DTS for sensor example using NRF_PSEL fails to build

RE: DTS for sensor example using NRF_PSEL fails to build

Øyvind — Mon, 04 Jul 2022 06:46:05 GMT

No problem at all.

[quote user="maxg"]'m sure I'm not the only NRF learner to make issues for themselves like this but I was having trouble finding similar issues to point me in the right direction.[/quote]

No, you are definitely not the first or the last. It happens to everyone 🙂 There might be more on the issue in nRF5 SDK cases.

RE: DTS for sensor example using NRF_PSEL fails to build

maxg — Fri, 01 Jul 2022 18:02:46 GMT

That makes a lot of sense, and explains the behavior I was seeing with MOSI and the LEDs.

From devboards I've used in the past, my assumption was that "if it's on the headers, it's not bound to anything else and is ready to use", but clearly the NRF52840 DK is more flexible than that (which I think is a really good thing) and I should've perused the documentation for it more carefully.

Appreciate you taking the time to troubleshoot this with me Øyvind, I'm sure I'm not the only NRF learner to make issues for themselves like this but I was having trouble finding similar issues to point me in the right direction.

RE: DTS for sensor example using NRF_PSEL fails to build

Øyvind — Fri, 01 Jul 2022 13:19:26 GMT

[quote user="maxg"]I believe should instead be:[/quote]

Thanks for pointing out. I will forward this information.

[quote user="maxg"]I switched my MOSI to P0.27 and all started to work correctly with the sensor. I have a feeling that the GPIO pins I was trying for MOSI are hooked up to other peripherals on the DK and some interaction there was resulting in the voltage difference on just MOSI, but I'm not 100% sure.[/quote]

Based on the nRF52840DK HW User Guide it seems that you have tried to use the LEDs for SPI communication. Have you disconnected these (If intentionally used)?

Also, P0.17 is connected to the external memory on the DK. To use this pin, please see the Solder Bridge Configuration

This is also visible on the back of the board.

Kind regards,

Øyvind

RE: DTS for sensor example using NRF_PSEL fails to build

maxg — Thu, 30 Jun 2022 18:49:02 GMT

No problem regarding delays, hope your summer vacation goes well.

When I say sensor example, I mean the DTS example outlined here: https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/drivers/pmw3360.html#id4

It uses `SPI_*` (which doesn't resolve) instead of `SPIM_*` for the psels in pinctrl. Please let me know if I'm missing something here. I looked over the changelog briefly and I don't believe this has changed from 1.9.x to 2.x but I could be wrong. I'll update to 2.x.

To be explicit, this (as shown on the docs page):

            psels = <NRF_PSEL(SPI_SCK, 0, 16)>,
                    <NRF_PSEL(SPI_MISO, 0, 15)>,
                    <NRF_PSEL(SPI_MOSI, 0, 17)>;

I believe should instead be:

            psels = <NRF_PSEL(SPIM_SCK, 0, 16)>,
                    <NRF_PSEL(SPIM_MISO, 0, 15)>,
                    <NRF_PSEL(SPIM_MOSI, 0, 17)>;

This is what the sticker says on my DK:

I've had a chance to reference the pinctrl documentation.

I switched my MOSI to P0.27 and all started to work correctly with the sensor. I have a feeling that the GPIO pins I was trying for MOSI are hooked up to other peripherals on the DK and some interaction there was resulting in the voltage difference on just MOSI, but I'm not 100% sure.

If there's any additional insight on this topic that might come to mind for you, please let me know. I'm left wondering if I was doing something fundamentally incorrect with the DK hardware or my configuration (e.g. DTS or code).

RE: DTS for sensor example using NRF_PSEL fails to build

Øyvind — Thu, 30 Jun 2022 08:09:54 GMT

Hi Max,

Due to summer vacation period we might need some time to find the answer to this.

[quote user="maxg"] if the docs need to be updated for the sensor example:[/quote]

What exact sensor sample are you using? Will have the documentation team look into this. Note that there are changes introduces in v2.0.0 compared to v1.9.1. Please see migration note for v2.0.0

[quote user=""]I'm trying to get up and running using the PMW3360 sensor driver (https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/drivers/pmw3360.html) using the NRF52840 DK.[/quote]

What version of the nRF52840DK are you using?

[quote user="maxg"]I believe I actually solved my issue, but I'm wondering if 2.0.0 does this differently or if the docs need to be updated for the sensor example:[/quote]

Have you read through the Pin Control in the nRF documentation?

Kind regards,
Øyvind

RE: DTS for sensor example using NRF_PSEL fails to build

maxg — Thu, 30 Jun 2022 05:23:53 GMT

Hmm, I still can't track this issue down re: low voltage on MOSI. On my scope, MOSI voltage is -400mv to 800mv (1.2v peak-to-peak, but the -400mv is a bit suspect to me) and doesn't trigger at all on my DLA with a threshold voltage of 1.5v.

- I have no pullups/pulldowns on my PMW3360 board for MOSI

- I've tried this pinctrl configuration, same issue:

&pinctrl {
    spi1_default_alt: spi1_default_alt {
        group1 {
            psels = <NRF_PSEL(SPIM_SCK, 0, 16)>,
                    <NRF_PSEL(SPIM_MISO, 0, 15)>;
        };

        group2 {
            psels = <NRF_PSEL(SPIM_MOSI, 0, 19)>;
            bias-pull-up;
            drive-mode = <NRF_DRIVE_H0H1>;
        };
    };

    spi1_sleep_alt: spi1_sleep_alt {
        group1 {
            psels = <NRF_PSEL(SPIM_SCK, 0, 16)>,
                    <NRF_PSEL(SPIM_MISO, 0, 15)>;
            // low-power-enable;
        };
        group2 {
            psels = <NRF_PSEL(SPIM_MOSI, 0, 19)>;
            bias-pull-up;
            drive-mode = <NRF_DRIVE_H0H1>;
            // low-power-enable;
        };
    };
};

- I've tried multiple output pins on the NRF52840 DK for MOSI, each has the same problem

- Checked for shorts to ground or other pins on MOSI, nothing came up

I'm inclined to suspect either an issue with my PMW3360 breakout board (though it's pretty straightforward) or an SPI config issue on my end, but am wondering if there are any suggestions or hints.

RE: DTS for sensor example using NRF_PSEL fails to build

maxg — Thu, 30 Jun 2022 03:50:02 GMT

Hi Øyvind,

I'm using the VS Code extension.

I believe I actually solved my issue, but I'm wondering if 2.0.0 does this differently or if the docs need to be updated for the sensor example:

Instead of `SPI_*` I needed to use `SPIM_*` in the `NRF_PSEL` statements inside the DTS. I found this out here: https://docs.zephyrproject.org/apidoc/latest/nrf-pinctrl_8h.html#a2594557c5e765d65ea7627c5c49e07d6

I'm running into some additional issues with SPI (I can't seem to reliably instrument SPI using my DLA, in particular for the MOSI pin the voltage seems to be low for some reason), but I think my other issue is resolved.

Thanks,

Max

RE: DTS for sensor example using NRF_PSEL fails to build

Øyvind — Wed, 29 Jun 2022 07:55:41 GMT

Hello,

The initial issue that I can see is the difference in nRF Connect SDK versions.

-- Zephyr version: 3.0.99 (/Users/max/Documents/nrfconnect/zephyr)
-- Found dtc: /opt/nordic/ncs/v1.9.1/toolchain/bin/dtc (found suitable version "1.6.1", minimum required is "1.4.6")
-- Found toolchain: gnuarmemb (/opt/nordic/ncs/v1.9.1/toolchain)

Zephyr v3.0.99 is used in the latest version of nRF Connect SDK (v2.0.0), while it's using toolchain from v1.9.1 which is Zephyr v2.7.99.

Are you using VS Code extension or building from command line?

Kind regards,
Øyvind