Issues building sample LORA send project

RE: Issues building sample LORA send project

runsiv — Mon, 11 Sep 2023 10:56:55 GMT

Hi Lukas

Good to hear your project is compiling

You are correct in regards how you are supposed to wire it. However you are free to changes the pins mostliy as you wish, if you look at this example you can see how to add the pinctrl to your overlay so that you can change the pins used for SPI. If you are using a shield with the radio, you will need to check the shield in regards to correctliy select the pins.

I have attacehd the man page from the linux kernel describing pincotrl. Zephyr also have a documentation https://docs.zephyrproject.org/latest/hardware/pinctrl/index.html explaning the different states with more graphic then the man page.

Regards

Runar

RE: Issues building sample LORA send project

zazas321 — Fri, 08 Sep 2023 17:29:18 GMT

I have managed to solve the issue. It was so silly! I have replaced:
compatible = "nordic,nrf-spim";
with
compatible = "nordic,nrf-spi";

And that fixed the issue. I can now fully build the project without any compilation errors.

I have one more little question that I want to clarify regarding device tree, bindings and properties. My current overlay:

&spi1 {
	compatible = "nordic,nrf-spi";
	status = "okay";
	cs-gpios = <&gpio0 15 GPIO_ACTIVE_LOW>;
	pinctrl-0 = <&spi1_default>;
	pinctrl-1 = <&spi1_sleep>;
	pinctrl-names = "default", "sleep";
	lora0: sx1276@0 {
		compatible = "semtech,sx1276";
		reg = <0>;
		reset-gpios = <&gpio0 13 GPIO_ACTIVE_LOW>;
		dio-gpios = <&gpio0 24 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>,
					<&gpio0 22 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>,
					<&gpio0 17 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>;
		power-amplifier-output = "pa-boost";
		spi-max-frequency = <125000>;
	};
};

/ {
     aliases {
             lora0 = &lora0;
     };
};

I am not fully understanding what does pinctrl-0 and pinctrl-1 mean.

I have opened C::\nrf\v2.4.0\boards\arm\nrf52dk_nrf52832-pinctrl.dtsi and I see the following:

	spi1_default: spi1_default {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 31)>,
				<NRF_PSEL(SPIM_MOSI, 0, 30)>,
				<NRF_PSEL(SPIM_MISO, 0, 29)>;
		};
	};

	spi1_sleep: spi1_sleep {
		group1 {
			psels = <NRF_PSEL(SPIM_SCK, 0, 31)>,
				<NRF_PSEL(SPIM_MOSI, 0, 30)>,
				<NRF_PSEL(SPIM_MISO, 0, 29)>;
			low-power-enable;
		};
	};

Does that mean that for the SPI, I should connect my lora module to the following pins:

SCK - GPIO0 31

MOSI - GPIO0 30

MISO - GPIO0 29

RE: Issues building sample LORA send project

zazas321 — Fri, 08 Sep 2023 15:13:52 GMT

It is not relevant at this point what binding I am trying to use since I am not even trying to physically flash the device at this point. All I am trying to do at this stage is to compile sample lora project for any lora module, it could be sx1276 or even some other lora module. I am just simply trying to confirm if lora send sample project is working.

For the time being, we can assume that I have sx1276 lora module and not sx1278. Lets forget everything I said about sx1278.

Since this is a sample project provided by nRF sdk, and since I barely changed anything apart from adding the following to the overlay,

&spi1 {
	compatible = "nordic,nrf-spim";
	status = "okay";
	cs-gpios = <&gpio0 15 GPIO_ACTIVE_LOW>;
	pinctrl-0 = <&spi1_default>;
	pinctrl-1 = <&spi1_sleep>;
	pinctrl-names = "default", "sleep";
	lora0: sx1276@0 {
		compatible = "semtech,sx1276";
		reg = <0>;
		reset-gpios = <&gpio0 13 GPIO_ACTIVE_LOW>;
		dio-gpios = <&gpio0 24 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>,
					<&gpio0 22 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>,
					<&gpio0 17 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>;
		power-amplifier-output = "pa-boost";
		spi-max-frequency = <125000>;
	};
};

/ {
     aliases {
             lora0 = &lora0;
     };
};

I would expect this to be some kind of small issue that we are not seeing.

Il read through what you have suggested and see what I can do.. I also hope I will be hearing back from you when you had some time to look through this issue. Thank you very much for your time.

RE: Issues building sample LORA send project

runsiv — Fri, 08 Sep 2023 14:19:09 GMT

Hi,

I will look more into the case over the weekend. However the error you see is normally caused by errors in the devicetree, and that is why I wanted to create the correct binding, just to make sure it was not the problem.

The best help I can offer right now is to read this part https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/build/dts/troubleshooting.html

Regards

Runar

RE: Issues building sample LORA send project

zazas321 — Fri, 08 Sep 2023 13:35:21 GMT

Thanks for your response.

I have reverted all changes I have done to C:\nrf\v2.4.0\boards\arm\nrf52dk_nrf52832.dts and added alias to my .overlay instead.

&spi1 {
	compatible = "nordic,nrf-spim";
	status = "okay";
	cs-gpios = <&gpio0 15 GPIO_ACTIVE_LOW>;
	pinctrl-0 = <&spi1_default>;
	pinctrl-1 = <&spi1_sleep>;
	pinctrl-names = "default", "sleep";
	lora0: sx1276@0 {
		compatible = "semtech,sx1276";
		reg = <0>;
		reset-gpios = <&gpio0 13 GPIO_ACTIVE_LOW>;
		dio-gpios = <&gpio0 24 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>,
					<&gpio0 22 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>,
					<&gpio0 17 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>;
		power-amplifier-output = "pa-boost";
		spi-max-frequency = <125000>;
	};
};

/ {
     aliases {
             lora0 = &lora0;
     };
};

Regarding creating device tree binding for sx1278, I dont think it is necessary at this stage of the project but I understand what you are talking about. I aggree it would make more sense to use sx1278 binding if I am using sx1278 hardware. But since changes between sx1278 and sx1276 are minor, I should be able to use sx1276 binding and get it to work with my sx1278 device as a temporary solution.

At this moment, I am more concerned about the other compilation issue I am having that I cannot wrap my head around:

Please could you look at the compilation log that I have added to my initial posted. It complains about :

undefined reference to `__device_dts_ord_107'

I havent managed to find any useful information regarding this particular error.

RE: Issues building sample LORA send project

runsiv — Fri, 08 Sep 2023 11:56:31 GMT

Hi Lukas

Could you revert the changes you have done to :\nrf\v2.4.0\boards\arm\nrf52dk_nrf52832.dts? We don't recommending changing the dts in the zephyr folders and rather use an overlay. This so that other projects are not affected by changes you do for this project.

I had a look through Zephyr's semtech bindings and could unfortuntly not find the 1278. However from the datasheet it looks like the Semtech 1278 is an 1276 with a narrower frequency band. So I would presume that we can use the same driver. So what we then need to do is to create a devicetree binding for the Semtech1278. Here is an simple example created by one of my collauges at support.

1. Create the folders structure dts/bindings inside your application folder

2. Create the filde semtech,sx1278.yaml inside the bindings folder and populated it with the following

description: Semtech SX1278 LoRa Modem

compatible: "semtech,sx1278"

include: semtech,sx127x-base.yaml

3. Update your overlay to use the semtech 1278 radio

Regards

Runar