Issue when programming NRF52840 dongle with DK and segger

[campestring]

Hello everyone I am trying to program my dongle with the Dk Following this schematic : 

When I press the reset button on the dongle, the led start pulsing in red.

I am trying to run the ble blinky example for dongle and when I click on start debug I have this window : 

And after few seconds this second one with the error  : 

And then my dongle stop pulsing red and need to be reset.

THank you and have a good day ! 

Arnaud

[haakonsh]

How did you connect to the dongle? Via the 10-pin tag-connect, 10-pin j-link , or directly to VDD, GND, SWDCLK, and SWDIO? 

Was the dongle connected via USB while programming? 

[campestring]

the dongle isn't connected to usb, I directly connected to the pin on the schematics, so directly to VDD, GND,SWDCLK and SWDIO.

[haakonsh]

Can you share a picture of how you've wired it up?

[campestring]

Yes ! 

[haakonsh]

I think you're missing the ground connection, GND_DETECT is not actually ground, but an input pin to the debugger to check for the presence of an external device. i.e if GND_DETECT is pulled low there's an external device connected.

You need another jumper wire from dongle ground to DK ground.

-edit:
It also looks like your VDD jumper is connected to GND on your breadboard, move it over to VDD_OUT.

[campestring]

THe gnd_detect is a black wire on the picture it's difficult to see it but it's here. and my VDD jumper goes on the Vbus not on the VDD_Out.

[haakonsh]

haakonsh said:

I think you're missing the ground connection, GND_DETECT is not actually ground, but an input pin to the debugger to check for the presence of an external device. i.e if GND_DETECT is pulled low there's an external device connected.

campestring said:

He gnd_detect is a black wire on the picture it's difficult to see it but it's here.

 I know, read my statement again.

You need to connect to VDD_OUT, not VBUS. Otherwise, the two devices won't have the same logic levels. 

[campestring]

But gnd_detect is pulled low with the green wire connect to the gnd of the Dk, I have change the connexion from vbus to vdd out, I can start the debug but the led continue to pulse red and the Dongle isn't programmed.

[campestring]

It works for the blinky example at least, but I can't upload the ble_blinky example... the led pulse red...