Can't read from gpio

RE: Can't read from gpio

Vidar Berg — Tue, 02 Dec 2025 15:25:41 GMT

Hi Keith,

Yes, but the commands must be issued in the correct order.

RE: Can't read from gpio

kruenheck — Tue, 02 Dec 2025 14:53:50 GMT

Vidar,

This is where I got the commands I'm using, but they don't work.

RE: Can't read from gpio

Vidar Berg — Tue, 02 Dec 2025 10:10:39 GMT

Hi Keith,

Please try to apply the configurations before entering shipmode as mentioned in the note here:

RE: Can't read from gpio

kruenheck — Mon, 01 Dec 2025 16:19:23 GMT

Hi Vidar,

using the npm13xx_two_button project, is there a way to have the pmic come out of ship/hold after a longer button press? Right now it comes out on a short press, which I assume is the default.

I tried the following:

WritePmic(SHIP_REGS_MSB, TASKENTERSHIPMODE_LSB, 0x01);

WritePmic(SHIP_REGS_MSB, SHPHLDCONFIG_LSB, 0x07); //0x7=3008ms

ReadPmic(EVENT_MSB, EVENTSVBUSIN0SET_LSB);

WritePmic(SHIP_REGS_MSB, TASKSHPHLDCFGSTROBE_LSB, 0x01); // strobe it

The board comes out of ship mode after a three second button press but immediately turns off again

Thank you,

Keith

RE: Can't read from gpio

kruenheck — Wed, 12 Nov 2025 21:20:38 GMT

Both of your solutions worked. Thank you

RE: Can't read from gpio

Vidar Berg — Wed, 12 Nov 2025 13:26:29 GMT

[quote userid="147730" url="~/f/nordic-q-a/125388/can-t-read-from-gpio/554007"]I tried putting it in cmakelists.txt with set( SHIELD "npm1300_ek"), but that didn't do it. [/quote]

This should work if it's placed before the find_package() line. Instead of including the shiled, you can also define your own board that includes the definitions from the overlay added by this shield:

https://github.com/nrfconnect/sdk-zephyr/blob/main/boards/shields/npm1300_ek/npm1300_ek.overlay

Or create an overlay for your existing build target (nrf52833dk_nrf52833.overlay) that includes the same definition as the npm1300_ek.overlay.

2. For the LED to be controllable it must configured in the host mode here:

The default mode can be selected by changing the overlay here:

Description of the properties from binding:

Best regards,

Vidar

RE: Can't read from gpio

kruenheck — Tue, 11 Nov 2025 16:35:38 GMT

Vidar,

I have two follow up questions:

1. How can I put the extra build command: -DSHIELD=npm1300_ek into a file so it doesn't need to be an extra command? I tried putting it in cmakelists.txt with set( SHIELD "npm1300_ek"), but that didn't do it.

2. How can I blink a different led? The example, npm13xx_two_button blinks ld3 (host) with the commands: led_on(leds, 1U); and led_off(leds, 1U); I tried replacing the 1U with 0U, 2U and 3U, but with those values the leds do nothing.

Thank you

RE: Can't read from gpio

kruenheck — Fri, 07 Nov 2025 16:34:47 GMT

It works now, thank you very much!

RE: Can't read from gpio

Vidar Berg — Fri, 07 Nov 2025 10:15:25 GMT

Hi,

I discussed this issue with one of the developers who pointed out the importance of following the connections outlined in the Wiring section. The jumper placements must be the same as the default placement except for the one on P18 as highlighted below.

Another issue is that I had not enabled the internal pull-up on GPIO2. This can be fixed in the npm1300.overlay:

&npm1300_ek_buttons {
	pmic_button2: pmic_button_2 {
        gpios = < &npm1300_ek_gpio 2 (GPIO_ACTIVE_LOW | GPIO_PULL_UP)>;
	    label = "Pmic button switch 2";
		zephyr,code = <INPUT_KEY_2>;
	};
};

We will look into adding a picture of the EK with the correct jumper placements for this sample.

Best regards,

Vidar

RE: Can't read from gpio

kruenheck — Thu, 06 Nov 2025 17:50:30 GMT

Vidar,

I upgraded to 3.1.1 and the code builds. It also runs but not very well. When it boots up, it says: Button state (PMIC GPIO2): pressed. I'm surprised by GPIO2 because I'm connected to GPIO3 on the pmic. Also, your screenshot says 'released' on bootup while mine says 'pressed'.

In addition, I have the following issues:

1. I see 'led device not ready' errors quite frequently. The fix seems to be power-cycling the pmic. I haven't put a scope on the i2c lines, but they should be ok because my other apps work.

2. It takes a long time between button presses and any activity in the software. Sometimes I get nothing, and other times I'll get 'Short press' after many seconds (like half a minute).

3. I never see 'switched 4 pressed'. It always says 'Short press', no matter how long I press the button.

Any ideas as to what's going on?

Thank you

RE: Can't read from gpio

Vidar Berg — Wed, 05 Nov 2025 21:36:35 GMT

Sorry, I forgot to specify that I was testing against nrf connect sdk version 3.1.x and there looks to be some naming changes between these 2 sdk releases. Are you able to try with this SDK version too? I can also backport my changes if needed.

RE: Can't read from gpio

kruenheck — Wed, 05 Nov 2025 21:10:22 GMT

Vidar,

Thank you for the effort you put into this, but I can't seem to build what you sent me. In npm1300.overlay, I needed to change

#include <dt-bindings/regulator/npm13xx.h>

to
#include <dt-bindings/regulator/npm1300.h>

But now I'm getting another error in npm1300.overlay. Here's the output:

-- west build: generating a build system
Loading Zephyr default modules (Zephyr base).
-- Application: C:/myNordic/fromDevZone/npm13xx_two_button
-- CMake version: 3.21.0
-- Found Python3: C:/ncs/toolchains/0b393f9e1b/opt/bin/python.exe (found suitable version "3.12.4", minimum required is "3.10") found components: Interpreter
-- Cache files will be written to: C:/ncs/v3.0.2/zephyr/.cache
-- Zephyr version: 4.0.99 (C:/ncs/v3.0.2/zephyr)
-- Found west (found suitable version "1.2.0", minimum required is "0.14.0")
-- Board: nrf52833dk, qualifiers: nrf52833
-- Found host-tools: zephyr 0.17.0 (C:/ncs/toolchains/0b393f9e1b/opt/zephyr-sdk)
-- Found toolchain: zephyr 0.17.0 (C:/ncs/toolchains/0b393f9e1b/opt/zephyr-sdk)
-- Found Dtc: C:/ncs/toolchains/0b393f9e1b/opt/bin/dtc.exe (found suitable version "1.4.7", minimum required is "1.4.6")
-- Found BOARD.dts: C:/ncs/v3.0.2/zephyr/boards/nordic/nrf52833dk/nrf52833dk_nrf52833.dts
-- Found devicetree overlay: npm1300.overlay
devicetree error: ./npm1300.overlay:10 (column 1): parse error: undefined node label 'npm1300_ek_ldo1'
CMake Error at C:/ncs/v3.0.2/zephyr/cmake/modules/dts.cmake:305 (execute_process):
execute_process failed command indexes:

1: "Child return code: 1"

Call Stack (most recent call first):
C:/ncs/v3.0.2/zephyr/cmake/modules/zephyr_default.cmake:133 (include)
C:/ncs/v3.0.2/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:66 (include)
C:/ncs/v3.0.2/zephyr/share/zephyr-package/cmake/ZephyrConfig.cmake:92 (include_boilerplate)
CMakeLists.txt:8 (find_package)

-- Configuring incomplete, errors occurred!
←[91mFATAL ERROR: command exited with status 1: 'C:\ncs\toolchains\0b393f9e1b\opt\bin\cmake.EXE' -DWEST_PYTHON=C:/ncs/toolchains/0b393f9e1b/opt/bin/python.exe '-Bc:\myNordic\fromDevZone\npm13xx_two_bu
tton\build' -GNinja -DBOARD=nrf52833dk/nrf52833 -DEXTRA_DTC_OVERLAY_FILE=npm1300.overlay '-Sc:\myNordic\fromDevZone\npm13xx_two_button'
←[0m
* The terminal process terminated with exit code: 1.
* Terminal will be reused by tasks, press any key to close it.

Thank you

RE: Can't read from gpio

Vidar Berg — Wed, 05 Nov 2025 16:48:23 GMT

Hi,

Please try the modified version of this sample that I’ve included below. The zip also includes the changes I made (a diff), screenshot of build configuration and expected log output, and the hex file from my build.

devzone.nordicsemi.com/.../npm13xx_5F00_two_5F00_button.zip

Note: it seems that sometimes after power up, you have to press Button 3 on the DK first before it can detect any GPIO events from the PMIC. I’ll discuss this issue with the developers.

RE: Can't read from gpio

kruenheck — Tue, 04 Nov 2025 16:59:20 GMT

Vidar,

I don't know what I'm supposed to do with a PMIC GPIO driver/shim.

I tried the npm13xx_one_button sample, but I'm not seeing the callback event (I put a printk() in

event_callback()).

I'm not testing the battery at this point, just trying to see a button, so I didn't set any of the jumpers mentioned in the readMe. But I did make the following connections:

SDA	P0.26
SCL	P0.27
GPIO3	P0.04
VDDIO	VDD
GND	GND

Without adding the npm1300.overlay or the Extra CMake argument, I see "PMIC device ok" (but no call back). However, when I add either the overlay or the cmake argument, I get "Error: led device is not ready"

I'm not sure where to go from here

RE: Can't read from gpio

Vidar Berg — Tue, 04 Nov 2025 13:42:26 GMT

Hello,

I did not get around to testing this today, but we have a sample demonstrating how you can use the Zephyr GPIO driver API with the PMIC here: https://docs.nordicsemi.com/bundle/ncs-latest/page/nrf/samples/pmic/native/npm13xx_one_button/README.html. Have you tried this already?

The PMIC GPIO driver/shim can be found here: https://github.com/nrfconnect/sdk-zephyr/blob/main/drivers/gpio/gpio_npm13xx.c

Best regards,

Vidar