nRF52810 and its ports

Question

Hello all! 
 looking at the nRF52820 module to develop a BLE mash app, layout, however, I am not sure, are the GPIO ports freely assignable on the nRF or are they fixed? Looking at the QFN40 pckg https://infocenter.nordicsemi.com/index.jsp?topic=%2Fps_nrf52820%2Fpin.html&cp=4_3_0_6_0_0&anchor=wlcsp , 
 I guess certain pins, like SWDIO,SWDCLK and power cannot be moved with the software? BTW what GPIO can be reassigned via software? 
 I am asking this because, it may be easier to design a layout with moving the ports around a bit ... 
 Looking forward to your reply, 
 Best.

Marcel · Answer

Depends on which peripheral drivers you want to use. GPIOs can host almost any peripheral so see the peripheral drivers sections - they will state which ports can be used for specific peripheral functions like SPI, TWI or UART. Some of the functions cannot be moved - such as crystals, JTAG and power pins.