App doesn't on custom board

[neves]

Hi, I developed a simple app that connects to a Bluetooth device, receives some data from that device and output it to the uart. As a receiver I have a custom board with a MBN52832. My app works perfectly on the MBN52832DK, but when I load the .hex to my custom board I'm experimenting a strange behavior. My board start advertising and as soon as I turn on the remote device they pair each other. The problem starts when I open a connection with the UART (using TeraTerm)! It enters in an incommunicable state, displaying bunches of error like: "ERROR: Can not read register 0 (R0) while CPU is running" until register 64 and it keeps repeating it until I disconnect TeraTerm!

Using nRF52832_XXAA (PCA10040), SDK14.2, Softdevice 132

What should I look for to solve my problem?

Thanks

[ketiljo]

Does the module have a 32 kHz crystal and your board not? Of so, you must use the RC oscillator instead.

[neves]

Meanwhile I notice that the target voltage on our board is 2.7V in contrast to DK board that is 3.30V. Can this have any influence?

[Håkon Alseth]

Hi,

 

neves said:

Meanwhile I notice that the target voltage on our board is 2.7V in contrast to DK board that is 3.30V. Can this have any influence?

This depends on your programmer used. If you use a programmer that has a "set voltage" (like the nRF5x-DK or the J-Link Lite), normally 3.3V, then it is expected that you might lose the debugger connection, especially if the supply voltage gets a dip. In this case, I recommend powering your board with the exact same voltage as the programmer expects.

What debugger are you using?

 

Best regards,

Håkon

[neves]

Hi,

We are using the J-Link base from Segger.

In a closer look we detected that a different LDO voltage regulator from the original specification was soldiered on the board. So we are waiting for the correct LDO to replace it and continue with the tests.

I'll update this ticket as soon as we have more info.

Thanks,