Key Pin for P3 (SWD) on PCA10004 and PCA10005 different

[jeff]

I just received my nrf51822 dev kit and noticed that the SWD debugging cable will only connect to the PCA10004. The PCA10005 that came with my kit has pin 2 missing, rather than pin 4 (on the PCA10004 board).

I've reviewed both sets of schematics and pc board layouts and, from what I can see, both boards should have the same missing key pin - pin 4 if I'm reading the numbering correctly. Either way, according to the ref docs, they should be the same and mine are not.

So unless I modify the connector, cable or manage some other mod I'm currently unable to use the PCA10005.

I can't imagine that the board was incorrectly assembled, though it's different than any of the reference docs I can find.

Thanks - Jeff

Addition:

Notice that pin 2 (2nd from the top right) is empty, while pin 4 is placed on bare board - no solder pad.

I'm about to unsolder, swap the pin, resolder - but I'd love some guidance on that approach first.

Thanks.

[Håkon Alseth]

Hi Jeff,

Unfortunately, it seems like there has been a mistake in the assembly of that particular module. The missing pin is pin3, which is normally ground. Since there is about 3 other GND pins on the connector, there is an easier fix than to flip the connector.

I can see two alternatives:

1. What you can do is to remove the small plastic "dummy pin" inside the SWD ribbon cable, then connect it to the board.
2. Or simply cut the "floating" pin.

I apologize for any inconvenience, and we will of course provide a replacement if the board is still not working.

Best regards Håkon