Operation; Example Isr - Rabbit 6000 User Manual

7.4 Operation

The following steps must be taken to enable the external interrupts.
1. Write the vector(s) to the interrupt service routine to the external interrupt table.
2. Configure IxCR to select which pins are enabled for external interrupts, what edges are detected on
each pin, and the interrupt priority.
3. When an interrupt occurs for interrupt 0 or 1, read PDDR and/or PEDR to determine which pin has
a signal if more than one pin is enabled for a given external interrupt. Interrupts 2-7 allow only a
single input at any one time.

7.4.1 Example ISR

A sample interrupt handler is shown below.
extInt_isr::
; respond to external interrupt here
; interrupt is automatically cleared by interrupt acknowledge
ipres
ret
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