水平同步和时钟配置问题

beyondabcd

我是用429驱动AT070TN92-800x480 液晶屏

  /* Polarity configuration */
  /* Initialize the horizontal synchronization polarity as active low */
  hltdc_F.Init.HSPolarity = LTDC_HSPOLARITY_AL;
  /* Initialize the vertical synchronization polarity as active low */
  hltdc_F.Init.VSPolarity = LTDC_VSPOLARITY_AL;
  /* Initialize the data enable polarity as active low */
  hltdc_F.Init.DEPolarity = LTDC_DEPOLARITY_AL;
  /* Initialize the pixel clock polarity as input pixel clock */  
  hltdc_F.Init.PCPolarity = LTDC_PCPOLARITY_IPC;

1. 通过 上面的图片如何体现出这几个参数全是低电平有效？
2.像素时钟 怎么有的版本是LTDC_PCPOLARITY_IPC参数，有的是LTDC_PCPolarity_IPC 如何通过芯片手册查找这个参数？

beyondabcd

/* Layer1 Configuration ------------------------------------------------------*/
   /* Windowing configuration */
  /* In this case all the active display area is used to display a picture then :
     Horizontal start = horizontal synchronization + Horizontal back porch = 43
     Vertical start   = vertical synchronization + vertical back porch     = 12
     Horizontal stop = Horizontal start + window width -1 = 43 + 480 -1
     Vertical stop   = Vertical start + window height -1  = 12 + 272 -1      */
  pLayerCfg.WindowX0 = 0;
  pLayerCfg.WindowX1 = 480;
  pLayerCfg.WindowY0 = 0;
  pLayerCfg.WindowY1 = 272;
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
通过上面的图片，horizontal synchronization = 1 ， Horizontal back porch=16  
Horizontal start = 1 + 16 =17， 这个注释怎么是43呢？

beyondabcd

/* Layer1 Configuration ------------------------------------------------------*/
   /* Windowing configuration */
  /* In this case all the active display area is used to display a picture then :
     Horizontal start = horizontal synchronization + Horizontal back porch = 43
     Vertical start   = vertical synchronization + vertical back porch     = 12
.......

/* Layer1 Configuration ------------------------------------------------------*/
   /* Windowing configuration */
  /* In this case all the active display area is used to display a picture then :
     Horizontal start = horizontal synchronization + Horizontal back porch = 43
     Vertical start   = vertical synchronization + vertical back porch     = 12
     Horizontal stop = Horizontal start + window width -1 = 43 + 480 -1
     Vertical stop   = Vertical start + window height -1  = 12 + 272 -1      */
  pLayerCfg.WindowX0 = 0;
  pLayerCfg.WindowX1 = 480;
  pLayerCfg.WindowY0 = 0;
  pLayerCfg.WindowY1 = 272;
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
通过上面的图片，horizontal synchronization = 1 ， Horizontal back porch=16  
Horizontal start = 1 + 16 =17， 这个注释怎么是43呢？

eric2013

1. 早期的是HV同步模式，现在基本都用DE模式，水平同步和垂直同步取高或者取低没有影响。
2.  LTDC_PCPOLARITY_IPC可能是早期的命名吧，都是大写字母，现在是这个
    LTDC_PCPolarity_IPC

eric2013

beyondabcd:

/* Layer1 Configuration ------------------------------------------------------*/
   /* Windowing configuration */
  /* In this case all the active display area is used to display a picture then :
     Horizontal start = horizontal synchronization + Horizontal back porch = 43
.......

你给的这个截图看的不太明显啊，可以看我我早期发的这个教程，截图就很容易看出了：
http://www.armbbs.cn/forum.php?mod=viewthread&tid=1958

beyondabcd

eric2013:

你给的这个截图看的不太明显啊，可以看我我早期发的这个教程，截图就很容易看出了：
http://www.armbbs.cn/forum.php?mod=viewthread&tid=1958


.......

/* Layer1 Configuration ------------------------------------------------------*/
   /* Windowing configuration */
  /* In this case all the active display area is used to display a picture then :
     Horizontal start = horizontal synchronization + Horizontal back porch = 43
     Vertical start   = vertical synchronization + vertical back porch     = 12
     Horizontal stop = Horizontal start + window width -1 = 43 + 480 -1
     Vertical stop   = Vertical start + window height -1  = 12 + 272 -1      */
  pLayerCfg.WindowX0 = 0;
  pLayerCfg.WindowX1 = 480;
  pLayerCfg.WindowY0 = 0;
  pLayerCfg.WindowY1 = 272;
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------


根据下面几张你教程里的图，
horizontal synchronization = 2
Horizontal back porch = 2
Horizontal start = horizontal synchronization + Horizontal back porch= 2 + 2 = 4
这么往里代数，算出来对吗？

pjzmj2012

楼主能提供下工程文件吗？我跟楼主是同一块屏幕。

eric2013

pjzmj2012 发表于 2019-7-17 11:08
楼主能提供下工程文件吗？

参考我们的工程就行

pjzmj2012

因为楼主的屏跟我一样，所以我在问楼主要工程的。

eric2013

pjzmj2012 发表于 2019-7-20 09:55
因为楼主的屏跟我一样，所以我在问楼主要工程的。

看此贴，先将背景层点亮

F429驱动TFT裸屏时LTDC时序配置说明（以V6的7寸驱动为例）
http://www.armbbs.cn/forum.php?m ... 8528&fromuid=58
(出处: 安富莱电子论坛)