How to set nRF52 DK into sleep mode: System ON, No RAM retention, wake on RTC (running from the LFXO clock)

RE: How to set nRF52 DK into sleep mode: System ON, No RAM retention, wake on RTC (running from the LFXO clock)

Noah — Tue, 14 Jan 2020 13:25:46 GMT

I have another question regarding cutting SB9 on the DK. I have one board without SB9 cut, and it works perfectly fine. However, I have another DK where I have cut SB9 for power profiling kit use and the board does not function properly. When I try to program the board, I receive an error that says idcode not found. When I jump both pins on P22, I am able to flash the board, but LED1 does not turn on or flash after flashing the rtc example.

Do I really have to solder/desolder SB9 every time I want to flash new code onto the board and then test it using the power profiling kit?

RE: How to set nRF52 DK into sleep mode: System ON, No RAM retention, wake on RTC (running from the LFXO clock)

Noah — Tue, 14 Jan 2020 13:12:24 GMT

Perfect! Thank you so much Simon

RE: How to set nRF52 DK into sleep mode: System ON, No RAM retention, wake on RTC (running from the LFXO clock)

Simonr — Tue, 14 Jan 2020 13:03:30 GMT

Hi Noah

You're correct in that sd_power_system_off() sets the device to system OFF mode. sd_app_evt_wait() will set the device into System ON, No RAM retention, Wake on any event in most of the examples in our SDK. We do have the Real-Time Counter Example which enables the RTC to show you how you control interrupts using the RTC and how to wake from system ON mode using it (System ON, No RAM retention, wake on RTC).

We also have a RAM Retention example to show how to configure the system for RAM retention and trigger system OFF, but this can easily be made out to go to a system ON sleep mode as well. You can implement whatever parts you'd like from these examples to achieve any of the sleep modes you want.

Best regards,

Simon