MCU reboots when the radio is in RX state and power management is used.

RE: MCU reboots when the radio is in RX state and power management is used.

Vidar Berg — Wed, 13 Jan 2021 14:46:58 GMT

Thanks for confirming. Value 4 is actually corresponding to the SREQ bit (soft reset), and is a much more common reset source. This bit will be set after the device is reset by the debugger (e.g. after programming), or if the application has run the NVIC_SystemReset() function (typically from the app_error_fault_handler()).

Lockup reset can happen if you are really unlucky and trigger a hardfault within a hardfault. Fortunalely, that doesn't happen too often.

[quote user="Damien Piguet"]I have also tried my code on the PCA10056 development kit, and it works in that case. One notable difference with my own custom board is the use of a RV-3028-C7 RTC for the clock signal[/quote]

Intereseting that it doesn't happen with the DK. On the custom board, does the issue also occur in debug mode, or do you have to disconnect the debugger to reproduce the problem?

RE: MCU reboots when the radio is in RX state and power management is used.

Damien Piguet — Tue, 12 Jan 2021 14:34:37 GMT

Hello Vidar,

Thank you for your response,

The code does not fall into app_error_fault_handler().

On the Logical analyser, RESETREAS is always zero at start-up. In the debugger, I saw value 4 (CPU lock-up) but I am not sure this is a right catch. Just in case, what could cause a CPU lock-up ?

I have also tried my code on the PCA10056 development kit, and it works in that case. One notable difference with my own custom board is the use of a RV-3028-C7 RTC for the clock signal. Otherwise there is no other peripheral when I test. The problem happens when the radio is receiving, and in certain situations, when transmitting.

In summary there is something wrong when the radio is active and the CPU is not. Does that ring a bell with respect to the other situations you have encountered ?

Thanks and best regards,

Damien

RE: MCU reboots when the radio is in RX state and power management is used.

Vidar Berg — Tue, 12 Jan 2021 10:06:39 GMT

Hello Damien,

Are you able to debug the application to see if the program ends up in the app_error_fault_handler() function inside the SDK Error module? This function will by default perform a system reset if invoked.

You may also want to check the reset source on boot by reading the RESETREAS register (NRF_POWER->RESETREAS). Just remember to clear it after reading it as it is a retained register. See the Reset behavior table too see which reset source will clear this register.

Best regards,

Vidar