The TX2(JetPack 3.0) can't access FAN

Robotics & Edge Computing Jetson Systems Jetson TX2
1

I got a problem with FAN on my custom base board. But it works fine on the developed board.
It is nothing on the pwm output pin.The error is shown below:

nvidia@tegra-ubuntu:~$ sudo ./jetson_clocks.sh
[sudo] password for nvidia:
Can't access Fan!

Thanks!

2

Hi Hongsheng,

What’s the different of your custom carrier board compared with origin carrier board? Maybe that’s caused by device tree issue, bot really sure, but you can refer to [url]https://elinux.org/Jetson/TX2_DTB[/url].

Besides, could you try JetPack3.1/R28.1 to confirm again?

Thanks

3

There is nothing between the two circuit of FAN but the ‘enable’ signal,see to attachment for custom carrier board.

I can’t use the JetPack3.1/R28.1 due to some reasons.

Does any other circuit needed for FAN ? It works well on the origin carrier board.

Thanks

20171108143354.jpg
20171108143354.jpg3725×1484 3.7 MB

20171108143354.jpg
20171108143354.jpg3725×1484 3.7 MB

4

Hi, please measure the signal first.

  1. If the 1.8V, 5V are normal
  2. If the ‘FAN_TACH’ will be driven to low when fan attached.
  3. If the ‘FAN_PWM’ output waveform is normal when set it output PWM signal, and what’s the waveform on pin 4 at this time.
5
  1. The 1.8V,5V are both normal
  2. The ‘FAN_TACH’ will be driven to low when fan attached.
  3. The ‘FAN_PWM’ output is drived high on the custom carrier board all the time,and nothing on pin 4.

The ‘FAN_PWM’ output waveform is normal with or without FAN, and ‘FAN_TACH’ is normal with FAN on the origin carrier board.

Thandks!

6

Hi

Have you clarified the cause and resolved the problem?
Any result can be shared?

Thanks

7

I had a SD card installed when installing Jetpack, some how the Jeston was failing to read from the debug file system. Re-flashing the Jetson without the SD allowed the fan to start. Hope this helps, I couldn’t find a good answer but I had this with Two Jetsons and this seem to fix them.