IO output voltage during flash firmware using Jlink.

[Anthony Yuan]

Hi,

My custom board using P0.23 as a PWM output to control a PWM fan. It works properly when the firmware is running.

But I noticed that when flash firmware using JLink (west flash -> nrfjprog), the pwm fan start to rotate. And I check the voltage of P0.23 and it output around 0.2 volt.

Is there a way to set IOs not output voltage/current during program firmware?

My firmware is based on NCS 2.2.0.

Regards,

Anthony Yuan 

[Sigurd]

Hi,

If you do nrfjrpog --eraseall, do you measure 0.2V at P0.23 ?

[Anthony Yuan]

Hi Sigurd，

On my custom board, when nrfjprog --eraseall, measure 0.1V @ P0.23 and 0.2V @ P0.25

And I measure 52840DK when nrfjprog --eraseall, measure 0V @ P0.23 and 0.2V @ P0.25

Regards,

Anthony

[Sigurd]

Is there a way to set IOs not output voltage/current during program firmware?

I don't see any ways to change this. The default value of the pin is floating( PIN_CNF[n]) , so you might see that the value is a bit higher than 0V.