Ubiquity image with Sense HAT does not work

I’m trying to follow the Getting Started steps to test the Sense HAT on my Raspberry Pi 3B+.
I’m using the Ubiquity Robotics image.
When I start the simple python script, I get an error because it is impossible to find the LED matrix.
The Rpi communicate towards I2C with and Attiny that control the matrix.
The communication is working because I can detect the other modules and sensors of the board.
It seems there is a conflict with the overlay features of the image. Actually, if I comment the dtoverlay=ubiquity_led_buttons in the /boot/config.txt file, the script can run without errors.
In this way, the Rpi wifi does not work.
What should I modify to have both the functionalities?


Hi @francesca,

Could you link to the script that is failing?

Also in what way is the wifi not working when you disable the overlay? It should still work… unless there is a bug somewhere.


Here is the script
Is the very first step to test the module

from sense_hat import SenseHat
sense = SenseHat()
sense.show_message(“Hello world”)

Yes, this is also my question, because I need both: the module and also the wifi access.

What do you mean by the wifi not working? Is AP mode not working? Does wlan0 show up when you run ifconfig?

Yes, the AP mode is not working if I comment the overlay in /boot/config.txt

This is the result with the overlay commented:

Ok, one more debugging step. Can you run sudo systemctl status pifi and provide the output?

Here is the output:

Thanks for the support!


Congratulations! You found a bug in pifi. I opened a github ticket here https://github.com/rohbotics/pifi/issues/16

For a workaround, please edit /etc/pifi/pifi.conf, and comment out the lines with status_led and button_device_name. This should solve with AP mode not starting.


Ignore all that. I got it to work too. For some reason I also need to set the Monitor settings in raspi-config.

So changes were:

  1. 7 Advanced Options
  2. A5 Resolution
  3. DMT Mode 4 640x480 60Hz 4:3

Hi Francesca, did you end up getting this working?

I tried commenting out dtoverlay=ubiquity_led_buttons in the config.txt file, but then I can’t connect to the Raspberry Pi, and get the following error when I tried to connect via ssh:

ssh ubuntu@test.local
ssh: Could not resolve hostname test.local: Name or service not known

This persisted even when I commented out status_led and button_device_name from the /etc/pifi/pifi.conf. I also tried setting them both to None but that didn’t allow me to connect either?

If I unplug the Sense Hat with those settings changed it connects again via SSH?

If I don’t comment out dtoverlay=ubiquity_led_buttons and have the Sense Hat attached, it connects fine, but I can’t run any programs and get the following error:

raise OSError('Cannot detect %s device' % self.SENSE_HAT_FB_NAME)
OSError: Cannot detect RPi-Sense FB device

From a basic program like:
from sense_hat import SenseHat
sense = SenseHat()
sense.show_message(“Hello world”)

The RTIMULibDrive11 program works though and outputs readings from the Sense Hat for the roll, pitch, yaw, and temperature fine.

Adding dtoverlay=rpi-sense to the config.txt file didn’t fix it either?

Going to try on another raspberry pi image, to check the Sense Hat works now.

1 Like

@mackhina Glad you got it working. Good luck on your project.

The SSH issue is seperate, sometimes the images refuses to SSH for a while after booting up, we are working on a fix for the next image.