Rotate 180 degrees a SSD1306 oled on RPI

[jancotipsarevic]

Hello, I am starting using this amazing library, I am not an expert in cpp but a need to use it. This simple example works as expected but the board I am using has the oled physically rotated 180 degrees, so I need to rotate it but I dont know how to do it. I believe it is a matter of cpp knowledge. I need to overcome this issue to follow with my tests. I'd really appreciate your help.

Thank you very much.

int main(int argc, char **argv) { DisplaySSD1306_128x64_I2C display((int8_t) 5, { -1, 0x3D, -1, -1, 0 }); display.begin(); display.clear(); display.drawLine(10,10,50,10); display.setFixedFont(ssd1306xled_font6x8); display.printFixed (0, 8, "Line 1. Normal text", STYLE_NORMAL); cout << "Finished!, press any key to continue" << endl; cin.get(); return EXIT_SUCCESS; }

[jancotipsarevic]

I've managed to solved it by changing the init funtion and compile a new lib. This function is located at /lcdgfx/src/v2/lcd/ssd1306/lcd_ssd1306.inl.

/*//ORIGINAL FUNCTION static const PROGMEM uint8_t s_SSD1306_lcd128x64_initData[] = {

ifdef SDL_EMULATION

SDL_LCD_SSD1306, 0x00,
0x00, 0x00,

endif

0xAE, 0x00,          // display off
0x20, 0x01, 0x00,    // Page horizontal Addressing mode
0xC8, 0x00,          // Scan from 127 to 0 (Reverse scan)
0x40| 0x00, 0x00,    // First line to start scanning from
0x81, 0x01, 0x7F,    // contast value to 0x7F according to datasheet
0xA0| 0x01, 0x00,    // Use reverse mapping. 0x00 - is normal mapping
0xA6, 0x00,          // Normal display
0xA8, 0x01, 63,      // Reset to default MUX. See datasheet
0xD3, 0x01, 0x00,    // no offset
0xD5, 0x01, 0x80,    // set to default ratio/osc frequency
0xD9, 0x01, 0x22,    // switch precharge to 0x22 // 0xF1
0xDA, 0x01, 0x12,    // set divide ratio
0xDB, 0x01, 0x20,    // vcom deselect to 0x20 // 0x40
0x8D, 0x01, 0x14,    // Enable charge pump
0xA4, 0x00,          // Display resume
0xAF, 0x00,          // Display on

}; */ //ROTATED 180 DEGREES static const PROGMEM uint8_t s_SSD1306_lcd128x64_initData[] = {

ifdef SDL_EMULATION

SDL_LCD_SSD1306, 0x00,
0x00, 0x00,

endif

0xAE, 0x00,          // display off
0x20, 0x01, 0x00,    // Page horizontal Addressing mode
0xC0, 0x00,          // Scan from 127 to 0 (Reverse scan)
0x40| 0x00, 0x00,    // First line to start scanning from
0x81, 0x01, 0x7F,    // contast value to 0x7F according to datasheet
0xA0| 0x00, 0x00,    // Use reverse mapping. 0x00 - is normal mapping
0xA6, 0x00,          // Normal display
0xA8, 0x01, 63,      // Reset to default MUX. See datasheet
0xD3, 0x01, 0x00,    // no offset
0xD5, 0x01, 0x80,    // set to default ratio/osc frequency
0xD9, 0x01, 0x22,    // switch precharge to 0x22 // 0xF1
0xDA, 0x01, 0x12,    // set divide ratio
0xDB, 0x01, 0x20,    // vcom deselect to 0x20 // 0x40
0x8D, 0x01, 0x14,    // Enable charge pump
0xA4, 0x00,          // Display resume
0xAF, 0x00,          // Display on

};

[lexus2k]

Hi,

You don't need to change initialization code. You have to use display.getInterface().flipHorizontal() and display.getInterface().flipVertical() methods.

[jancotipsarevic]

Hello, well what you mention was one of my first tries but it looks like none of this methods appears under display, This is the error:

main.cpp:45:28: error: ‘class InterfaceSSD1306’ has no member named ‘flipHorizonal’; did you mean ‘flipHorizontal’? display.getInterface().flipHorizonal(); ^~~~~ flipHorizontal Process terminated with status 1 (0 minute(s), 1 second(s)) 1 error(s), 0 warning(s) (0 minute(s), 1 second(s))

And this is my code:

include

include

include

include

include "lcdgfx.h"

using namespace std;

int main(int argc, char **argv) {

DisplaySSD1306_128x64_I2C display((int8_t) 5, { -1, 0x3D, -1, -1, 0 });
display.getInterface().flipHorizonal();
display.begin();
display.clear();
display.drawLine(10,10,50,10);
display.setFixedFont(ssd1306xled_font6x8);
display.printFixed (0,  8, "Line 1. Normal text", STYLE_NORMAL);

 cout << "Finished!, press any key to continue" << endl;
 cin.get();

 return EXIT_SUCCESS;

}

[Chrispren]

I think you've misspelled "flipHorizontal" You have "flipHorizonal"

[jancotipsarevic]

Sorry, in this second try I've mispelled, now corrected but the issue persists as I saw previously. Here again the error and the code. //Error /home/pi/projects/gpiod_examples/oled_use_lib/main.cpp|45|error: no matching function for call to ‘InterfaceSSD1306::flipHorizontal()’|

//Code

include

include

include

include

include "lcdgfx.h"

using namespace std;

int main(int argc, char **argv) {

DisplaySSD1306_128x64_I2C display((int8_t) 5, { -1, 0x3D, -1, -1, 0 });
display.getInterface().flipHorizontal();
display.begin();
display.clear();
display.drawLine(10,10,50,10);
display.setFixedFont(ssd1306xled_font6x8);
display.printFixed (0,  8, "Line 1. Normal text", STYLE_NORMAL);

cout << "Finished!, press any key to continue" << endl;
cin.get();

return EXIT_SUCCESS;

}

[Chrispren]

Try this?

include "lcdgfx.h"

int main(int argc, char **argv) { DisplaySSD1306_128x64_I2C display((int8_t) 5, { -1, 0x3D, -1, -1, 0 }); display.begin(); display.clear(); display.getInterface().flipHorizontal(1); display.drawLine(10,10,50,10); display.setFixedFont(ssd1306xled_font6x8); display.printFixed (0, 8, "Line 1. Normal text", STYLE_NORMAL);

// cout << "Finished!, press any key to continue" << endl; // cin.get();

return EXIT_SUCCESS; }

[jancotipsarevic]

EXCELLENT!! now works, now rotated 180 degrees!. Congratulations this is a great library!!!!

Thank you very much.

The code now is:

int main(int argc, char **argv) {

DisplaySSD1306_128x64_I2C display((int8_t) 5, { -1, 0x3D, -1, -1, 0 });
display.begin();
display.clear();
display.getInterface().flipHorizontal(1);
display.getInterface().flipVertical(1);
display.drawLine(10,10,50,10);
display.setFixedFont(ssd1306xled_font6x8);
display.printFixed (0,  8, "Line 1. Normal text", STYLE_NORMAL);

//cout << "Finished!, press any key to continue" << endl;
//cin.get();

return EXIT_SUCCESS;

}

[Chrispren]

Glad you got it running :-)

[lexus2k]

@jancotipsarevic I', sorry for misspell. The comment is fixed. @Chrispren Thank you for clarifications