can we over-write the pins in the nrf52840?

[daman_kaur86]

i am using nrf52840 DK. We have dedicated pins for say QSPI, UART, etc. but if I want to connect external flash memory i.e W25Q16 to the board, to which pins I should connect the external flash memory? do we have to connect to the same pins which are dedicated for the qspi on board??

[Karl Ylvisaker]

Hello,

The nRF52840 DK already has a 64 MB external memory on board, connected to the SoC with QSPI.
You may very well disconnect this memory, and instead use the pins as either regular GPIOs or QSPI pins to another module, as described in the documentation.
Keep in mind that the nRF52840 only has a single QSPI instance, so if you are going to add more QSPI modules ( more than 1 ) they will have to be on the same bus.

do we have to connect to the same pins which are dedicated for the qspi on board??

No, you may use whichever GPIO's you would like for this. However, you will need to make sure that the pins are not designated as "low-frequency I/O"( < 10kHz ) in the pin assignment - this is because the pins are located close to the radio, and high frequency signals on these pins might therefore interfere with the radio, degrading radio performance.

Please do not hesitate to ask if anything should be unclear, or if you encounter any other issues or questions!

Best regards,
Karl