
Features
(Continued)
P
Revision 1.2
3
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—
Supports fast tape drives (2 Mbps) and standard
tape drives (1 Mbps, 500 Kbps and 250 Kbps)
I
Keyboard and Mouse Controller (KBC)
—
8-bit
microcontroller,
8042AH and PC87911
—
Standard interface (60h, 64h, IRQ1 and IRQ12)
—
Supports two external swapable PS/2 interfaces for
keyboard and mouse
—
Five programmable, dedicated, open-drain I/O lines
(Fast GA20/P21, KBRST/P20, P12, P16, P17)
software
compatible
with
General-Purpose Modules
I
General-Purpose I/O (GPIO) Ports
—
51 GPIO Ports:
Individually assigned to either LPC or ACB con-
trol (
PC87413 and PC87417
)
46 individually configured as input or output
Five output-only
—
Programmable features for each output pin:
Drive type (open-drain, push-pull or TRI-STATE)
TRI-STATE on V
DD
-fall detection for pins driving
V
DD
-supplied devices
—
Programmable option for internal pull-up resistor on
each input pin
—
Lock option for the configuration and data of each
output pin
—
16 GPIO ports generate IRQ/SIOSMI/SIOSCI for
wake-up events, with individual:
Enable control
Polarity and edge/level selection
Debounce mechanism
—
V
SB
powered
—
Low-cost external GPIO port expansion via X-Bus
(
PC87416 and PC87417
)
I
Real-Time Clock (RTC)
—
DS1287, MC146818 and PC87911 compatible
—
242-byte battery backed-up CMOS RAM in two
banks (accessed through 70-71h and 72-73h)
—
Selective lock mechanisms for the RTC RAM
—
Y2K-compliant calendar, including century and
automatic leap-year adjustment
—
Time of day in seconds, minutes and hours that al-
lows a 12-hour or 24-hour format with optional
adjustment for daylight saving time
—
BCD or binary format for timekeeping
—
Four individually maskable interrupt event flags:
Periodic rates from 122
μ
s to 500 ms
Day-of-month alarm
Time-of-day alarm
Once-per-second to once-per-day
—
Double-buffer time registers
Power Management
I
Supports
ACPI Specification Revision 1.0b, Feb. 2, 1999
I
System Wake-Up Control (SWC)
—
Wake-up request on detection of:
Preprogrammed Keyboard or Mouse sequence
External modem ring from RI1 or RI2 on serial
ports
Predetermined RTC date and time alarm
General-Purpose Input Events from up to 16
GPIO pins
IRQs of internal logical devices
—
Optional routing of power-up request to SERIRQ,
SIOSMI, SIOSCI, PWBTOUT and ONCTL
—
Routing control per input/output event combination
—
Outputs enable/disable per event and system state
combination (ACPI Sx states)
—
Implements bank “b” of the ACPI registers
—
Suspend modes via software emulation (control)
—
Battery-backed event-logic configuration
—
Power button support, featuring:
On/Off control
Power-off, 4-second override
Power button output
—
Sleep Button support
I
Power Supply On/Off control
—
Supports Legacy- and ACPI-compatible Power
button
—
Direct power supply control in response to wake-up
events
—
Programmable Crowbar time-out for On request
—
On/Off control via software emulation
—
Power-fail recovery
I
Enhanced Power Management (PM), including:
—
Special configuration registers for power down
—
Reduced current leakage from pins
—
Low-power CMOS technology
—
Ability to disable all modules
I
Keyboard Events
—
Wake-up on any key
—
Supports programmable 8-byte sequence “pass-
word” for Power Management
—
Simultaneous recognition of three programmable
keys (sequences): “Power”, “Sleep” and “Resume”
I
Power Active Timers
—
Two power-on, elapsed-time counters for the main
(V
DD
) and standby (V
SB
) power supplies
—
32-bit counters with 1 second LSB
—
V
BAT
backed-up counters