Hidraw0 RPi3 vs RPi4

General
1

Hi there,

This is my first post. I am quite new on Node-Red, Linux & Raspberry Pi and I need your support.

I have an application running with a RPi3. I am building a new project with RPi4 and I want to reuse quite a few things and almost everyting is working just fine, except a device that I have it connected to one of the USB ports.

In the RPi3 I have an "Edit exec node" with:

sudo chmod 666 /dev/hidraw0

this is to stablish the initial connection. Then I also have several "Edit exec nodes" with the same command (just changing some sintax for different control messages) like:

sudo echo -e '\x00\x00\x00\x00\x00\x13\x00\x00\x00' > /dev/hidraw0

Like I said, the above works fine on the RPi3 but not on the RPi4.
I have tried similar approach with different values for hidraw* and dev/ttyUSB* after checking with lsusb that indeed the usb device is seen by the RPi4.

I hope some of you might have some suggestions that would help me to solve this issue.

THANKS in advance.

2

Look at udev rules to

  1. Identify the correct device
  2. Assign a fixed symbolic name to the now identified device

Search the site, there will be examples using serial ports you can use as a starting point

3

Thanks for your suggestions.
I will look into it next week again and I hope I will manage to get it working this time.

Thanks again.

4

You really pointed me in the right direction. I have now solved the issue. Big thanks.

5

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.