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TABLE OF CONTENTS
FEATURES ....................................................................................................................................... 1
GENERAL DESCRIPTION................................................................................................................. 5
DESCRIPTION OF PIN FUNCTIONS ................................................................................................ 7
BUFFER TYPE DESCRIPTIONS........................................................................................ 10
GENERAL PURPOSE I/O PINS....................................................................................................... 11
REFERENCE DOCUMENTS ........................................................................................................... 12
FUNCTIONAL DESCRIPTION......................................................................................................... 14
SUPER I/O REGISTERS.................................................................................................... 14
HOST PROCESSOR INTERFACE..................................................................................... 14
FLOPPY DISK CONTROLLER ........................................................................................................ 15
FDC INTERNAL REGISTERS.......................................................................................................... 15
COMMAND SET/DESCRIPTIONS................................................................................................... 38
INSTRUCTION SET ........................................................................................................................ 41
DATA TRANSFER COMMANDS........................................................................................ 53
CONTROL COMMANDS.................................................................................................... 62
SERIAL PORT (UART).................................................................................................................... 69
INFRARED INTERFACE.................................................................................................... 85
PARALLEL PORT............................................................................................................................ 86
IBM XT/AT COMPATIBLE, BI-DIRECTIONAL AND EPP MODES....................................... 88
EXTENDED CAPABILITIES PARALLEL PORT................................................................................ 94
OPERATION.....................................................................................................................102
PARALLEL PORT FLOPPY DISK CONTROLLER...........................................................................107
POWER MANAGEMENT................................................................................................................109
UART POWER MANAGEMENT........................................................................................113
PARALLEL PORT.............................................................................................................113
INTERNAL PWRGOOD....................................................................................................113
32.768
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Z
STANDBY CLOCK OUTPUT...........................................................................114
SERIAL IRQ...................................................................................................................................115
BIOS BUFFER................................................................................................................................120
GENERAL PURPOSE I/O...............................................................................................................121
DESCRIPTION .................................................................................................................121
RUN STATE GPIO DATA REGISTER ACCESS................................................................122
GPIO CONFIGURATION..................................................................................................123
WATCH DOG TIMER.....................................................................................................................126
8042 KEYBOARD CONTROLLER DESCRIPTION..........................................................................128
SOFT POWER MANAGEMENT......................................................................................................136
BUTTON OVERRIDE FEATURE.......................................................................................139