Can't read from gpio

[kruenheck]

Trying to read button 3 on the npm1300-ek, which is gpio 1 according to the schematic. The following #defines represent the gpio related registers on the npm1300:

#define GPIOS_MSB         0x06                     // GPIO registers MSB=0x600, individual registers below are added to this 

#define GPIO_MODE1      0x01                     // mode for gpio one (pin)

#define GPIO_STATUS_LOWER    0x1e       // gpio status (all five pins)

I verified that gpio 1 is set to an input using the following:

uint8_t regsy[] = {GPIOS_MSB, GPIO_MODE1};                            

ret = i2c_write_read_dt(&dev_i2c_pmic, regsy, 2, &valRead, 1); 

valRead came back zero indicating to me that the pin is an input

But when I press the button and read the inputs with the following:

uint8_t regsy[] = {GPIOS_MSB, GPIO_STATUS_LOWER};                            

ret = i2c_write_read_dt(&dev_i2c_pmic, regsy, 2, &valRead, 1); 

valRead comes back zero, indicating that the button hasn't affected the pin (it's also zero when the button isn't pressed)

Note that I can perform a write/read to an adc register and get the correct value back, so i2c should be working.

What am I missing?

[Vidar Berg]

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

[kruenheck]

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

[Vidar Berg]

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. 

[kruenheck]

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

[Vidar Berg]

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

[kruenheck]

It works now, thank you very much!

[kruenheck]

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

[Vidar Berg]

1.

kruenheck said:

I tried putting it in cmakelists.txt with set( SHIELD "npm1300_ek"), but that didn't do it. 

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

[kruenheck]

Both of your solutions worked. Thank you

[kruenheck]

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

[Vidar Berg]

Hi Keith,

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

[kruenheck]

Vidar,

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