Hello,
My nRF51822 custome board has problem at first programing software with nRF51 DK. So I checked nRF51822 boot sequence and found diffence compare with nRF51422 which is in dev board.
<Difference with referecence board,nRF51 DK >
- 16MHz crystal is not running in 3.2V VCC input. I found that from Analog input/ouput pin (pin#37 and 38).
- There is not clock in SWCLK pin.
So my question are belows:
- Does 16MHz crystal possible to not running with 3.2V VCC?
- How can I verify QFN part is right soldered in custome board? As I know that can be checked by crystal clock. Anything else?
- Does nRF51822 working with particular 16MHz crystal? I choesed NX2520SA ,NDK, which is already confirmed in dev zone comment.
Of course I followed reference schematic and layout refer with 'QFAC QFN48 schematic with low voltage mode' from spec.
Thanks,
Anton.