Question: In the coprocessor mode, can we apply an external interrupt?
Answer: There are only two general purpose external hardware interrupts which you have found on GPIO24 and GPIO25 for EZ-Host. These two interrupts are enabled and controlled in the GPIO Control Register 0xC006. In addition the Interrupt Enable Register 0xC00E has a GPIO Interrupt Enable bit which is the global enable for these two interrupts (IRQ1 and IRQ0), this bit must be set appropriately as well.
The GPIO25 interrupt functions the same regardless of standalone or coprocessor mode. GPIO24 is used for the HPI interrupt or in HPI mode or used as IOReady in IDE mode. If either HPI or IDE is enabled, then GPIO24 is no longer a general purpose interrupt.
