when power-up NRF52 program does not start until reset

[Ufuk Usta]

The problem is exactly same with the topic. I have custom board for Beacon. At the beginning I soldered 5 boards and all of them was working perfectly. After few days, 4 of them started not to work. I tried to reprogram all and all 4 circuits worked. After that point another problem occurred.

When I powered-down the circuit and powered-up again, program didnt start. I discovered that if i reset the MCU with command line (nrfjprog -f NRF52 --reset) MCU is booting up and starting to advertise. Actually it is not relevent with the reset. I just have to wake up the MCU. For example if I make a "verify" or "read" with nRFgo Studio it also works.

What could be the problem?

By the way I setup 2 more circuit and there is no problem something like that.

The code is almost same with the "eddystone beacon" example. I only added 2 timers for starting and stopping the advertisement. Thats all.

[Ufuk Usta]

Unfortunatelly I cant debug. Maybe i can solder a wire but doing it with a QFN package its really hard. After couple of days, when I repower the devices, they weren't start to advertisement. But its happening only some devices. I exatly dont understand that part. Also, why its not happening with new devices. I am watching some new devices and trying to figure out when its happening.

And problem occurs with the power supply.