Getting the 1351 OLEDs to work is quite a pain. Hopefully, in the future, it can be included in Teensyunio.

If you try and load it from here: https://www.arduinolibraries.info/li...sd1351-library and use the test example, it then requires manually installing the GFX library. The GFX library then requires the I2CDevice Library which doesn't seem to exist. For others than go down this rabbit hole, you need the BUSio library: https://www.arduinolibraries.info/li...dafruit-bus-io

I am aware of the really outdated example program teensy_ssd1351, but that has very limited support and does not use the newer adafruit-ssd1351 (a different library). It's confusing there are all these varients that all work differently.