Freescale Semiconductor, Inc.
Keyboard/External Interrupt Module (KBI)
14.3 Features
Features of the KBI include:
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Dedicated external interrupt pin (IRQ1)
Six keyboard interrupt pins with separate keyboard interrupt
enable bits and one keyboard interrupt mask
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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
184
MC68HC908RFRK2
Keyboard/External Interrupt Module (KBI)
MOTOROLA
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