Reset issue, reason 0x00

[Peer]

Dear support team,

I have some trouble with a custom board using the NRF51822. Sometimes the MCU resets supuriously.

After reset I try to find out the reason by reading NRF_POWER->RESETREAS directly and using sd_power_reset_reason_get(&uint32). The results are different:

• NRF_POWER->RESETREAS: 0x00 or 0x01 (Mostly it returns 0x00 but sometimes 0x01)

• sd_power_reset_reason_get: It does not touch the given pointer.

It seems the problem occurs with high interrupt load. (Many interrupts from BLE-softdevice, PWM generating timer, ...)

What can I do to track down the problem. Is there a possibility to disable the external reset pin for testing? What other thinks can be responsible for MCU resets (especially with reason 0x00).

Thank you and best, Peer

[Peer]

Hi all,

here is what I found out recently. I guess the nRF likes to catch up resets (spikes) from a reset line which is pulled up weakly. If I connect the NRESET line directly to it's supply the problem never occurs anymore. (The problem is that I'm update to program+debug in this state.)

Reset reason 0x00 seems to indicate a normal power up reset. Best, Peer

[Milk]

Hi, similarly,sometimes the 51822 reset suprised,but by reading the NRF_POWER->RESETREAS,the value sometimes is 0x04 or 0x06.The project contains the WDT.But what does the bit SREQ of the NRF_POWER->RESETREAS means?When does the bit SREQ change to be 1?