nRF51822 bonding failed

RE: nRF51822 bonding failed

Yi Su — Mon, 07 Apr 2014 22:47:55 GMT

Hi Hung Bui,

Thank you for your suggestion. It seems the 32kHz crystal is not working properly in my custom board. I tried to use the 32kHz RC, and the board bonded and was able to transmitting data.

RE: nRF51822 bonding failed

Hung Bui — Mon, 07 Apr 2014 09:11:58 GMT

Hi YiSu,

Have you tried to use the 32kHz RC instead of the 32kHz crystal ?(by using for example NRF_CLOCK_LFCLKSRC_RC_250_PPM_4000MS_CALIBRATION in SOFTDEVICE_HANDLER_INIT())

Could you send me a close up photo of your board ? Have you tried with our stock SDK example or only with your firmware ? Could you try with other example, such as ble_app_hrs.

Do you have the same issue all the time when using Master Control Panel ?(connection BTLE_CONN_FAILED_TO_BE_ESTABLISHED )

RE: nRF51822 bonding failed

Yi Su — Fri, 04 Apr 2014 22:00:19 GMT

Thank you for the quick response. After I posted this question, I found an older post with the same problem and he solved the problem. According to your answer in that post, I noticed the load capacitance for both crystal are not proper. I use 425F35B016M0000(CTX804CT-ND) for 16MHz crystal and ABS07-32.768KHz-T(535-9542-1-ND) for 32kHz crystal. I calculated the right load capacitance should be: 22pF for 16MHz and 21pF for 32kHz. But I need to order those capacitors so I tried first with replace the 16MHz crystal with one in the development board. But it still couldn't bond. Now I don't know if it is the same problem with the older post.

RE: nRF51822 bonding failed

Hung Bui — Fri, 04 Apr 2014 13:16:46 GMT

Hi YiSu,

Could you try using the nRF Master Control Panel for testing ? There is a log file that might be useful to find the issue.

Your antenna might not be tuned and may limit the range of the RF.

Could you send me know the 16MHz crystal you use on your custom board ?