Interrupt priority

[Artem Zemlyanukhin]

Hi,

While the softdevice is active (nRF51822) available interrupt priorities are:

typedef enum { NRF_APP_PRIORITY_HIGH = 1, NRF_APP_PRIORITY_LOW = 3 } nrf_app_irq_priority_t;

1. Can I use interrupt priority = 2?
2. SVC priority is 2, is it true? So I could't use Softdevice api-functions in interrupt handlers with NRF_APP_PRIORITY_HIGH priority?
3. What does define "#define NRF_APP_PRIORITY_THREAD 4" in app_util.h mean?

Artem Z. Best Regards

[Audun]

Hi Artem,

to answer your questions

• 1. Can I use interrupt priority = 2? No, not while the SoftDevice is active. If you try to set this priority level using sd_nvic_SetPriority() you will get an error.
• 2. SVC priority is 2, is it true? So I could't use Softdevice api-functions in interrupt handlers with NRF_APP_PRIORITY_HIGH priority? Correct. You would need to pass execution to a lower priority level, for example by using a software interrupt (SWIRQ) with NRF_APP_PRIORITY_LOW.
• 3. What does define "#define NRF_APP_PRIORITY_THREAD 4" in app_util.h mean? It's used in "current_int_priority_get()" to indicate if the CPU is running in thread mode (main context), as opposed to running in interrupt mode with interrupt priority 0-3.

[Audun]

I'll have to check with someone more intimately familiar with the stack to answer this question. Let me get back to you!