w83977eg Winbond Electronics Corp America, w83977eg Datasheet - Page 13

• Manufacturer Part Number: w83977eg
• Description: Winbond Isa I/o W83977ef W83977eg
• Manufacturer: Winbond Electronics Corp America

4.2
4.3
PWR_CTL#
GP20
(KBRST)
SMI #
GP21
(P13)
P16
PANSWOT#
GP22
(P14)
PANSWIN#
GP23
(P15)
SUSC#
(GA20)
GP25
CTSA#
CTSB#
DSRA#
DSRB#
RTSA#
HEFRAS
SYMBOL
SYMBOL
General Purpose I/O Port
Serial Port Interface
PIN
41
48
42
49
43
PIN
69
70
72
73
39
I/O
OD
OD
OD
I/O
I/O
I/O
I/O
I/O
I/O
IN
I/O
IN
IN
I/O
IN
16tu
16u
12t
12t
12t
12t
12t
12t
ts
8t
12
t
t
t
Clear To Send is the modem control input.
The function of these pins can be tested by reading Bit 4 of the
handshake status register.
Data Set Ready. An active low signal indicates the modem or
data set is ready to establish a communication link and transfer
data to the UART.
UART A Request To Send. An active low signal informs the
modem or data set that the controller is ready to send data.
During power-on reset, this pin is pulled down internally and is
defined as HEFRAS, which provides the power-on value for
CR26 bit 6 (HEFRAS). A 4.7 kΩ is recommended if intends to
pull up. (select 370H as configuration I/O port′s address)
Power supply control
General purpose I/O port 2 bit 0.
Alternate Function from GP20: Keyboard reset (KBC P20)
For the power management, the SMI is active low by the power
management events, that generate and SCI in ACPI mode.
(CR2B bit 4_3 = 00, default)
General purpose I/O port 2 bit 1. (CR2B bit 4_3 = 01)
Alternate Function from GP21: KBC P13 I/O port.
KBC P16 I/O port. (CR2B bit 4_3 = 10)
Panel Switch output. (CR2B bit 5 = 0, default)
General purpose I/O port 2 bit 2. (CR2B bit 5 = 1)
Alternate Function from GP22: KBC P14 I/O port.
Panel Switch input. (CR2B bit 7_6 = 00, default)
General purpose I/O port 2 bit 3. (CR2B bit 7_6 = 01)
Alternate Function from GP23: KBC P15 I/O port
Suspend C input
Alternate Function from GP25: GATE A20 (KBC P21)
General purpose I/O port 2 bit 5.
W83977EF-AW/W83977EG-AW
-11-
FUNCTION
FUNCTION
Publication Release Date: Apr. 2006
Revision 1.2