Can't detect the custom device after uploading ble_app_beacon example (nRF52810)

[mertklic]

Hi,

I developed a custom board with nRF52810. Here is my schematic: 

Layout:

I can succesfully upload the "ble_app_beacon" example in SDK17.1.0 with softdevice112 using Segger Embedded Studio.

I power my device with STLink and use JTAG to program it. I connected the GND of STLink and JTAG to achive this. 

I can debug too.

Dont mind the commented lines. I tried to toggle a LED in order to make sure that i can program the device correctly and it worked.

The problem is device is not detectable. I dont think the BLE works properly. Here is my setup. I connected an external 2.4GHz antenna in case my PCB antenna is not good.

I dont know what to do. 

Any help would be great.

Regards,

Mert 

[mertklic]

Hi Håkon,

For now I only have a xtal with CL of 12pF. I bought a new one and waiting for it to replace.

I ran the same project with new code included and there was no problem. The beacon still works without getting stuck at while loop.

But when i observe the crystal with my oscilloscope, i still dont see any clock signal.

the breakpoint also works.

I made some research and seems like it is good to have lf crystal to save power.

Why do you think i dont see any signal on oscilloscope?

Regards,

Mert

[Håkon Alseth]

Hi,

 

If the firmware is not stuck in the loop, and your BT link works, the LFCLK is setup correctly.

SoftDevice has a dependency on the LFCLK as well as the HFXO, so without those it will not advertise.

mertklic said:

But when i observe the crystal with my oscilloscope, i still dont see any clock signal.

Loading the xtal with a probe will highly likely change the amplitude of the signal, so it will go down to < 100 mVpp.

 

Setup a app_timer instance, with a known interval, and toggle a pin in the handler instead. This will give you a indicator of the accuracy of the LFCLK.

 

Kind regards,

Håkon

[mertklic]

Hi Håkon

Thank you for your help. I solved all my problems.

Regards,

Mert