How to change ble_app_uart example to work without LFCLK?

[Sergio T]

I'm using SDK12 and SES.

I compiled my code based on ble_app_uart example for nRF51822_QFAA and I see in Memory usage that RAM is at correct addresses (finishes at 0x20003FFF). The code runs on PCA10028 but it doesn't run on my target board that has no 32.768kHz oscillator.

I can't find how to put the controller working without LFCLK. Can anyone give a hint?

It is frustrating that I loose 90% of time looking for solutions to put things running rather than coding... very poor documentation about examples cause this!

[Einar Thorsrud]

Hi,

Sergio T said:

And I don't want to know more than what is necessary to make it work.

This is not a good starting point for a successful product. I really recommend you try to learn the basics of the technologies you are using, as that will probably result in a better product.

Sergio T said:

When OFF I need that the controller runs RTC1 with the lowest consumption possible because it will run on a CR2032 battery. Actually quite simple

Yes, it is :) You get this out of the box with the SDK. If you want to wake up and do tasks based on RTC1, then I suggest you use the app timer library. This is a software library that use RTC1 to make an arbitrary number of easy to use low power timers.

 Note that if you disable advertising and disconnect any active BLE connection, then you will in practice have the same current consumption as the case you describe, where you have RTC1 enabled. Therefor I suggest that you avoid "disabling BLE" if that means disabling the SoftDevice. If you mean exactly what I wrote (don't advertise, don't maintain a connection, then that is OK.

[Sergio T]

What is the sequence I should call to disable advertising and disconnect active connection?

[Einar Thorsrud]

You stop advertising by calling sd_ble_gap_adv_stop(). You should only do this if advertising, if not NRF_ERROR_INVALID_STATE will be returned.

Similarly, if you are in a connection, you disconnect by calling sd_ble_gap_disconnect() with the connection handle BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION as disconnect reason. Again, only do this if you are in a connection. If not, an error will be returned.

[Sergio T]

Thanks for the tip: it's working fine.