How to verify that the 32MHZ crystal is actually working (nRF52832?

[abdosalm]

I am using nRF connect SDK v2.9.0 with a custom developed board that looks like this:

I tried the 'Bluetooth LE LED Button service' sample as it's and noticed that nothing was working. I grapped my logic analyzer and hooked it up onto the 32MHZ but nothing is showing. I mean other functionalities like zepyrRTOS, PWM, GPIOs, I2C, etc...  are working successfully but not BLE.

does the nRF52832 have an internal clock through which it works by default and if so, how does it use the external clock. what is the first thing to debug?

this is the crystal I am using:

https://www.lcsc.com/product-detail/Crystals_YXC-Crystal-Oscillators-X322532MOB4SI_C9009.html 

and these are the schematics:

[JONATHAN LL]

You would need a DK or a dongle, but if you have something else that can measure Bluetooth RSSI then that might also work. But the nRF52840 USB Dongle will also do the trick. 

Regards,
Jonathan

[abdosalm]

I am afraid I don't have anything that can measure Bluetooth RSSI currently, I have access to a SA and VNA but using those will have to wait until UFL connectors arrive. Currently, I am waiting for the nRF52840 USB Dongle to arrive and I will keep you posted regarding my problem once I receive that dongle. 

Thanks a lot and sorry for any disturbance I may have caused.

[JONATHAN LL]

abdosalm said:

I have access to a SA and VNA but using those will have to wait until UFL connectors arrive.

This is the best to use, you could connect a normal 2.4GHz antenna to the Spectrum Analyzer and see as well. Or wait for the connector. 


We often end up soldering directly on to the RF path with a coax cable and connect that to the  Spectrum Analyzer to check how well the radio preforms. If you have something similar then that will do as well. 

Regards,
Jonathan

[Turbo J]

Broken antenna or connector only reduces the range to less than about 1m.

If you have sender and receiver close together you should still be able to get a connection working, BTDT.

It just won't work across the room, and can be very directional.

[abdosalm]

I have made the tests that were discussed before, I downloaded the .hex file you provided to me before and here are the results:

This is the output of the ANT pin on the spectrum analyzer without being connected to the Antenna or the matching network:

As you can see, there is a peak at 2.44 GHZ. I then used the nRF52840 USB dongle as an RSSI viewer, and here are the results:

Before powering the MCU:

After powering the MCU, where both of the boards are placed closely together:

There is a clear peak at 2.4 GHZ.

 

Nevertheless, when I programmed the MCU with the Bluetooth sample example,, the mobile app doesn't detect the presence of any Bluetooth devices:

I have this mobile app with another MCU vendor for Bluetooth connectivity (BLE 5.3), and it worked successfully, so I don't think it's the mobile app but rather the code. I can't seem to know what's wrong with the code. I am using the 32 KHZ crystal oscillator that's required by the example code. All of the functions being called in the code doesn't return any errors.