I have a Raspberry Pi with a Sense Hat that has never had an HDMI cable plugged into it. I have written small programs with the Python module that operate the

I have a Raspberry Pi with a Sense Hat that has never had an HDMI cable plugged into it. I have written small programs with the Python module that operate the LED matrix that work fine AFAICT. The LED matrix also happens to be a framebuffer device, and it is possible that your error was about the LED matrix. The LED matrix is an RGB565 framebuffer with the id "RPi-Sense FB". The appropriate device node can be written to as a standard file or mmap-ed. https://www.raspberrypi.org/documentation/hardware/sense-hat/ https://www.raspberrypi.org/documentation/hardware/sense-hat...