RE: nRF52840 interrupt causing reset

Jørgen Holmefjord — Thu, 30 Jun 2022 15:13:38 GMT

Thw Zephyr RTOS likely generates its own vector and ISR tables based on the IRQ_(DIRECT_)CONNECT macros during build-time, see this comment.

RE: nRF52840 interrupt causing reset

MarekU — Mon, 27 Jun 2022 16:57:33 GMT

This is my whole application, I edit my post to add main.c file.

It's working now! Thank you. Can you tell me, why this is working, and "direct api" is not? What's the difference?

/**
 * @brief Initialize a 'direct' interrupt handler.
 *
 * This routine initializes an interrupt handler for an IRQ. The IRQ must be
 * subsequently enabled via irq_enable() before the interrupt handler begins
 * servicing interrupts.
 *
 * These ISRs are designed for performance-critical interrupt handling and do
 * not go through common interrupt handling code. They must be implemented in
 * such a way that it is safe to put them directly in the vector table.  For
 * ISRs written in C, The ISR_DIRECT_DECLARE() macro will do this
 * automatically. For ISRs written in assembly it is entirely up to the
 * developer to ensure that the right steps are taken.
 *
 * This type of interrupt currently has a few limitations compared to normal
 * Zephyr interrupts:
 * - No parameters are passed to the ISR.
 * - No stack switch is done, the ISR will run on the interrupted context's
 *   stack, unless the architecture automatically does the stack switch in HW.
 * - Interrupt locking state is unchanged from how the HW sets it when the ISR
 *   runs. On arches that enter ISRs with interrupts locked, they will remain
 *   locked.
 * - Scheduling decisions are now optional, controlled by the return value of
 *   ISRs implemented with the ISR_DIRECT_DECLARE() macro
 * - The call into the OS to exit power management idle state is now optional.
 *   Normal interrupts always do this before the ISR is run, but when it runs
 *   is now controlled by the placement of a ISR_DIRECT_PM() macro, or omitted
 *   entirely.
 *
 * @warning
 * Although this routine is invoked at run-time, all of its arguments must be
 * computable by the compiler at build time.
 *
 * @param irq_p IRQ line number.
 * @param priority_p Interrupt priority.
 * @param isr_p Address of interrupt service routine.
 * @param flags_p Architecture-specific IRQ configuration flags.
 */
 #define IRQ_DIRECT_CONNECT(irq_p, priority_p, isr_p, flags_p) \
	ARCH_IRQ_DIRECT_CONNECT(irq_p, priority_p, isr_p, flags_p)

It's sounds like this method should be used in user code. Is that a case?

RE: nRF52840 interrupt causing reset

Jørgen Holmefjord — Mon, 27 Jun 2022 16:41:55 GMT

Hi,

Is this part of a larger application, or is this your whole application?

Can you try to use the Zephyr APIs to connect the interrupt to the handler?

IRQ_DIRECT_CONNECT(UARTE0_UART0_IRQn, 6, UART0_IRQHandler, 0);
irq_enable(UARTE0_UART0_IRQn);

Best regards,
Jørgen