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  3. voxl_spi_init, failed to open /dev/spidev device: No such file or directory.

voxl_spi_init, failed to open /dev/spidev device: No such file or directory.

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  • Alex KushleyevA Alex Kushleyev

    @이광철 , do you have anything connected to spidev14.0 ? You need a device connected to the spi port.

    If you look at the source code for this test app, it simply tries to ping a specific IMU device, which happens to be installed on board on SPI3 (ICM42688 IMU) : https://gitlab.com/voxl-public/voxl-sdk/core-libs/libqrb5165-io/-/blob/master/apps/examples/qrb5165io-spi-test.c

    So, you should connect your desired device to J10 and modify the example to communicate with your device.

    Also, based on this documentation, https://docs.modalai.com/voxl2-mini-connectors/#j10-pin-out-spi-mode-gpio_67--low-kernel-rebuild-required-to-use, you need to set the GPIO before using:

    voxl-gpio -w 67 1
    

    I hope that helps

    이광철이 Offline
    이광철이 Offline
    이광철
    Contributor
    wrote on last edited by
    #18

    @Alex-Kushleyev

    I will connect my spi device and let you know the results after testing.
    Thanks for your help.

    1 Reply Last reply
    0
    • Alex KushleyevA Alex Kushleyev

      Another quick tip for testing SPI stuff. I found this useful:

      Link Preview Image
      spidev-test/spidev_test.c at master · rm-hull/spidev-test

      Contribute to rm-hull/spidev-test development by creating an account on GitHub.

      favicon

      GitHub (github.com)

      You can download this file to VOXL2, build it using

      gcc -O2 spidev_test.c -o spidev_test
      

      and then you can actually query the IMU on spi 3:

      voxl2-mini:~$ ./spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
      spi mode: 0x0
      bits per word: 8
      max speed: 500000 Hz (500 KHz)
      RX | 00 00 00 47 ...
      

      and from here we know that 0x47 is actually the value WHOAMI register of ICM42688 IMU 🙂

      The data i am sending to the device is 4 bytes used to query the imu, as done here . the value 0xF5 = 0x75 | 0x80 which tells the IMU to send back the value of register 0x75

      이광철이 Offline
      이광철이 Offline
      이광철
      Contributor
      wrote on last edited by
      #19

      @Alex-Kushleyev

      Hi.

      I tested it by connecting my spi device to j10.
      This spi device is working normally in voxl2.
      My program for testing also operates normally with this spi device in voxl2.
      However, when I test the spi device and test program on voxl mini, there is no response to the voxl_spi_write function.

      Also, the test below is the same as before.
      voxl2-mini:/dev$ qrb5165io-spi-test -d 14
      There is no response to the qrb5165io-spi-test -d 14 command.

      I need your help and thanks in advance.

      1 Reply Last reply
      0
      • Alex KushleyevA Alex Kushleyev

        Another quick tip for testing SPI stuff. I found this useful:

        Link Preview Image
        spidev-test/spidev_test.c at master · rm-hull/spidev-test

        Contribute to rm-hull/spidev-test development by creating an account on GitHub.

        favicon

        GitHub (github.com)

        You can download this file to VOXL2, build it using

        gcc -O2 spidev_test.c -o spidev_test
        

        and then you can actually query the IMU on spi 3:

        voxl2-mini:~$ ./spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
        spi mode: 0x0
        bits per word: 8
        max speed: 500000 Hz (500 KHz)
        RX | 00 00 00 47 ...
        

        and from here we know that 0x47 is actually the value WHOAMI register of ICM42688 IMU 🙂

        The data i am sending to the device is 4 bytes used to query the imu, as done here . the value 0xF5 = 0x75 | 0x80 which tells the IMU to send back the value of register 0x75

        이광철이 Offline
        이광철이 Offline
        이광철
        Contributor
        wrote on last edited by
        #20

        @Alex-Kushleyev

        I tested according to your advice.
        This is the result of testing on my mini.

        voxl2-mini:~$ cd /usr/bin
        voxl2-mini:/usr/bin$ spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
        spi mode: 0x0
        bits per word: 8
        max speed: 500000 Hz (500 KHz)
        can't send spi message: Invalid argument
        Aborted

        이광철이 1 Reply Last reply
        0
        • 이광철이 이광철

          @Alex-Kushleyev

          I tested according to your advice.
          This is the result of testing on my mini.

          voxl2-mini:~$ cd /usr/bin
          voxl2-mini:/usr/bin$ spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
          spi mode: 0x0
          bits per word: 8
          max speed: 500000 Hz (500 KHz)
          can't send spi message: Invalid argument
          Aborted

          이광철이 Offline
          이광철이 Offline
          이광철
          Contributor
          wrote on last edited by
          #21

          @이광철

          Alex-Kushleyev sorry.

          voxl2-mini:~$ cd /usr/bin
          voxl2-mini:/usr/bin$ spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
          spi mode: 0x0
          bits per word: 8
          max speed: 500000 Hz (500 KHz)
          can't send spi message: Invalid argument
          Aborted

          This test was my mistake.

          Below are the final test results.
          voxl2-mini:/usr/bin$ spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
          spi mode: 0x0
          bits per word: 8
          max speed: 500000 Hz (500 KHz)
          RX | 00 00 00 47 __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ | ...G

          Alex KushleyevA 1 Reply Last reply
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          • 이광철이 이광철

            @이광철

            Alex-Kushleyev sorry.

            voxl2-mini:~$ cd /usr/bin
            voxl2-mini:/usr/bin$ spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
            spi mode: 0x0
            bits per word: 8
            max speed: 500000 Hz (500 KHz)
            can't send spi message: Invalid argument
            Aborted

            This test was my mistake.

            Below are the final test results.
            voxl2-mini:/usr/bin$ spidev_test -D /dev/spidev3.0 -p "\x76\x00\xF5\x00"
            spi mode: 0x0
            bits per word: 8
            max speed: 500000 Hz (500 KHz)
            RX | 00 00 00 47 __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ | ...G

            Alex KushleyevA Offline
            Alex KushleyevA Offline
            Alex Kushleyev
            ModalAI Team
            wrote on last edited by
            #22

            @이광철 ,

            Please note that qrb5165io-spi-test -d 14 is a test app that just tries to detect a specific IMU on the SPI port. If the specific IMU is not connected, the test will not be successful.

            Are you able to read any data from your SPI sensor (using spidev_test -D /dev/spidev14.0 ... ? Can you share what your sensor is? You should look in the documentation of your sensor and it will tell you how to communicate with it. SPI protocol for reading / writing is specific to the device.

            Also, don't forget about the gpio setting that needs to be made before using SPI 14 (voxl-gpio -w 67 1). this needs to be run after each reboot.

            Alex

            이광철이 1 Reply Last reply
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            • Alex KushleyevA Alex Kushleyev

              @이광철 ,

              Please note that qrb5165io-spi-test -d 14 is a test app that just tries to detect a specific IMU on the SPI port. If the specific IMU is not connected, the test will not be successful.

              Are you able to read any data from your SPI sensor (using spidev_test -D /dev/spidev14.0 ... ? Can you share what your sensor is? You should look in the documentation of your sensor and it will tell you how to communicate with it. SPI protocol for reading / writing is specific to the device.

              Also, don't forget about the gpio setting that needs to be made before using SPI 14 (voxl-gpio -w 67 1). this needs to be run after each reboot.

              Alex

              이광철이 Offline
              이광철이 Offline
              이광철
              Contributor
              wrote on last edited by
              #23

              @Alex-Kushleyev

              Please note that qrb5165io-spi-test -d 14 is a test app that just tries to detect a specific IMU on the SPI port. If the specific IMU is not connected, the test will not be successful.
              Yes I know.

              My spi device and test program works fine on volx2's J10.
              Please refer to j10 in the url below.
              https://docs.px4.io/main/en/flight_controller/modalai_voxl_2.html

              Alex KushleyevA 1 Reply Last reply
              0
              • 이광철이 이광철

                @Alex-Kushleyev

                Please note that qrb5165io-spi-test -d 14 is a test app that just tries to detect a specific IMU on the SPI port. If the specific IMU is not connected, the test will not be successful.
                Yes I know.

                My spi device and test program works fine on volx2's J10.
                Please refer to j10 in the url below.
                https://docs.px4.io/main/en/flight_controller/modalai_voxl_2.html

                Alex KushleyevA Offline
                Alex KushleyevA Offline
                Alex Kushleyev
                ModalAI Team
                wrote on last edited by
                #24

                @이광철 , do you still have any issue? Does spidev_test work with spi 14?

                이광철이 1 Reply Last reply
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                • Alex KushleyevA Alex Kushleyev

                  @이광철 , do you still have any issue? Does spidev_test work with spi 14?

                  이광철이 Offline
                  이광철이 Offline
                  이광철
                  Contributor
                  wrote on last edited by
                  #25

                  @Alex-Kushleyev

                  I tested it by connecting my spi device to j10.
                  This spi device is working normally in voxl2.
                  My program for testing also operates normally with this spi device in voxl2.

                  voxl_spi_init(SPI_BUS, SPI_MODE_0, VOXL_SPI_MAX_SPEED) is OK
                  but, there is no response to the voxl_spi_write function.

                  Alex KushleyevA 1 Reply Last reply
                  0
                  • 이광철이 이광철

                    @Alex-Kushleyev

                    I tested it by connecting my spi device to j10.
                    This spi device is working normally in voxl2.
                    My program for testing also operates normally with this spi device in voxl2.

                    voxl_spi_init(SPI_BUS, SPI_MODE_0, VOXL_SPI_MAX_SPEED) is OK
                    but, there is no response to the voxl_spi_write function.

                    Alex KushleyevA Offline
                    Alex KushleyevA Offline
                    Alex Kushleyev
                    ModalAI Team
                    wrote on last edited by Alex Kushleyev
                    #26

                    @이광철 , can you confirm that you are setting gpio 67 on voxl2 mini before testing spi 14?

                    이광철이 1 Reply Last reply
                    0
                    • Alex KushleyevA Alex Kushleyev

                      @이광철 , can you confirm that you are setting gpio 67 on voxl2 mini before testing spi 14?

                      이광철이 Offline
                      이광철이 Offline
                      이광철
                      Contributor
                      wrote on last edited by
                      #27

                      @Alex-Kushleyev

                      Yes.
                      After executing voxl-gpio -w 67 1, run my test.

                      voxl-gpio -r 67
                      1

                      Alex KushleyevA 1 Reply Last reply
                      0
                      • 이광철이 이광철

                        @Alex-Kushleyev

                        Yes.
                        After executing voxl-gpio -w 67 1, run my test.

                        voxl-gpio -r 67
                        1

                        Alex KushleyevA Offline
                        Alex KushleyevA Offline
                        Alex Kushleyev
                        ModalAI Team
                        wrote on last edited by
                        #28

                        Hmm.. we will investigate.

                        1 Reply Last reply
                        0
                        • modaltbM Offline
                          modaltbM Offline
                          modaltb
                          ModalAI Team
                          wrote on last edited by
                          #29

                          Hi @이광철

                          Sorry for missing guidance, I do think an alias is also needed like this:
                          https://gitlab.com/voxl-public/system-image-build/meta-voxl2-bsp/-/commit/e97a22de6b4e5582fc276a963b958d01a478d56b#999b45d40c8aafd81669d788073c2ea1315dac66_66_62

                          Also for this to work, I believe you will want to use the older devcfg.mbn file as well from SDK 1.0.0 as that has trustzone setup for SPI, and the new devcfg.mbn is setup for UART.

                          If trustzone isn't configured correctly I do think the kernel halts on bootup.

                          Flashing devcfg.mbn is like this, which is likely needed once alias is setup, to convert back to SPI from UART.

                          fastboot flash devcfg_a devcfg.mbn
                          fastboot flash devcfg_b devcfg.mbn

                          이광철이 1 Reply Last reply
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                          • modaltbM modaltb

                            Hi @이광철

                            Sorry for missing guidance, I do think an alias is also needed like this:
                            https://gitlab.com/voxl-public/system-image-build/meta-voxl2-bsp/-/commit/e97a22de6b4e5582fc276a963b958d01a478d56b#999b45d40c8aafd81669d788073c2ea1315dac66_66_62

                            Also for this to work, I believe you will want to use the older devcfg.mbn file as well from SDK 1.0.0 as that has trustzone setup for SPI, and the new devcfg.mbn is setup for UART.

                            If trustzone isn't configured correctly I do think the kernel halts on bootup.

                            Flashing devcfg.mbn is like this, which is likely needed once alias is setup, to convert back to SPI from UART.

                            fastboot flash devcfg_a devcfg.mbn
                            fastboot flash devcfg_b devcfg.mbn

                            이광철이 Offline
                            이광철이 Offline
                            이광철
                            Contributor
                            wrote on last edited by
                            #30

                            @modaltb

                            Hi.
                            I try a test on voxl-mini with your advice applied.
                            voxl-mini sdk version is 1.0.0
                            My program and spi device operates is normal.
                            Thanks for your advice.

                            1 Reply Last reply
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