SAM4L Datasheet, PDF (535/1185 Pages) ATMEL Corporation – ATSAM ARM-based Flash MCU

ATSAM4L4/L2
or to use the GPIO interrupts. After configuring the GPIO, the CLK_GPIO can be disabled by
writing to the Power Manager if interrupts are not used.
If the CPU Local Bus is used to access the configuration interface of the GPIO, the CLK_GPIO
must be equal to the CPU clock to avoid data loss.
23.5.3 Interrupts
The GPIO interrupt request lines are connected to the NVIC. Using the GPIO interrupts requires
the NVIC to be programmed first.
23.5.4
Peripheral Events
The GPIO peripheral events are connected via the Peripheral Event System. Refer to Section
31. ”Peripheral Event Controller (PEVC)” on page 839 for details.
23.5.5
Debug Operation
When an external debugger forces the CPU into debug mode, the GPIO continues normal oper-
ation. If the GPIO is configured in a way that requires it to be periodically serviced by the CPU
through interrupts or similar, improper operation or data loss may result during debugging.
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