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PC87591E/S/L
Features (Continued)
■Interrupt Control Unit (ICU)
—31 maskable vectored interrupts (of which 26 are ex-
ternal)
—General-purpose external interrupt inputs through
MIWU
—Enable and pending indication for each interrupt
—Non-maskable interrupt input
■Multi-Input Wake-Up (MIWU)
—Supports up to 32 wake-up or interrupt inputs
—Generates wake-up event to PMC (Power Manage-
ment Controller)
—Generates interrupts to ICU
—Provides user-selectable trigger conditions
■General-Purpose I/O (GPIO)
—84/117 port pins in 128-pin/176-pin package, re-
spectively.
—I/O pins individually configured as input or output
—Configurable internal pull-up resistors
—Special ports for internal keyboard matrix scanning
❏16 open-collector outputs
❏Eight Schmitt inputs with internal pull-ups
—Input for system On/Off switch
—27 external wake-up events
—Low-cost external GPIO expansion through the
BIU I/O Expansion protocol
■PS/2 Interface
—Supports four external ports: Keyboard, mouse and
two additional pointing devices
—Supports byte-level handling via hardware accelera-
tor
■Two ACCESS.bus (ACB) Interface modules. Each is:
—Intel SMBus® and Philips I2C® compatible
—ACCESS.bus master and slave
—Up to three simultaneous slave addresses detected
—Supports polling and interrupt controlled operation
—Generates a wake-up signal on detection of a Start
Condition while in Idle mode
—Optional internal pull-up on SDA and SCL pins
■Two 16-bit Multi Function Timer (MFT16) modules.
Each module:
—Contains two 16-bit timers
—Supports Pulse Width Modulation (PWM), Capture
and Counter
■Universal Synchronous/ Asynchronous Receiver-trans-
mitter (USART)
—A full-duplex USART channel
—Programmable baud rate
—Data transfer via interrupt or polling
—Synchronous mode with either internal or external
clock
—7-, 8- or 9-bit protocols.
■Pulse Width Modulation (PWM) Module
—Eight outputs
—8-bit duty cycle resolution
—Common input clock prescaler
■Timer and WATCHDOG (TWM)
—16-bit periodic interrupt timer with 30 µs resolution
and 5-bit prescaler for system tick and periodic
wake-up tasks
—8-bit WATCHDOG timer
■Analog to Digital Converter (ADC)
—Fourteen channels, with 10-bit resolution
—Sigma-delta technology for high noise rejection
—Three voltage measurements and one temperature
measurement every 100 ms
—Internal voltage reference
■Hardware Monitoring
—Controlled by embedded controller
—System Voltage Measurement
❏Up to eight external measurement points
❏Four internal measurement points
❏Smart power failure detection
—Diode-Based Temperature Measurement
❏Software-controlled fault detection
❏Hardware-monitored over-temperature detection
—Production time calibration using flash parameters
■Digital to Analog Converter (DAC)
—Four channels, 8-bit resolution
—1µs conversion time for 50 pF load
—Full output range from AGND to AVCC
■Analog Comparators Monitor (ACM)
—Eight comparator inputs on KBD scan inputs
—6-bit input measurement resolution
—Scan and Threshold modes
—Supports low-current system wake-up
■Development Support Features
—Interface to debugger via JTAG pins
❏ISE/ADB mode
❏On-board Debug mode
—Flash programing via JTAG
■CR16B Access to Host Controlled Functions
—Enabled when host inactive
Host Controlled Functions Features
■Supports Microsoft®Advanced Power Management
(APM) Specifications Revision 1.2, February 1996
—Generates the System Management Interrupt (SMI)
■PC1 and ACPI Compliant
—PnP Configuration Register structure
—Flexible resource allocation for all logical devices
❏Relocatable base address