MC68HC908RK2 Datasheet, PDF (182/232 Pages) Motorola, Inc – Microcontroller Unit

Keyboard/External Interrupt Module (KBI)
14.3 Features
Features of the KBI include:
• Dedicated external interrupt pin (IRQ1)
• Six keyboard interrupt pins with separate keyboard interrupt
enable bits and one keyboard interrupt mask
• Internal pullup resistor
• Hysteresis buffer
• Programmable edge-only or edge- and level-interrupt sensitivity
• Automatic interrupt acknowledge
14.4 Functional Description
This section provides a functional description of the keyboard/external
interrupt module (KBI).
14.4.1 External Interrupt
A logic 0 applied to the external interrupt pin (IRQ1) can latch a CPU
interrupt request. Figure 14-1 shows the structure of the external (IRQ1)
interrupt of the KBI module.
A logic 0 applied to one or more of the keyboard interrupt pins can latch
a CPU interrupt request. Figure 14-4 shows the structure of the
keyboard interrupts of the KBI module
See Figure 14-2 for a summary of the interrupt and keyboard
input/output (I/O) registers.
Advance Information
182
Keyboard/External Interrupt Module (KBI)
MC68HC908RK2 — Rev. 4.0
MOTOROLA