RC Oscilator with SDK 2.8.0

[FrankBajahr]

Hello Nordic team,

just received my first hardware and try to port my code which I developed by using the 54L15PDK board with SDK 2.7.0. At the PDK everything did run fine. 

When flashing the code to my hardware it seems that everything works out well, except the BT doesn´t work at all. As I got a hint to use the new 2.8.0 SDK for the latest chip iteration I was about to do so. However, when compiling the code previously developed for the 54L15PDK I get:

opt/nordic/ncs/v2.8.0/zephyr/drivers/timer/nrf_grtc_timer.c: In function 'sys_clock_driver_init':
/opt/nordic/ncs/v2.8.0/zephyr/drivers/timer/nrf_grtc_timer.c:511:36: error: 'NRF_GRTC_CLKSEL_LFLPRC' undeclared (first use in this function); did you mean 'NRF_GRTC_CLKSEL_LFCLK'?
511 | nrfx_grtc_clock_source_set(NRF_GRTC_CLKSEL_LFLPRC);
| ^~~~~~~~~~~~~~~~~~~~~~
| NRF_GRTC_CLKSEL_LFCLK
/opt/nordic/ncs/v2.8.0/zephyr/drivers/timer/nrf_grtc_timer.c:511:36: note: each undeclared identifier is reported only once for each function it appears in

We are using the LFCLK-PINS as GPIO. So I did the following configurations:

CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y

CONFIG_CLOCK_CONTROL_NRF_K32SRC_500PPM=y

CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC_CALIBRATION=y

CONFIG_CLOCK_CONTROL_NRF_CALIBRATION_LF_ALWAYS_ON=y

Any idea what has changed in the 2.8.0 not to work with the internal RC anymore? Is it really required to change to 2.8.0 to get the BT running?

The chip does show the following laser engraving: 54L15, QFAABB, 2435AB 

Well, as usual, any hints are welcome.

Best regards

Frank

[Einar Thorsrud]

Hi,

Which version of the development board do you have? If it is version 0.8.1 or higher, it is a DK even if it says "PDK" on the box. And if so, SDK 2.8.0 will work. Bu but if it has a lower version you need to obtain a DK, as the PDK only works with previosu versions. You will need to select the DK build target (not the PDK, which is no longer supported).

[FrankBajahr]

Hello Einar,

the development board I´m using is a PCA10156 0.7.0. 

I disconnected the 32kHz crystal on that PDK board and BT is running as it it supposed to be. I´m using SDK 2.7.0

When porting the software to my custom board I have been using the same source code as for the demo board. BT did not show up. Could be a hardware issue on the demo board too. So I was hoping that the new SDK 2.8.0 would do the job for me, but instead it was always giving me the above error pointing to the LF-clock.

Well, is there any easy way to send a CW out which would allow me to see a signal at the spectrum analyser? Maybe it's really a hardware issue?

Any hints are welcome.

Best regards

Frank 

[Einar Thorsrud]

Hi Frank,

FrankBajahr said:

the development board I´m using is a PCA10156 0.7.0.

I see. That has an Engineering A SoC on it, and that is no longer supported in SDK 2.8.0 so it expected that this does not work. I would recomend that you stop using it an obtain a DK that can be used with current and future SDK releases.

FrankBajahr said:

Well, is there any easy way to send a CW out which would allow me to see a signal at the spectrum analyser?

Yes, you can use the Radio test to set up a constant carrier. The sample can be used as is on custom HW, but you need to adjust the UART pins to pins that are available on your device, and set the clock config appropriately (and the same with DCDC if your custom board does not have that).

[FrankBajahr]

Hello Einar,

understand all of it, but that gets me back to the initial question of why I´m having issues on getting my code to work when using the configuration for the internal RC as the LF clock? I do have those issues only when using the 2.8.0 SDK. As mentioned, it used to work fine when using 2.7.0 and the PDK. 

I used the "radio-test" example before on nrf connect sdk and a 52832. However, I haven´t found it In the samples of the 2.7.0/2.8.0 SDK. Anyway, I guess the root cause of all my problems seems to be to get that 2.8.0 to work. 

Thank´s for your patience and best regards

Frank