STM32F4 LTDC学习

很久没有写东西了，也很久没看文档了吼吼，觉得有点无聊，找来F4看看，主要看F429。督促自己多看多记录。

首先配置同步时序先看参考手册

下面看一个实际例子，一块439的开发板

设置：

  LTDC_InitStruct.LTDC_HorizontalSync = ;

   /*  */

   LTDC_InitStruct.LTDC_VerticalSync = ;

   /*  */

   LTDC_InitStruct.LTDC_AccumulatedHBP = ;

   /*  */

   LTDC_InitStruct.LTDC_AccumulatedVBP = ;

   /*  */

   LTDC_InitStruct.LTDC_AccumulatedActiveW = ;

   /*  */

   LTDC_InitStruct.LTDC_AccumulatedActiveH = ;

   /*  */

   LTDC_InitStruct.LTDC_TotalWidth = ;

   /*  */

   LTDC_InitStruct.LTDC_TotalHeigh = ;

   LTDC_Init(&LTDC_InitStruct);

配置时序

注意每个参数定义，之前是累加

看下完整的初始化代码

 void LCD_Init(void)

 {

   LTDC_InitTypeDef       LTDC_InitStruct;

   LTDC_Layer_InitTypeDef LTDC_Layer_InitStruct;

   LTDC_Layer_TypeDef     LTDC_Layerx;

   /* IO¿Ú³õÊ¼»¯ */

   LCD_GPIOInit();

   LCD_DisplayOff();

   /* Ê¹ÄÜLCDÊ±ÖÓ */

   RCC_APB2PeriphClockCmd(RCC_APB2Periph_LTDC, ENABLE);

   /* Ê¹ÄÜDMAÊ§×Ù*/

   RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2D, ENABLE);

   /* Ë®Æ½Í¬²½ÐÅºÅ---µÍµçÆ½ÓÐÐ§ */

   LTDC_InitStruct.LTDC_HSPolarity = LTDC_HSPolarity_AL;

   /* ´¹Ö±Í¬²½ÐÅºÅ---µÍµçÆ½ÓÐÐ§ */

   LTDC_InitStruct.LTDC_VSPolarity = LTDC_VSPolarity_AL;

   /* Êý¾ÝÊ¹ÄÜÐÅºÅ---µÍµçÆ½ÓÐÐ§ */

   LTDC_InitStruct.LTDC_DEPolarity = LTDC_DEPolarity_AL;

   /* ÏñËØÊ±ÖÓÅäÖÃ--- */

   LTDC_InitStruct.LTDC_PCPolarity = LTDC_DEPolarity_AL;

     /* LCD±³¹âÉèÖÃ */

   LTDC_InitStruct.LTDC_BackgroundRedValue = ;

   LTDC_InitStruct.LTDC_BackgroundGreenValue = ;

   LTDC_InitStruct.LTDC_BackgroundBlueValue = ;

   /*

    ****************************************************************************

    *PLLSAI_VCO = HSE*PLLSAI_N / PLL_M = 8 * 192 / 8 = 192MHz

    *PLLLCDCLK = PLLSAI_VCO / PLLSAI_R = 192 / 3 = 64 Mhz

    *LTDC clock frequency = PLLLCDCLK / RCC_PLLSAIDivR = 64 / 8 = 8 Mhz

    ****************************************************************************

    */

   RCC_PLLSAIConfig(, , );

   RCC_LTDCCLKDivConfig(RCC_PLLSAIDivR_Div4);

   /* Ê¹ÄÜPLLSAIÊ±ÖÓ */

   RCC_PLLSAICmd(ENABLE);

   /* µÈ´ýPLLSAIÊ±ÖÓ */

   while(RCC_GetFlagStatus(RCC_FLAG_PLLSAIRDY) == RESET){}

   /*  */

   LTDC_InitStruct.LTDC_HorizontalSync = ;

   /*  */

   LTDC_InitStruct.LTDC_VerticalSync = ;

   /*  */

   LTDC_InitStruct.LTDC_AccumulatedHBP = ;

   /*  */

   LTDC_InitStruct.LTDC_AccumulatedVBP = ;

   /*  */

   LTDC_InitStruct.LTDC_AccumulatedActiveW = ;

   /*  */

   LTDC_InitStruct.LTDC_AccumulatedActiveH = ;

   /*  */

   LTDC_InitStruct.LTDC_TotalWidth = ;

   /*  */

   LTDC_InitStruct.LTDC_TotalHeigh = ;

   LTDC_Init(&LTDC_InitStruct);

   LTDC_Layer_InitStruct.LTDC_HorizontalStart = ;

   LTDC_Layer_InitStruct.LTDC_HorizontalStop = ( +  - );

   LTDC_Layer_InitStruct.LTDC_VarticalStart = ;

   LTDC_Layer_InitStruct.LTDC_VerticalStop = ( +  - );    

   /* Pixel Format configuration*/

   LTDC_Layer_InitStruct.LTDC_PixelFormat = LTDC_Pixelformat_RGB565;

   /* Alpha constant (255 totally opaque) */

   LTDC_Layer_InitStruct.LTDC_ConstantAlpha = ;

   /* Default Color configuration (configure A,R,G,B component values) */

   LTDC_Layer_InitStruct.LTDC_DefaultColorBlue = ;

   LTDC_Layer_InitStruct.LTDC_DefaultColorGreen = ;

   LTDC_Layer_InitStruct.LTDC_DefaultColorRed = ;

   LTDC_Layer_InitStruct.LTDC_DefaultColorAlpha = ;

   /* Configure blending factors */

   LTDC_Layer_InitStruct.LTDC_BlendingFactor_1 = LTDC_BlendingFactor1_CA;

   LTDC_Layer_InitStruct.LTDC_BlendingFactor_2 = LTDC_BlendingFactor2_CA;

   /* the length of one line of pixels in bytes + 3 then :

      Line Lenth = Active high width x number of bytes per pixel + 3

      Active high width         = LCD_PIXEL_WIDTH

      number of bytes per pixel = 2    (pixel_format : RGB565)

   */

   LTDC_Layer_InitStruct.LTDC_CFBLineLength = (( * ) + );

   /*  the pitch is the increment from the start of one line of pixels to the

       start of the next line in bytes, then :

       Pitch = Active high width x number of bytes per pixel

   */

   LTDC_Layer_InitStruct.LTDC_CFBPitch = ( * );

   /* configure the number of lines */

   LTDC_Layer_InitStruct.LTDC_CFBLineNumber = ;

   /* Input Address configuration */

   LTDC_Layer_InitStruct.LTDC_CFBStartAdress = LCD_FRAME_BUFFER;

   LTDC_LayerInit(LTDC_Layer1, &LTDC_Layer_InitStruct);

   /* Configure Layer2 */

   LTDC_Layer_InitStruct.LTDC_CFBStartAdress = LCD_FRAME_BUFFER + BUFFER_OFFSET;

   LTDC_Layer_InitStruct.LTDC_BlendingFactor_1 = LTDC_BlendingFactor1_PAxCA;

   LTDC_Layer_InitStruct.LTDC_BlendingFactor_2 = LTDC_BlendingFactor2_PAxCA;

   LTDC_LayerInit(LTDC_Layer2, &LTDC_Layer_InitStruct);

   LTDC_ReloadConfig(LTDC_IMReload);

   /* Enable foreground & background Layers */

   LTDC_LayerCmd(LTDC_Layer1, ENABLE);

 //  LTDC_LayerCmd(LTDC_Layer2, ENABLE);

   LTDC_ReloadConfig(LTDC_IMReload);

   LCD_DisplayOn();

 }

LCD_Init

LTDC_DefaultColorBlue就是背景色

每个Layer支持窗口（Window）操作，所谓Window，就是指该层的图像只有在Window区域内有效，而Window区域外则用该层的DefaultColor填充。如下图：

填色直接写内存

 int main (void)

 {

   uint32_t i, j;

   uint16_t *addr = (uint16_t *)LCD_FRAME_BUFFER;

   SDRAM_Init();

   LCD_Init();

     j = ;

   while () {

     for (i = ; i < 0x2000000;i++);

     for (i = ; i <  * ; i++)

     {

       addr[i] =  << j;

     }

     j++;

     if (j > )j = ;

   }

 }

LCD display RGB

巴特西

STM32F4 LTDC学习

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