AT89LP6440 datasheet(82/194 Pages) ATMEL

82 / 194 page

3706A–MICRO–9/09

AT89LP6440 - Preliminary

another interrupt will be generated. Both INT0 and INT1 may wake up the device from the

Power-down state.

15. General-purpose Interrupts

The General-purpose Interrupt (GPI) function provides 8 configurable external interrupts on

Port 1. Each port pin can detect high/low levels or positive/negative edges. The GPIEN register

select which bits of Port 1 are enabled to generate an interrupt. The GPMOD and GPLS regis-

ters determine the mode for each individual pin. GPMOD selects between level-sensitive and

edge-triggered mode. GPLS selects between high/low in level mode and positive/negative in

edge mode. A block diagram is shown in Figure 15-1. The pins of Port 1 are sampled every

clock cycle. In level-sensitive mode, a valid level must appear in two successive samples before

generating the interrupt. In edge-triggered mode, a transition will be detected if the value

changes from one sample to the next. When an interrupt condition on a pin is detected, and that

pin is enabled, the appropriate flag in the GPIF register is set. The flags in GPIF must be cleared

by software. Any GPI interrupt may wake up the device from the Power-down state.

Figure 15-1. GPI Block Diagram

(P1.2) GPI2

(P1.1) GPI1

(P1.0) GPI0

(P1.3) GPI3

(P1.6) GPI6

(P1.5) GPI5

(P1.4) GPI4

(P1.7) GPI7

GPMOD

GPLS

GPIEN

GPIF

Interrupt

CLK

AT89LP6440 Datasheet(PDF) 82 Page - ATMEL Corporation