How To Remove Debug Interface on NRF52832

[Sami]

Hello,

I can successfully put my nRF52832 into System OFF mode, however, the Debug Mode Interface is still running, so the current consumption is > 2mA. What are the command(s)/Soft Device APIs to truly take the system out of Debug Mode? I'm using SDK v11.0.0 and S132. I'm reading a lot of information on other posts, but none that pertain to SDK v11.0.0 with the Soft Device running S132. Please assist, thank you. 

Please note, I've already tried removing all the debug hardware and battery after flashing and re-attaching the battery, but still not getting the correct results. Thanks!

Best,

Sami

[Jared]

Hi,

Are you using a custom board? sd_flash_protect are used to set the flash protection config registers.

regards

Jared

[Sami]

Yes, I am using a custom board. I thought we use sd_flash_protect() to write to the UCIR register to take the nRF out of debug mode interface by writing

"NRF_UICR->APPROTECT = 0xFF"

What is the proper way to take the nRF52832 out of debug mode interface? Maybe sd_flash_protect() is not the correct API? I'm using SDK v11.0.0.

[Sami]

Thank you Nguyen, my next analysis is to characterize leaks on my custom board.

Jared, unfortunately, I cannot send my .hex file. Can't you check debug mode with a read on

DWT->CYCCNT ?

Also, don't I need to call 

  this: gpio_interrupt_disable();

or

this: nrf_gpio_input_disconnect();

on all non-used GPIOs that while I'm in System OFF mode?

[Sami]

     nrf_gpio_input_disconnect( pinID ); // Currently calling this

     gpio_interrupt_disable( pinID );       // Currently calling this

     nrf_drv_gpiote_in_uninit( pinID );    // Currently calling this

[Jared]

Hi,

I'm not sure if it only specifies if the probes are connected to the SWD interface or also if it's in debug mode. Could you try flashing your custom board with the Power Profiling application and see what current consumption you measure? Could you also describe how you measure the current in more detail?

Yes, you should set the GPIO pins as inputs and de initialize the GPIO buffer. This will prevent the GPIO pins from floating. You can read the state of each GPIO pins by reading the PIN_CNF[N] registers.

regards

Jared

[Sami]

Oh, then my code is incorrect? You mention that I need to set the GPIO pins as inputs. Therefore I need to remove my call to nrf_gpio_input_disconnect( pinID ) and replace with: 

nrf_gpio_cfg_watcher( pinID ); // Set GPIO pins as inputs

gpio_interrupt_disable( pinID ); // Disable interrupts

nrf_drv_gpiote_in_uninit( pinID ); // Uninitialize

Can you please confirm? Thanks!

[RK]

one question - are you just doing a soft reset after flashing or have you tried completely power cycling the board by removing and re-attaching power? It's never been clear to me that a soft reset resets the debug interface. 

[Sami]

RK, I have physically performed a hard reset on the board, removed all debug (SWD) connections and UART connections, and removed re-attached the battery. That should do the trick according to the Nordic Application engineers.