Configure CPM2 PORTC pin (PC9) for external interrupt?

Baojun Wang at
Sat Aug 15 00:27:39 EST 2009

hi, list:

  I need to configure CPM2 PORTC pin (PC9) for external interrupt, when I
read the MPC8555ERM.pdf and cpm2-pic.c, I find that PC9 interrupt number is
56, and I request the IRQ in this way:

  hw_irq = 56;
  virq = irq_create_mapping(cpm2_host, hw_irq);

  reqeust_irq(virq, ...);

  I can request the irq successfully, but the interrupt is never generated
(ISR is not called) to the PC9 pins, even though the hardware said an
interrupt was raised. (the hardware have a register with a special bit)

  Should I configure the cpm2 io port first to allow PORTC interrupt? I have
read the cpm2 io port documentation, and I initialize the PC9 as:

  PPARC[pc9_bit] = 0;    /* for general purpose IO, not dedicated */
  PSORC[pc9_bit] = 0;    /* no special option */
  PDIRC[pc9_bit] = 0;     /* for both input/output */

  Am I missing some thing? Any suggestion will be greatly appreciated.

  Best Regards,
- Wang
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