How to write simple text or display image on the SSD1322 OLED display
It's always a bit of a headache to interface a display until you get it working as you usually have little ways to know what is wrong, it can be the protocol, the bus, wrong init, wrong data format, wrong bus settings, or any other hardware issue.
The best is to use a logic bus analyzer to check if what your MCU is sending matches the datasheet.
There are no &quot;good magic&quot; ways to debug besides reading the datasheet again and again and checking for sample codes and check the circuit if you are missing pullups and such sort of things.
A good way is to have some working demo board using the same display so you can compare what is sent to the bus and it gives you a reference and a starting point.
Also, make sure your display actually works, sometimes it's good to have a couple of them.