Problem with oled display and hardware SPI

olikraus:
If it is something different, then maybe the HW SPI pins are at different positions.

While there are all sorts of variations available as "clones", many of which are mendaciously described as UNOs when lacking the 32U4 auxiliary chip they are actually clones of the earlier Duemilanove and not UNOs at all, it is pretty unlikely they would have the SPI pins in different places. :astonished: