OLED Flashing positive text to negative text

Other Hardware Displays
1

Hello

I have a 128X64 OLED from ebay current constructor (U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_NONE|U8G_I2C_OPT_DEV_0))

What I would like to do is put text up on the screen that flashes 'text pixels on' 'rest of screen pixels off' then after a short delay 'text pixels off' 'remaining screen pixels on'. In a kind of warning positive to negative flashing sequence. Any one know of a way to do that. I'm having trouble with the negative text.

Ideas or Example text is very welcome.

Thanks

2

Hi.

Please confirm that what you are looking for, is the entire display to invert, and that you have the display working right now, actually as a SSD1306.
If so, you can send a simple command to do that (inverse display on and another to switch that off).
I have that on another PC, perhaps later today i can search for that (it's too hot around here to be bothered right now, to be honest).

3

The commands for the SSD1306 are 0xA6 (normal) and 0xA7 (reverse).

I would first check to see if u8glib has a method for doing this. But if not, you could just send the bytes over I2C yourself.

4

Hello MAS3, Hope it cools down soon. Yes all is functioning normally. If you have an example great.

Hello Jboyton. Thanks I didn't see anything so far that does it through U8glib. may be wrong. I will try the hex code suggested and give feedback thanks.

5

It is not so clear to me, what you want to do, but i guess it could also be done by writing a full screen box and inverted text with u8glib.

Oliver

6

Solved jboyton: Worked thanks applied similar code to this now the screen flashes to alert that the door is open.

void DoorSw() {

u8g.firstPage();
do {

u8g.setFont(u8g_font_courB18r);
u8g.drawStr( 12, 18, "GARAGE");
u8g.drawStr( 23, 36, "DOOR");
u8g.drawStr( 8, 56, " OPEN");
Wire.beginTransmission(OLED_I2C_ADDRESS);
Wire.write(OLED_CONTROL_BYTE_CMD_STREAM);
Wire.write(0xA7);
Wire.endTransmission();
} while( u8g.nextPage() );

delay (1000);

u8g.firstPage();
do {

u8g.setFont(u8g_font_courB18r);
u8g.drawStr( 12, 18, "GARAGE");
u8g.drawStr( 23, 36, "DOOR");
u8g.drawStr( 8, 56, " OPEN");
Wire.beginTransmission(OLED_I2C_ADDRESS);
Wire.write(OLED_CONTROL_BYTE_CMD_STREAM);
Wire.write(0xA6);
Wire.endTransmission();
} while( u8g.nextPage() );
}

1 Like
7

Nice, well done.

Now you're done with the proof of concept, go find out how to do this a bit more efficient, and dump the delay (all delays).
And get used to doing things that way in the future.
Will save you lots of timing trouble.