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Interrupts, External interrupt inputs, External interrupt pin glitch suppression – Philips P89LPC903 User Manual

Page 37

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Philips Semiconductors

User’s Manual - Preliminary -

P89LPC901/902/903

INTERRUPTS

2003 Dec 8

37

External Interrupt Inputs

The P89LPC901/902/903 have a Keypad Interrupt function (see Keypad Interrupt (KBI) on page 79). This can be used as an
external interrupt input. If enabled when the P89LPC901/902/903 is put into Power down or Idle mode, the keypad interrupt will
cause the processor to wake up and resume operation. Refer to the section on Power Reduction Modes for details.

External Interrupt Pin Glitch Suppression

Most of the P89LPC901/902/903 pins have glitch suppression circuits to reject short glitches (please refer to the P89LPC901/
902/903 datasheet, AC Electrical Characteristics for glitch filter specifications) .

Figure 3-1: Interrupt sources, enables, and Power down Wake-up sources - P89LPC901

Wakeup (if in
Power down)

EA (IE0.7)

Interrupt to CPU

BOPD

EBO

KBIF

EKBI

EC

WDOVF

EWDRT

TF0

ET0

TF1

ET1

CMF

ERTC

(RTCCON.1)

RTCF

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