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zaher

Display is intermittent - SSD1322

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I just realized that everything is being displayed like this on my LCD. This is the result of calling: 

gdispClear(White);
gdispFlush();

These are the defines I have enabled in the _GDISP_LLD_CONFIG_H file:

#define GDISP_HARDWARE_FLUSH			TRUE		// This controller requires flushing
#define GDISP_HARDWARE_DRAWPIXEL		TRUE
#define GDISP_HARDWARE_PIXELREAD		TRUE
#define GDISP_HARDWARE_CONTROL      	TRUE

#define GDISP_LLD_PIXELFORMAT			GDISP_PIXELFORMAT_GRAY16

And here is what I have enabled in gfxconf.h:

#define GFX_USE_OS_FREERTOS                            TRUE
#define GFX_OS_NO_INIT                           TRUE
///////////////////////////////////////////////////////////////////////////
// GDISP                                                                 //
///////////////////////////////////////////////////////////////////////////
#define GFX_USE_GDISP                                  TRUE

#define GDISP_NEED_AUTOFLUSH                           FALSE
//#define GDISP_NEED_TIMERFLUSH                        FALSE
#define GDISP_NEED_VALIDATION                          TRUE
#define GDISP_NEED_CLIP                                TRUE
#define GDISP_NEED_CIRCLE                              TRUE
#define GDISP_NEED_DUALCIRCLE                          TRUE
#define GDISP_NEED_ELLIPSE                             TRUE
#define GDISP_NEED_ARC                                 TRUE
#define GDISP_NEED_ARCSECTORS                          TRUE
#define GDISP_NEED_CONVEX_POLYGON                      TRUE
#define GDISP_NEED_SCROLL                              TRUE
#define GDISP_NEED_PIXELREAD                           TRUE
#define GDISP_NEED_CONTROL                             TRUE
#define GDISP_NEED_TEXT                                TRUE
#define GDISP_NEED_ANTIALIAS                           TRUE
#define GDISP_NEED_UTF8                                TRUE
#define GDISP_INCLUDE_FONT_UI1                         TRUE
#define GDISP_INCLUDE_FONT_UI2                   	   TRUE		// The smallest preferred font.
#define GDISP_INCLUDE_FONT_UI1                         TRUE
#define GDISP_INCLUDE_FONT_UI2                   	   TRUE		// The smallest preferred font.
#define GDISP_NEED_STARTUP_LOGO                        TRUE
#define GDISP_TOTAL_DISPLAYS                             1

Any ideas? 

Intermittent Display.jpg

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It looks like the column order on your display might be a bit different to the standard arrangement.

Check the initialisation sequence particularly around the column order settings.

The other place to look is around the spi data format eg if you are outputting 9 bit spi bit the controller expects 8 bit spi (or visa versa) you will get similar symptoms.

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Here is my SPI init code:

static void MX_SPI2_Init(void)
{

  hspi2.Instance = SPI2;
  hspi2.Init.Mode = SPI_MODE_MASTER;
  hspi2.Init.Direction = SPI_DIRECTION_1LINE;
  hspi2.Init.DataSize = SPI_DATASIZE_8BIT;
  hspi2.Init.CLKPolarity = SPI_POLARITY_LOW;
  hspi2.Init.CLKPhase = SPI_PHASE_1EDGE;
  hspi2.Init.NSS = SPI_NSS_SOFT;
  hspi2.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_2;
  hspi2.Init.FirstBit = SPI_FIRSTBIT_MSB;
  hspi2.Init.TIMode = SPI_TIMODE_DISABLE;
  hspi2.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
  hspi2.Init.CRCPolynomial = 7;
  if (HAL_SPI_Init(&hspi2) != HAL_OK)
  {
    Error_Handler();
  }

}

I tried with many different prescalers (4, 16, 32), datasize, clock polarity, nothing worked. And by the way, since the drawing functions from an existing SSD1322 driver work out of the box on the current SPI setup, I doubt the interface has anything to do with it. 

And this is the init sequence for the SSD1322:

LLDSPEC bool_t gdisp_lld_init(GDisplay *g) {
	// The private area is the display surface.
	g->priv = gfxAlloc(GDISP_SCREEN_HEIGHT * SSD1322_ROW_WIDTH);

	// Initialise the board interface
	init_board(g);
	post_init_board(g);

	// Hardware reset
	HAL_GPIO_WritePin(LCD_RESET_GPIO_Port, LCD_RESET_Pin, SET);
	HAL_Delay(50);
	HAL_GPIO_WritePin(LCD_RESET_GPIO_Port, LCD_RESET_Pin, RESET);
	HAL_Delay(100);
	HAL_GPIO_WritePin(LCD_RESET_GPIO_Port, LCD_RESET_Pin, SET);
	HAL_Delay(40);

	write_cmd(g,CMD_SET_COMMAND_LOCK);
	write_data(g,0x12); // Unlock OLED driver IC

	write_cmd(g,CMD_SET_DISPLAY_OFF);

	write_cmd(g,CMD_SET_CLOCK_DIVIDER);
	write_data(g,0x91);

    write_cmd(g,CMD_SET_MULTIPLEX_RATIO);
    write_data(g,0x3F); //duty = 1/64*,64 COMS are enabled

    write_cmd(g,CMD_SET_DISPLAY_OFFSET);
    write_data(g,0x00);

    write_cmd(g,CMD_SET_DISPLAY_START_LINE); //set start line position
    write_data(g,0x00);

    write_cmd(g,CMD_SET_REMAP);
    write_data(g,0x14);	//Horizontal address increment,Disable Column Address Re-map,Enable Nibble Re-map,Scan from COM[N-1] to COM0,Disable COM Split Odd Even
    write_data(g,0x11);	//Enable Dual COM mode

    write_cmd(g,0xB5); //GPIO
    write_data(g,0x00);
    //writeCommand(0x00);

    write_cmd(g,CMD_SET_FUNCTION_SELECTION);
    write_data(g,0x01);//  selection external VDD

    write_cmd(g,CMD_DISPLAY_ENHANCEMENT);
    write_data(g,0xA0);//	enables the external VSL
    write_data(g,0xb5);//	0xfd,Enhanced low GS display quality;default is 0xb5(normal),

    write_cmd(g,CMD_SET_CONTRAST_CURRENT);
    write_data(g,0x7f); // 0xff 	default is 0x7f

    write_cmd(g,CMD_MASTER_CURRENT_CONTROL);
    write_data(g,0x0f);	//default is 0x0f

    write_cmd(g,0xB9); //GRAY TABLE,linear Gray Scale

    write_cmd(g,CMD_SET_PHASE_LENGTH);
    write_data(g,0xE2);	// default is 0x74

    write_cmd(g,CMD_DISPLAY_ENHANCEMENT_B);
    write_data(g,0xA2);	// Reserved;default is 0xa2(normal)
    write_data(g,0x20);

    write_cmd(g,CMD_SET_PRECHARGE_VOLTAGE);
    write_data(g,0x1F);	// 0.6xVcc

    write_cmd(g,CMD_SET_SECOND_PRECHARGE_PERIOD);
    write_data(g,0x08);	// default

    write_cmd(g,CMD_SET_VCOMH_VOLTAGE	);
    write_data(g,0x07);	// 0.86xVcc;default is 0x04

    write_cmd(g,CMD_SET_DISPLAY_MODE_NORMAL);

    write_cmd(g,CMD_EXIT_PARTIAL_DISPLAY);

    write_cmd(g,CMD_SET_DISPLAY_ON);
    // Finish Init
    post_init_board(g);



	/* Initialise the GDISP structure */
	g->g.Width = GDISP_SCREEN_WIDTH;
	g->g.Height = GDISP_SCREEN_HEIGHT;
	g->g.Orientation = GDISP_ROTATE_0;
	g->g.Powermode = powerOn;
	g->g.Backlight = GDISP_INITIAL_BACKLIGHT;
	g->g.Contrast = GDISP_INITIAL_CONTRAST;
	return TRUE;
}

 

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