NCS 1.9.99: How to set sda and scl pins for I2C

RE: NCS 1.9.99: How to set sda and scl pins for I2C

Jan_Erik — Thu, 12 May 2022 20:58:06 GMT

Thanks, Øivind. I followed your suggestion of putting the pinctrl-* fields outside of the sht3xd block. I also needed to specify the pin numbers using the new convention instead of the old. In the old system port 1, pin 13 was pin 45 and port 1, pin 15 was pin 47 (pin was specified as pin number plus 0 for port 0 or plus 32 for port 1). Under pinctrl, the port and pin are separated so port 1, pin 13 should be specified as <NRF_PSEL(TWIM_SDA, 1, 13)> not <NRF_PSEL(TWIM_SDA, 0, 45)>. You know all this, I'm just elaborating for someone else who might stumble upon this thread.

The v1.9.99 SHT3XD sample now builds and runs correctly for me on the nrf52840dk with my target pins.

I added nrf52840dk_nrf52840.overlay to the boards directory:

&pinctrl {
   i2c0_default_alt: i2c0_default_alt {
      group1 {
         psels = <NRF_PSEL(TWIM_SDA, 1, 13)>,
                 <NRF_PSEL(TWIM_SCL, 1, 15)>;
      };
   };
   i2c0_sleep_alt: i2c0_sleep_alt {
      group1 {
         psels = <NRF_PSEL(TWIM_SDA, 1, 13)>,
                 <NRF_PSEL(TWIM_SCL, 1, 15)>;
         low-power-enable;
      };
   };
};

&i2c0 {
    pinctrl-0 = <&i2c0_default_alt>;
    pinctrl-1 = <&i2c0_sleep_alt>;
    pinctrl-names = "default", "sleep";
	sht3xd: sht3xd@45 {
        status = "okay";
		compatible = "sensirion,sht3xd";
		reg = <0x45>;
		label = "SHT3XD";
		alert-gpios = <&gpio1 10 GPIO_ACTIVE_HIGH>;
	};
};

I also made two changes to the main.c file:

14d13
< #define SHT3XD DT_NODELABEL(sht3xd)
29c28
< 	const struct device *dev = DEVICE_DT_GET(SHT3XD);
---
> 	const struct device *dev = device_get_binding("SHT3XD");

RE: NCS 1.9.99: How to set sda and scl pins for I2C

Øivind — Thu, 12 May 2022 11:56:53 GMT

Try putting the pinctrl-* fields outside of the sht3xd block. If that doesn't work, there should be a file at build/zephyr/include/generated called devicetree_unfixed.dts. Attach that here with Insert->Image/video/file and I'll take a look.

Ok, so that's why you are looking into 1.9.99, makes sense. Make a ticket specifically for the openthread issues if you are unable to solve them, and we will do our best to assist you.

RE: NCS 1.9.99: How to set sda and scl pins for I2C

Jan_Erik — Thu, 12 May 2022 02:03:03 GMT

Hi,

I'm developing an environmental control system using openthread and zephyr COAP. The system works but intermittently the openthread connection detaches, then becomes leader, but won't rejoin the existing network. This will be challenging to debug as I haven't found a way to trigger the problem. As a first step in trouble shooting I wanted to use more recent versions of the libraries to see if the problem persists. I chose 1.9.99 since it will have the most recent versions of zephyr, openthread, and COAP.

As you point out, the way pins are set was changed to pinctrl. I was able to get the sht3xd example to compile with this overlay below but it doesn't connect with the device. I'll see if my original problem is solved with v1.9.1

&pinctrl {
   i2c0_default_alt: i2c0_default_alt {
      group1 {
         psels = <NRF_PSEL(TWIM_SDA, 0, 45)>,
                 <NRF_PSEL(TWIM_SCL, 0, 47)>;
      };
   };
   i2c0_sleep_alt: i2c0_sleep_alt {
      group1 {
         psels = <NRF_PSEL(TWIM_SDA, 0, 45)>,
                 <NRF_PSEL(TWIM_SCL, 0, 47)>;
         low-power-enable;
      };
   };
};

&i2c0 {
	sht3xd@45 {
        status = "okay";
		compatible = "sensirion,sht3xd";
        pinctrl-0 = <&i2c0_default_alt>;
        pinctrl-1 = <&i2c0_sleep_alt>;
        pinctrl-names = "default", "sleep";
		reg = <0x45>;
		label = "SHT3XD";
		alert-gpios = <&gpio1 10 GPIO_ACTIVE_HIGH>;
	};
};

RE: NCS 1.9.99: How to set sda and scl pins for I2C

Øivind — Wed, 11 May 2022 15:30:12 GMT

Hi,

The way pins are set has been changed for future releases, and this change is present on the devtag 1.9.99.

Is there a reason that you are using 1.9.99, and not 1.9.1?
On 1.9.1 you would not see these errors.

RE: NCS 1.9.99: How to set sda and scl pins for I2C

yoyou — Wed, 11 May 2022 06:35:16 GMT

Hi,

please try:

check the entire overlay file for blue line conflicts

remove build, and add new

Best regards