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I have been working on installing rf controls through my Rpi4 and Sean's hat recently to provide autopilot controls at the helm station instead of just in the cabin navigation station. The RPI works fine with OpenPlotter, Pypilot, and the autopilot, but I have been unable to get the RF transmitters to communicate with the hat. The blue LED flashes on a command from the transmitter and the backlight works on the hat, but there is no other data on the LCD screen and no transfer of data from the transmitter to the autopilot.
Any ideas of what needs to be fixed would be helpful.
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Yes, it is most likely you must enable and start the pypilot_hat service which is separate from pypilot itself. This service renders to the LCD display as well as reads and relays the remote controls.
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its normally in debian systems, check if it is running
systemctl status pypilot_hat
then to enable and start
systemctl enable pypilot_hat
systemctl start pypilot_hat
you need to enable pi in the raspbi-config if it is not enabled it won't work.
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Sean, thank you for the quick reply.
I have performed the four commands listed above to no avail.
How would I enable pi in the rasbi-config?
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did you run the raspbi-config command and enable spi then reboot?
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Sean, thanks for the response.
SSH, VNC, SPI, I2V and Serial Port are all enabled in Rasp Config
sysemctl status pypilot_hat Loaded:loaded Active: active (running)
After reboot:
pi@pi:~ $ systemctl status pypilot_hat
* pypilot_hat.service - pypilot hat
Loaded: loaded (/etc/systemd/system/pypilot_hat.service; enabled; preset: >
Active: active (running) since Sat 2025-11-08 22:45:12 EST; 6min ago
Main PID: 662 (pypilot_hat)
Tasks: 1 (limit: 1573)
CPU: 396ms
CGroup: /system.slice/pypilot_hat.service
`-662 /usr/bin/python3 /usr/local/bin/pypilot_hat
Nov 08 22:49:59 pi pypilot_hat[662]: retrying to setup gpio with edge detect.
Nov 08 22:49:59 pi pypilot_hat[662]: WARNING Failed to add edge detection on pi>
Nov 08 22:49:59 pi pypilot_hat[662]: retrying to setup gpio with edge detect.
Nov 08 22:49:59 pi pypilot_hat[662]: WARNING Failed to add edge detection on pi>
Nov 08 22:49:59 pi pypilot_hat[662]: retrying to setup gpio with edge detect.
Nov 08 22:49:59 pi pypilot_hat[662]: WARNING Failed to add edge detection on pi>
Nov 08 22:49:59 pi pypilot_hat[662]: retrying to setup gpio with edge detect.
Nov 08 22:49:59 pi pypilot_hat[662]: WARNING Failed to add edge detection on pi>
Nov 08 22:49:59 pi pypilot_hat[662]: retrying to setup gpio with edge detect.
Nov 08 22:49:59 pi pypilot_hat[662]: WARNING Failed to add edge detection on pi>
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does anything display on the screen?
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Sean,
Nothing displays on the screen. The screen is backlit. This is the case on both my R Pi4 and R Pi 5
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what happens if you stop pypilot hat:
sudo systemctl stop pypilot_hat
then run it from the console:
sudo pypilot_hat
and post the output? I am wondering if it is using the wrong lcd driver. Otherwise it could be defective lcd.. Can you connect to localhost:33333 in a browser?
