MC68HC908LJ12 Datasheet, PDF (362/413 Pages) Freescale Semiconductor, Inc – 8-bit microcontroller units

Technical Data — MC68HC908LJ12
Section 19. Keyboard Interrupt Module (KBI)
19.1 Contents
19.2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363
19.3 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
19.4 I/O Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
19.5 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .365
19.5.1 Keyboard Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . 367
19.6 Keyboard Interrupt Registers . . . . . . . . . . . . . . . . . . . . . . . . . 367
19.6.1 Keyboard Status and Control Register. . . . . . . . . . . . . . . . 368
19.6.2 Keyboard Interrupt Enable Register . . . . . . . . . . . . . . . . . . 369
19.7 Low-Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
19.8 Wait Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
19.9 Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370
19.10 Keyboard Module During Break Interrupts . . . . . . . . . . . . . . . 370
19.2 Introduction
The keyboard interrupt module (KBI) provides eight independently
maskable external interrupts which are accessible via PTA0–PTA3 and
PTD4–PTD7. When a port pin is enabled for keyboard interrupt function,
an internal 30kΩ pullup device is also enabled on the pin.
MC68HC908LJ12 — Rev. 2.1
Freescale Semiconductor
Keyboard Interrupt Module (KBI)
Technical Data
363