GPIOTE rising edge event is not generated with P0.20

[DL_November]

 Hi,

 I'm using nRF52840 DK to construct and test a wireless data transmission system.

 The problem is that I need to detect a 2M Hz clock's rising edge using nRF and it does not work if I use P0.20 as a GPIOTE port.

 I tested the same code with only changing the port to P0.04 or P0.05 and found that everything just works well.

 Is there any predefined usage of P0.20 so that it cannot be used to detect input rising edge?

[ovrebekk]

Hi 

By default P0.20 is connected to the flash memory chip on the DK, and is not available on the pin headers. 

In order to make P0.20 available on the pin header you need to cut solder bridge SD12 and short solder bridge SD22, as described here. 

As a hot tip, if you look on the backside of the DK you can see all the default GPIO assignments, and which solder bridges you need to cut/short in order to make a pin available. 

Best regards
Torbjørn

[DL_November]

As I short the SD22, it works fine. Thanks a lot!

[ovrebekk]

Good to hear that did the trick. I will close the case then