4.7 __enable_irq intrinsic

This intrinsic enables IRQ interrupts.

To use this intrinsic, your source file must contain #include <arm_compat.h>. This is only available for targets in AArch32 state.


Typically, this intrinsic enables IRQ interrupts by clearing the I-bit in the CPSR. However, for Cortex®‑M profile processors, it clears the exception mask register (PRIMASK).


void __enable_irq(void)


The __enable_irq intrinsic can only be executed in privileged modes, that is, in non-user modes. In User mode this intrinsic does not change the interrupt flags in the CPSR.

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