SSD1306 text not working

[Angus Schmaloer]

Hey,

I want to use the SSD1306 display with the STM32F103 controller.
In the "gfxInit();" the uGFX logo is shown, which implies that the I2C works (the write_cmd  and write_data).
But when i want to display some text, notting happens.
I write:
"  font1 = gdispOpenFont("DejaVuSans12");
  font2 = gdispOpenFont("DejaVuSans20");

  // Show some stuff on the display
  gdispDrawString(5, 5, "Hello uGFX!", font2, Black);
  gdispDrawString(5, 35, "Temp. 1: 24.1", font1, Black);
  gdispDrawString(5, 50, "Temp. 2: 28.3", font1, Black);"

But the write_cmd  and write_data are never called (except in the init funct) and the controller is never sending data.

[Joel Bodenmann]

The SSD1306 is a flush-based GDISP driver. The driver maintains a framebuffer itself which needs to be copied to the actual display controller's framebuffer. That operation is called flushing. Try to call gdispFlush() after rendering. You will find configuration options for flushing in the configuration file and more information in this forum.

[Angus Schmaloer]

aaah okey, i will look into that.

35 minutes ago, Joel Bodenmann said:

The SSD1306 is a flush-based GDISP driver.

But i couldn't find anything about flushing in the "stm32f401re_nuleo_ssd1306" example project.


UPDATE
It is working now, thanks, saved me a lot a looking around and searching

Edited July 18, 2018 by Angus Schmaloer

[Joel Bodenmann]

1 hour ago, Angus Schmaloer said:

But i couldn't find anything about flushing in the "stm32f401re_nuleo_ssd1306" example project.

That project will most likely use auto-flushing or timer based flushing which is simply a setting in gfxconf.h.