Interrupt priority

[Jim]

     The following description of SPI_DEFAULT_CONFIG_IRQ_PRIORITY in sdk_config.h has the following description: <i> Priorities 0,2 (nRF51) and 0,1,4,5 (nRF52) are reserved for SoftDevice, is it possible for all peripherals to use priority 0,1 , 4, 5? If I set the SPI priority to the highest 0, will the BLE connection be affected?
     Test environment: nrf52832, SDK14.2, SPI off DMA case。

[haakonsh]

Hey Jim,

In short, yes! You cannot mess with the priorities below 2 while using the SoftDevice, but you can do whatever you want with priorities 8-127. See Interrupt model and processor availability, and the app_irq_priority_t definition in app_util_platform.h in SDK15. 


-Edit:
Previous answer is incorrect as we've only implemented 3 piority bits (CPU and support module configuration). From Fig 1. in Interrupt priority levels you'll see that piority levels 2-3 and 5-7 are available to the application. Do note that changing the priority levels of peripheral drivers and libraries may cause other libraries or drivers to fail, depending on the nature of the lowered priority interrupt. 

Cheers,

Håkon.