nreset 0.18 disable

[xuezhi_zed]

I have a customized PCB with nrf52840. Pin 0.18 is used as CS pin in SPI communication. 

I want to disable the nreset function and I add this CONFIG_GPIO_AS_PINRESET=n in .conf file 

When I click flash it still shows 

[ ###### ] 0.000s | Program file - Checking image [ ##### ] 0.000s | Check image validity - Initialize device info [ ########## ] 0.000s | Check image validity - Check region 0 settings [ ############### ] 0.000s | Check image validity - block 1 of 2 [ #################### ] 0.006s | Check image validity - Finished [ ############# ] 0.000s | Program file - Programming [ ########## ] 0.000s | Programming image - block 1 of 1 [ #################### ] 0.000s | Programming image - Write successful [ #################### ] 0.248s | Program file - Done programming
[ ###### ] 0.000s | Verify file - Check image [ ##### ] 0.000s | Check image validity - Initialize device info [ ########## ] 0.000s | Check image validity - Check region 0 settings [ ############### ] 0.115s | Check image validity - block 1 of 2 [ #################### ] 0.006s | Check image validity - Finished [ ############# ] 0.000s | Verify file - Verifying [ ########## ] 0.000s | Verifying image - block 1 of 1 [ #################### ] 0.000s | Verifying image - Verify successful [ #################### ] 0.255s | Verify file - Done verifying
Enabling pin reset.
Applying pin reset.

I read across the platform and I found someone mentioned NCIR and some mentioned system_nrf52840.c but those answers are more than 1 years ago so I am not sure whether those are relevant.

I am using J-LINK for flash and printk though RTT.

What else I need to add after adding CONFIG_GPIO_AS_PINRESET=n ? 

[xuezhi_zed]

Thank you!!!! 

[xuezhi_zed]

Hi Einar, if i disabled the reset correctly, when I press the ifboot/reset button on nrf52840dk , there should be no action right? 

or is there any other method to check if i change 0.18 from reset to a normal GPIO correctly? 

After i done so, it should be able to use as CS pin for spi communication right?

[Einar Thorsrud]

The reset button on the DK is connected to the onboard debugger, and will reset the nRF via the debugger. This is independen of the reset pin on the nRF.

xuezhi_zed said:

or is there any other method to check if i change 0.18 from reset to a normal GPIO correctly? 

The simplest which I use is to connect a jumper wire from P0.18 to GND and release it again (pin reset is active low with an internal pull-up). If that resets the device, pin reset is enabled. If not, it is not enabled.

xuezhi_zed said:

After i done so, it should be able to use as CS pin for spi communication right?

Yes