I just finished an upscaled 5U version of uO&C for my large format rack (which is using Eurorack power, like Kosmo, but 220mm height). Let’s call it MakroO&C.
To make it better looking, and just because I recently became addicted to BIGGER interfaces, I had to put in a 2.4" OLED instead of the 0.96" OLED which comes with the original O&C and Hemisphere. After realizing that the New Haven OLED (as used in Monome Teletype) is slightly over the top for O&C (we do not need grayscale), I went for an (inexpensive) EastRising display based on the SSD1309 (1306 in the original).
As the East Rising display is slightly slower than the smaller OLEDs, I had to add DMA sub-page transfer and dynamic SPI bus frequency switching to the original driver. Even though I did general timing tests using an analyzer, I consider this a beta and would be happy if others would try it out.
Please note that the bigger display cannot be powered by the O&C PCB, it needs its own 5V (which I took from my rack bus).
2.4" for the original O&C firmware:
2.4" Hemisphere firmware:
If there are any dedicated forums where I would find more O&C users/developers, please let me know.