NRF9160 custom board programming issue

[damianogiacomi]

Hi, I have my custom board for the nrf9160 ,

I was able to program it through the built in programmer of the nrf9160 dk but I have an issue, when I connect the VDD to the VDD_GPIO by soldering a bridge the programmer does not recognize the board, where the issue can ? Thanks in advance

[Øyvind]

Hello,

when I connect the VDD to the VDD_GPIO by soldering a bridge the programmer does not recognize the board,

What is VDD_IO (SW11) configured to? It should be configured to 3V to be able to program.

Kind regards,
Øyvind

[damianogiacomi]

 

[Øyvind]

Thanks for the schematic. I am not able to see anything wrong with it. Can you please provide the layout as well? 

Have you measured the voltage on VDD when pin 12 is connected and disconnected? 

[damianogiacomi]

nRF9160_PB.PcbDoc

[damianogiacomi]

Yes there is 3.3v on the vdd

[damianogiacomi]

I don't really know what to check next

[Øyvind]

Thanks for the layout.

You have to redo the ground beneath the nRF9160 SoC. This is not good I'm afraid. You are only grounded through pin 60, and lacking many vias under the module. The rest of the pads are not connected at all to GND. This may be the reason for why you are having issues with your custom board.

This is how is done on the nRF9160 DK


Please follow design rules given in the Schematics and layout for nRF9160DK.

I would also recommend verifying the via hole dimensions with your PCB manufacturer, as they seem somewhat small.

Kind regards,
Øyvind

[damianogiacomi]

Hi ok thanks for the advice, now somehow i menaged to obtain this:

Found Cortex-M33 r0p2, Little endian.
FPUnit: 0 code (BP) slots and 0 literal slots
Security extension: not implemented
CoreSight components:
ROMTbl[0] @ E00FF000
Target connection has been lost

Any hints ;)

[Øyvind]

Where did you get this information? 

What do you get if you run:

nrfjprog -i

One comment I forgot to mention yesterday, is that you need to check the temperature of the SiP. Having only one ground connection will make the device run hot, and this may break it.

Kind regards,
Øyvind

[damianogiacomi]

I am using the segger embedded studio and when I compile the solutin and try to connect the jlink it returns this, sorry for asking but where should I use this command? 

Thanks for the temperature hint I will probably design a different board but I would like to check if what I am doing is correct :)

[damianogiacomi]

The reset pin was not connected right, not it connects but it gives this hardfault exeption in the debugger

[damianogiacomi]

I have a question about what should be the reset pin impedance ?