Custom board header file and pin definitions

[hugo_98]

Hi everyone,

I'm new with nordic chips and for our project we use a custom board based on the famous nRF52840 mcu. I read a lot about SDK17 in the infocenter to find how to write my custom board file but I have still some questions. I'm using the arm-gcc "ide" with its lovely makefiles and linker scripts (thank's to Nordic's team for providing it !).

I started by adapting the pca10056.h file since it is about the same MCU and below are my questions :

1. Some pin definitions are done with NRF_GPIO_PIN_MAP macro so you can specify the port number and the pin number (for example it's done for LEDs definition). That's what I would have done for every pin. However some pin definitions are simply the pin number, without the port number and are done without using the NRF_GPIO_PIN_MAP macro (for example the buttons pin definition). Hence my question : why ? I'm afraid creating conflicts if I use the NRF_GPIO_PIN_MAP macro anyway. What should I do ?
2. I a pin is not connected on my custom board but it's connected on the pca10056 dev kit, should I delete the macro or let it defined with no value/a dummy value ?

Regards,

Hugo

[Jared]

Hi,

1. The NRF_GPIO_PIN_MAP() is mostly used in the board file where the pin on PORT 0 has already been defined. This is to not redefine the pin on PORT 0 when you wanted to define the same pin number but on PORT X. You can use NRF_GPIO_PIN_MAP() all the way if you find it confusing (which is understandable). 
2. Probably safest for later development to just have a dummy value. 

regards

Jared

[hugo_98]

Thank you for your reply !

regards

Hugo