It worked many times before !!

My project is an internet radio using an ESP32 (Heltec wifi kit 32 with built in 1306 display). The coding has compiled and worked many times in the past with no problems whatsoever. Recompiling that SAME code results in no display on the 1306 screen at all, total blank. Compiling gives no problems, no errors, no warnings. The radio itself works fine … just no display

The code uses the SSD1306.h library. If I upload a simple sketch using the #include <U8x8lib.h> library the display works fine. So the display is functioning.

I can include the code but it is long and there have been no changes. I should also mention that any other sketch I’ve uploaded that uses the SSD1306.h library will not print to the 1306 display. Again total blank.

Was the library itself changed and updated unknown to me? What other possible explanation ??

Thanks for any suggestions you can offer …

I’m sorry, my ouija board is broken.

You’re going to have to provide more detail

I tried to post the code but it's just too long. However below is another sketch using the same library which also compiles and loads without problems, but produces no display. If I can figure out why this sketch doesn't work, I know I can make my radio sketch work. thanks ...

#include "SSD1306.h"

SSD1306 display(0x3c, 21, 22);

int progress = 0;

void setup(){

void loop(){


progress = (progress + 10) % 110;

display.drawProgressBar(20, 20, 100, 20, progress);


Install a previous version of the library you are using. You might have to go back several versions to get the working version.

thanks Idahowalker an excellent idea, but ... no joy. I went back and tried 3 different versions with the same results with the same results - nothing on the display.

Try a simpler thing. Just a line, or some text. Is it wiring? Power? Contrast?

wildbill …took your suggestion and tried an even simpler sketch. Same thing, compiles, no errors, but no display. power & contrast fine.

#include <Wire.h>
#include “SSD1306.h”
SSD1306 display(0x3c, 4, 15);

void setup() {

display.drawString(0, 0, “Hello World”);

void loop() {}