Matrix keyboard IO select

[LocalHost]

hi，

    I'm use nRF52840 to developing a Computer Keyboard，i wish 8X18 matrix a total of 144 buttons，About keyboard button matrix, please help to determine which GPIO can do keyboard matrix and whether all the following IO can selet to keyboard matrix IO ？

P0.20

P0.02

P1.15

P1.14

P1.13

P1.12

P1.11

P1.10

P0.06

P1.07

P1.06

P1.05

P1.04

P1.03

P1.02

P1.01

P0.03

P0.07

P0.28

P0.29

P0.30

P0.31

P0.08

P1.08

P1.09

P0.19

P0.11

P0.12

[JONATHAN LL]

Hi,


All the Pins that can be used as GPIOS can be used
https://infocenter.nordicsemi.com/topic/ps_nrf52840/gpio.html?cp=4_0_0_5_8 

So all the pins that is listed as General purpose I/O is ok
https://infocenter.nordicsemi.com/topic/ps_nrf52840/pin.html?cp=4_0_0_6_0 


There are some public projects out like the nrfmicro


Regards
Jonathan

[LocalHost]

hi，

    Thank you for your reply，but i see the nRFready Smart Remote 3 nRF52 v1.2.1alpha software，it looks like use gpiote 8 channel to driver 8*8 matrix keyboard，so i use 8*18 matrix the gpiote is it possible to drive ? and software scope of pin is p0.0 to p0.31，do I also use this range pin to convenient software development？

[JONATHAN LL]

Hi,

We only support 8 channels on the nrf52840


We do have a HID Keyboard example, here is the nr5 SDK and here is the NCS version. 


One pin that you might not want to use is the reset pin/P0.18.  If you wan to have the reset function available. 




I do recommend that you star with a nrf52840 DK to test develop the software. 

Regards,
Jonathan