I have a board which uses a Bela Mini to communicate with an LCD display over SPI. Until now, I have been using Bela image v0.3.8b, with the Bela firmware updated to the state of the "master" branch as of last summer (4 August 2021) for the SPI library. The code is set to run on startup, and the display initialises correctly.
However, I have now tried updating to the new Bela image v0.3.8g and have encountered a strange problem. The code runs fine when launched via the Bela IDE (display initialises correctly), but when the code is launched via the startup script, the display does not initialise, and gives the following error message:
SPI: SPI_IOC_MESSAGE Failed |: Bad file descriptor
(All the other aspects of the program e.g. sensor input and audio output seem to be working fine - it is just the display that does not work.)
I have stepped back through the available Bela images, and this problem is still present using v0.3.8e (which is the next version of the image that I could fine after v0.3.8b).
I also tried to update the Bela firmware to the current state of the bela-master branch using image v0.3.8b, but this did not work (after performing the update and ssh-ing to the Bela, there is no Bela directory, only _BelaUpdateBackup).
I will be making more of these boards with the latest Bela Mini hardware (Rev C) which requires image v0.3.8g, so any suggestions for how to continue debugging would be greatly appreciated!