4.2.1. Generating an interrupt

You can make the processor take the FIQ or IRQ exceptions (provided that interrupts are enabled) by asserting the nFIQ or nIRQ inputs, respectively.It is essential that, once asserted, the interrupt input remains asserted until the processor acknowledges to the source of the interrupt that the interrupt has been taken. This acknowledgement usually occurs when the interrupt service routine accesses the peripheral causing the interrupt, for example:

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