Highlights
s A special Plug and Play (PnP) module that includes:
— Flexible IRQs, DMAs and base addresses that meet
the Plug and Play requirements specified by Mi-
crosoft® in their 1995 hardware design guide for
Windows® and Plug and Play ISA Revision 1.0A
— Plug and Play ISA mode (with isolation mechanism
– Wait for Key state)
— Motherboard Plug and Play mode
s A Floppy Disk Controller (FDC) that provides:
— A modifiable address that is referenced by a 16-bit
programmable register
— Software compatibility with the PC8477, which con-
tains a superset of the floppy disk controller func-
tions in the µDP8473, the NEC µPD765A and the
N82077
— 13 IRQ channel options
— Four 8-bit DMA channel options
— 16-byte FIFO
— Burst and non-burst modes
— A high-performance, internal, digital data separator
that does not require any external filter components
— Support for standard 5.25" and 3.5" floppy disk
drives
— Automatic media sense support
— Perpendicular recording drive support
— Three-mode Floppy Disk Drive (FDD) support
— Full support for the IBM Tape Drive Register (TDR)
implementation of AT and PS/2 drive types
s A Keyboard and mouse Controller (KBC) with:
— A modifiable address that is referenced by a 16-bit
programmable register, reported as a fixed address
in resource data
— 13 IRQ options for the keyboard controller
— 13 IRQ options for the mouse controller
— An 8-bit microcontroller
— Software compatibility with the 8042AH and
PC87911 microcontrollers
— 2 KB of custom-designed program ROM
— 256 bytes of RAM for data
— Five programmable dedicated open drain I/O lines
for keyboard controller applications
— Asynchronous access to two data registers and one
status register during normal operation
— Support for both interrupt and polling
— 93 instructions
— An 8-bit timer/counter
— Support for binary and BCD arithmetic
— Operation at 8 MHz,12 MHz or 16 MHz (programma-
ble option)
— Can be customized using the PC87323VUL, which
includes a RAM-based KBC, as a development plat-
form for keyboard controller code
s A Real-Time Clock (RTC) that has:
— A modifiable address that is referenced by a 16-bit
programmable register
— 13 IRQ options, with programmable polarity
— DS1287, MC146818 and PC87911 compatibility
— 242 bytes of battery backed up CMOS RAM in two
banks
— Selective lock mechanism for the RTC RAM
— Battery backed up century calendar in days, days of
the week, months and years, with automatic leap-
year adjustment
— Battery backed-up time of day in seconds, minutes
and hours that allows a 12 or 24 hour format and ad-
justments for daylight savings time
— BCD or binary format for time keeping
— Three different maskable interrupt flags:
• Periodic interrupts - At intervals from 122 msec
to 500 msec
• Time-of-day alarm - At intervals from once per
second to once per day
• Updated Ended Interrupt - Once per second
upon completion of update
— Separate battery pin, 2.4 V operation that includes
an internal UL protection resistor
— 2 µA maximum power consumption during power
down
— Double-buffer time registers
s An Advanced Power supply Control (APC) that controls
the main power supply to the system, using open-drain
output, as follows:
Power turned on when:
— The RTC reaches a pre-determined date and time.
— A high to low transition occurs on the RI input signals
of the UARTs.
— A ring pulse or pulse train is detected on the RING
input signal.
— A SWITCH input signal indicates a Switch On event
Powered turned off when:
— A SWITCH input signal indicates a Switch Off event
— A Fail-safe event occurs (power-save mode detect-
ed but the system is hung up).
— Software turns power off.
s Two UARTs that provide:
— Software compatibility with the 16550A and the
16450
— A modifiable address that is referenced by a 16-bit
programmable register
— 13 IRQ channel options
— Shadow register support for write-only bits
— Four 8-bit DMA options for the UART with Infrared
support (UART2)
s An enhanced UART and Infrared (IR) interface on the
UART2 that supports:
— UART data rates up to 1.5 Mbaud
— IrDA 1.0 SIR
— ASK-IR option of SHARP-IR
— DASK-IR option of SHARP-IR
— Consumer-IR (TV-Remote) circuitry
— A Plug and Play compatible external transceiver
s A bidirectional parallel port that includes:
— A modifiable address that is referenced by a 16-bit
programmable register
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