
3
TABLE OF CONTENTS
FEATURES.......................................................................................................................... 1
GENERAL DESCRIPTION................................................................................................... 5
DESCRIPTION OF PIN FUNCTIONS.................................................................................. 7
BUFFER TYPE DESCRIPTIONS........................................................................................12
REFERENCE DOCUMENTS ..............................................................................................14
FUNCTIONAL DESCRIPTION............................................................................................15
SUPER I/O REGISTERS.................................................................................................15
HOST PROCESSOR INTERFACE..................................................................................15
FLOPPY DISK CONTROLLER ...........................................................................................16
FDC INTERNAL REGISTERS......................................................................................16
COMMAND SET/DESCRIPTIONS...............................................................................41
Force Write Protect......................................................................................................70
SERIAL PORT (UART) .......................................................................................................71
REGISTER DESCRIPTION..........................................................................................71
INFRARED INTERFACE.....................................................................................................87
PARALLEL PORT...............................................................................................................88
IBM XT/AT COMPATIBLE, BI-DIRECTIONAL AND EPP MODES ......................................90
EXTENDED CAPABILITIES PARALLEL PORT ..................................................................96
PARALLEL PORT FLOPPY DISK CONTROLLER.........................................................109
POWER MANAGEMENT..................................................................................................111
FDC Power Management...........................................................................................111
UART Power Management.........................................................................................115
Parallel Port...............................................................................................................115
V
BAT
Support...............................................................................................................115
V
TR
Support................................................................................................................115
Internal PWRGOOD...................................................................................................116
CIRCC PLL Power Control.........................................................................................116
32.768 kHz Standby Clock Output..............................................................................116
BIOS BUFFER..................................................................................................................122
GENERAL PURPOSE I/O.................................................................................................123
Description.................................................................................................................123
RUN STATE GPIO DATA REGISTER ACCESS........................................................125
GPIO OPERATION....................................................................................................127
8042 KEYBOARD CONTROLLER DESCRIPTION ...........................................................129
RTC INTERFACE .............................................................................................................138
SOFT POWER MANAGEMENT .......................................................................................148
ACPI/PME/SMI FEATURES..............................................................................................152
ACPI Features............................................................................................................152
Wake Events..............................................................................................................153
PME SUPPORT.........................................................................................................154
ACPI/PME/SMI REGISTERS.........................................................................................155
Register Description...................................................................................................155
Wakeup Event Configuration is Retained by Battery Power........................................155
Register Block............................................................................................................156