First we need to check your connections. Which Arduino board are you using and what connections have you made between the Arduino board and the display? I need a simple net list, I. E. Connected Arduino pin 13 to display pin x, etc etc
How are you powering the display?
Also attach the sketch for checking, since you may not be using the correct one.
Also please confirm you have set the configuration links on the display board for 4 wire SPI as per pdf document. This may involve fitting or removing links or resistors.
I see that R18 and R21 are fitted, this means the display is configured for the parallel interface (8080 MCU mode) in the diagram you provided a link to.
If you want to use the 4 wire SPI interface you will need to unsolder the link resistor from position R18 and refit it in position R19. Then try your sketch again.
Based on the discussion in the thread you mention, and after examining the "Hello world" example sketch, the constructor line you should use for the SPI 4 line interface is:
If you have changed the pin allocations in that constructor to the ones you have wired up then it may work, but the SPI data and clock lines will then be "bit bashed" by software hence display updates will be relatively slow. It would be advisable to use the hardware SPI pins as listed in the constructor above.
Looking at the data sheet indicates the display has 3.3V input logic levels, the 5V levels from the UNO may damage it, thus you should add protection resistors in line with some connections. I have no way of testing this but I would try the connections as follows:
be:
OLED ARDUINO UNO
1 GND
2 5V
3 ------
4 through 1K2 resistor to pin 13 (SCLK)
5 through 1K2 resistor to pin 11 (SDIN)
6 ------
7 ------
8 ------
9 ------
10 ------
11 ------
12 ------ (or connect to 3.3V, or via 10K resistor to 5V)
13 ------ (or connect to 3.3V, or via 10K resistor to 5V)
14 through 1K2 resistor to pin 9 (/DC)
15 through 1K2 resistor to RESET
16 through 1K2 resistor to pin 10 (/CS)
The 1K2 resistors should protect the display logic inputs from damage.