# jetson tx2 spidev

**URL:** <https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215>\
**Category:** Jetson TX2\
**Created:** [October 14, 2019, 7:24am UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215 "2019-10-14T07:24:36Z")\
**Posts on this page:** 11\
**Page:** 1

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**Author:** ![qinyyuu](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/qinyyuu/32/11223_2.png) [@qinyyuu](https://forums.developer.nvidia.com/u/qinyyuu)\
**Post date:** [October 14, 2019, 7:24am UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215/1 "2019-10-14T07:24:36Z")

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the jetson tx2 L4T version ：R32.2.1

the spi pins ：  
SPI1\_CLK G13  
SPI1\_MISO F14  
SPI1\_MOSI F13  
SPI1\_CS0 E13

my devicetree node is :

```auto
spi@3240000 {
    spi_qy@0 {
        compatible = "spidev";
                        reg = <0x0>;
                        spi-max-frequency = <0x1312d00>;
                        nvidia,enable-hw-based-cs;
                        nvidia,cs-setup-clk-count = <0x1e>;
                        nvidia,cs-hold-clk-count = <0x1e>;
                        nvidia,rx-clk-tap-delay = <0x1f>;
                        nvidia,tx-clk-tap-delay = <0x0>;

    }
}

```

while I’m runing ./spidev\_test -D /dev/spidev3.0

the RX is 00 00 00…  
the ture should be FF FF …

at the L4T R28.2.1 the function is usefull.the hardware is well .

what should I do ? thanks

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**Author:** ![ShaneCCC](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/shaneccc/32/14043_2.png) [@ShaneCCC](https://forums.developer.nvidia.com/u/ShaneCCC)\
**Post date:** [October 14, 2019, 8:01am UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215/2 "2019-10-14T08:01:21Z")

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Have a reference to below topic.

> **[SPI1 not work on Xavier](https://forums.developer.nvidia.com/default/topic/1049170)**
>
> I enable the spi1 and add spidev device node in dts. I can find the /dev/spidev0.0, but I can’t detect the signal with Logical Analysis. So, I want to know that the SPI1 is spidev0.0, right ?

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<div class="post-metadata">

**Author:** ![qinyyuu](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/qinyyuu/32/11223_2.png) [@qinyyuu](https://forums.developer.nvidia.com/u/qinyyuu)\
**Post date:** [October 15, 2019, 2:01am UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215/3 "2019-10-15T02:01:14Z")

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hi ShaneCCC，  
in the topic,we can see it’s solved by modifying the pinmux file.and the device is jetson xavier.

I saw the jetson tx2 in the bootloader/t186ref/BCT have the file,but I don’t know which one and what should I do to modify.

in the net ,most of the solution is to modify the device tree.This way I can not refresh the system.

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<div class="post-metadata">

**Author:** ![ShaneCCC](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/shaneccc/32/14043_2.png) [@ShaneCCC](https://forums.developer.nvidia.com/u/ShaneCCC)\
**Post date:** [October 15, 2019, 3:24am UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215/4 "2019-10-15T03:24:03Z")

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Have a reference to below link.

[https://devtalk.nvidia.com/default/topic/1056610/jetson-tx2/spi-config-on-tx2-r28-3/post/5357387/#5357387](https://devtalk.nvidia.com/default/topic/1056610/jetson-tx2/spi-config-on-tx2-r28-3/post/5357387/#5357387)

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<div class="post-metadata">

**Author:** ![qinyyuu](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/qinyyuu/32/11223_2.png) [@qinyyuu](https://forums.developer.nvidia.com/u/qinyyuu)\
**Post date:** [October 15, 2019, 3:54am UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215/5 "2019-10-15T03:54:14Z")

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what should I do to update the tegra186-mb1-bct-pinmux-quill-p3310-1000-c03.cfg file?

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<div class="post-metadata">

**Author:** ![qinyyuu](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/qinyyuu/32/11223_2.png) [@qinyyuu](https://forums.developer.nvidia.com/u/qinyyuu)\
**Post date:** [October 15, 2019, 5:47am UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215/6 "2019-10-15T05:47:52Z")

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reflash the jetson tx2 system？

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<div class="post-metadata">

**Author:** ![ShaneCCC](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/shaneccc/32/14043_2.png) [@ShaneCCC](https://forums.developer.nvidia.com/u/ShaneCCC)\
**Post date:** [October 15, 2019, 5:58am UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215/7 "2019-10-15T05:58:48Z")

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Yes modify the cfg file and reflash the system.

[https://elinux.org/Jetson/TX2\_SPI#Modifying\_the\_Pinmux\_Configuration](https://elinux.org/Jetson/TX2_SPI#Modifying_the_Pinmux_Configuration)

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<div class="post-metadata">

**Author:** ![qinyyuu](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/qinyyuu/32/11223_2.png) [@qinyyuu](https://forums.developer.nvidia.com/u/qinyyuu)\
**Post date:** [October 15, 2019, 6:05am UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215/8 "2019-10-15T06:05:24Z")

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Is there a way to not reflash the system?

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<div class="post-metadata">

**Author:** ![ShaneCCC](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/shaneccc/32/14043_2.png) [@ShaneCCC](https://forums.developer.nvidia.com/u/ShaneCCC)\
**Post date:** [October 15, 2019, 6:22am UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215/9 "2019-10-15T06:22:32Z")

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You can use the devmem2 to write the REG before using SPI, however you have do it after system is reset every time.

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<div class="post-metadata">

**Author:** ![qinyyuu](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/qinyyuu/32/11223_2.png) [@qinyyuu](https://forums.developer.nvidia.com/u/qinyyuu)\
**Post date:** [October 15, 2019, 7:20am UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215/10 "2019-10-15T07:20:03Z")

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thanks！

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<div class="post-metadata">

**Author:** ![nadeemm](https://sea2.discourse-cdn.com/nvidia/user_avatar/forums.developer.nvidia.com/nadeemm/32/367020_2.png) [@nadeemm](https://forums.developer.nvidia.com/u/nadeemm)\
**Post date:** [October 18, 2021, 6:34pm UTC](https://forums.developer.nvidia.com/t/jetson-tx2-spidev/83215/11 "2021-10-18T18:34:14Z")

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