
W83977EF/ CTF
PRELIMINARY
Publication Release Date: March 1999
-8 -
Revision A1
1.1 Host Interface, continued
SYMBOL
PIN
I/O
FUNCTION
IRQ14
GP14
(GPACS1#)
103
OUT
12t
I/O
12t
Interrupt request 14. (CR2C bit 1_0 = 00, default)
General purpose I/O port 1 bit 4. (CR2C bit 1_0 = 01)
Alternate Function 1 from GP14: General purpose address
decode output.
Alternate Function 2 from GP14: KBC P17 I/O port.
Power LED output. (CR2C bit 1_0 = 10)
(P17)
PLEDO
OUT
12t
OUT
12t
I/O
12t
IRQ15
GP15
(GPACS2#)
104
Interrupt request 15.(CR2C bit 3_2 = 00, default)
General purpose I/O port 1 bit 5. (CR2C bit 3_2 = 01)
Alternate Function 1 from GP15: General purpose address write
enable output.
Alternate Function 2 from GP15: KBC P12 I/O port.
Watch-Dog timer output. (CR2C bit 3_2 = 10)
(P12)
WDT
OUT
12t
IN
t
CLKIN
1
24 or 48 MHz clock input, selectable through bit 5 of CR24.
1.2 General Purpose I/O Port
SYMBOL
PIN
I/O
FUNCTION
PWR_CTL#
GP20
(KBRST)
69
OD
16u
I/O
16tu
Power supply control
General purpose I/O port 2 bit 0.
Alternate Function from GP20: Keyboard reset (KBC P20)
SMI #
70
OD
12t
System Management Interrupt. (CR2B bit 4_3 = 00, default)
In the legacy power management mode, SMI# is drive low by the
power management events.
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)
GP21
(P13)
P16
I/O
12t
I/O
12t
OD
12t
I/O
12t
PANSWOT#
GP22
72
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.
(P14)