How could I test a I2C OLED SSD1306 display?

[bastler11]

Hello, I tried to connect a SSD1306 display to a ESP8266. I found the display after scanning the bus. The display is new but it shows nothing. Do I make any mistake? I connected the display 5V -> Vin ESP, GND -> GND ESP, SCL -> D1, SDA -> D2. Here are also two screenshots from ESPEasy.

Does anybody has an idea what I could to? How could I test des Display?

Thanks and best regards!

Ingo

[Ath]

Not sure if connecting it to 5V is the best plan, it should work just fine with 3.3V, but if the board indicates it can work with 5V, then it could be OK.

Did you set the correct type (SSD1306/SH1106) and resolution for the display? As that does make some difference for the initialization, AFAICS (don't have one close at hand to test, atm).

Edit:
Because of the nature of the display, it should not be set to Slow I2C speed, updates will then be quite slow.

[TD-er]

I'm not sure the SSD1306 will work at 5V.
I always use them at 3V3 and I don't think there are voltage regulators on board of those displays.

[bastler11]

Very good idea! It works with 3,3V

Thanks