We have a product that uses a module containing NR52832 and also both 32kHz and 32MHz crystals. This has been operating correctly and is in full scale production.
On our latest batch of boards we have found that there is a noticable failure rate of these modules whereby 5% of units seemingly run the firmware correctly but there is no BLE transmissions at the point we would expect it.
We have used power profiler and can see the distinctive waveform of the BLE transmission, albeit 5-10% larger.
Using a pickup coil we were able to measure the 32MHz oscillations on a working unit but picked up no such signal on the units that operate but fail to transmit a BLE signal.
I am keen for us to update the firmware to self test for whatever this failure mode is and generate a fault message on our production tester.
I understand the HFCLK gets switched on and off automatically to save power, so I'm not sure which register to use, but wondered if there were a way I could interrogate certain flags to see if the board were working, or use the 2 crystals to verify the presence of one another, and give an approximation of the relationship between the two frequencies.
