Increased power consumption due to FPU even with FPU interrupt handling

[Bylos]

Hi all,

I am calling arm_rfft_fast_f32 which uses the FPU on the nRF52840.

Unfortunately when I disconnect from BLE connection and stop advertising, the consumption remain around ~600 uA, while if this function is not used the consumption decrease to 2~4 uA.

I try to implement both methods to handle FPU interrupts with no success... Is there anyway I can check if interrupts are properly cleared ?

Best regards,

[Vidar Berg]

Hello,

The system will never enter sleep if the interrupt is not being properly cleared, so I'm not sure if this could be related to the FPU. Is the 600uA measured as an average across multiple wake-up and sleep cycles, or does 600 uA become the new floor/base current after arm_rfft_fast_f32  is completed? Maybe you could share a minimal version of your project so I can try to replicate it here?

Best regards,

Vidar