I just added guide to our Raspberry Pi guide collection for Xojo.
The new guide is about how to control SSD1306 displays with I2c interface from Xojo.
SSD1306 displays are pixel based raster displays so to be able to send text to it then we had to create font rendering system also which the Xojo project in the guide handles.
(This last one had to small screen to display the whole message that was fed to it)
Our guide collection can be found here:
The guides use free and open source GPIO Plugin for Xojo , I2C Plugin for Xojo and SPI Plugin for Xojo. (Additionally then the new guide uses free TypeLib Plugin).