a 1 K
(FIPURDWN).
This Schmitt-triggered input from the disk drive is active low when the head is
positioned over the beginning of a track marked by an index hole. This input
pin is pulled up internally by a 1 K
L0-CRF0 (FIPURDWN).
resistor, which can be disabled by bit 7 of L0
resistor, which can be disabled by bit 7 of L0
-15 -
resistor, which can be disabled by bit 7 of L0
DSR
input of UART C [W83977AF only]
FUNCTION
resistor, which can be disabled by bit 7 of
Publication Release Date: May 2006
-CRF0 (FIPURDWN).
-CRF0 (FIPURDWN).
-CRF0
Revision 0.60