LCD裸机设计

液晶屏的显示设计需要专门设计驱动和显示控制电路。

在这个实验里，实验板的驱动和显示系统包括S3C2410X片内外设LCD控制器、液晶显示屏的驱动逻辑以及外围驱动电路。

S3C2410X处理器集成了 LCD控制器，主要功能是S3C2410X LCD 控制器用于传输显示数据和
产生控制信号。它并支持屏幕水平和垂直滚动显示。数据的传送采用DMA（直接内存访问）方式，
以达到最小的延迟。它可以支持多种液晶屏： STN，TFT

 

S3c2440芯片

1. TFT_Init()初始化要做的工作：
   1. TFT_InitHardware硬件初始化
      1. Lcd_Port_Init()：

         {

         rGPCUP = 0x00000000;//上拉电阻使能
         rGPCCON = 0xaaaa02a9; //这个与EMbest的代码不一样，VD[0:7],VM,VFRAME,VLINE,VCLK
         
         rGPDUP = 0x00000000;
         rGPDCON=0xaaaaaaaa; //Initialize VD[15:8]

         }

          

         rLCDCON1=(CLKVAL_TFT<<8)|(MVAL_USED<<7)|(3<<5)|(12<<1)|0;
                 // TFT LCD panel,12bpp TFT,ENVID=off
             rLCDCON2=(VBPD<<24)|((LCD_YSIZE_TFT_320240 - 1)<<14)|(VFPD<<6)|(VSPW);
             rLCDCON3=(HBPD<<19)|((LCD_XSIZE_TFT_320240 - 1)<<8)|(HFPD);
             rLCDCON4=(MVAL<<8)|(HSPW);
             rLCDCON5 = (1<<11) | (1<<10) | (1<<9) | (1<<8) | (0<<7) | (0<<6) | (1<<3)  |(BSWP<<1) | (HWSWP);

             rLCDSADDR1=(((U32)LCD_BUFFER>>22)<<21)|M5D((U32)LCD_BUFFER>>1);
             rLCDSADDR2=M5D( ((U32)LCD_BUFFER+(SCR_XSIZE_TFT_320240*LCD_YSIZE_TFT_320240*2))>>1 );
             rLCDSADDR3=(((SCR_XSIZE_TFT_320240-LCD_XSIZE_TFT_320240)/1)<<11)|(LCD_XSIZE_TFT_320240/1);
             rLCDINTMSK|=(3); // MASK LCD Sub Interrupt
             rLPCSEL &= (~7) ;     // Disable LPC3480
             rTPAL=0; // Disable Temp Palette

       

   2. Lcd_PowerEnable(int invpwren, int pwren):

      //GPG4 is setted as LCD_PWREN
      rGPGUP=rGPGUP&(~(1<<4))|(1<<4); // Pull-up disable
      rGPGCON=rGPGCON&(~(3<<8))|(3<<8); //GPG4=LCD_PWREN
      //Enable LCD POWER ENABLE Function
      rLCDCON5=rLCDCON5&(~(1<<3))|(pwren<<3); // PWREN
      rLCDCON5=rLCDCON5&(~(1<<5))|(invpwren<<5); // INVPWREN

   3. Lcd_EnvidOnOff(int onoff)

      if(onoff==1)
              rLCDCON1|=1; // ENVID=ON
          else
              rLCDCON1 =rLCDCON1 & 0x3fffe; // ENVID Off

   4. TFT_ClearSrc()://清屏函数（黑屏)
      1. TFT_SetColor(COLOR_BLACK)  //设置屏幕颜色,为黑色

       

2. 初始化后的程序：

   TFT_SetColor(COLOR_WHITE);
       Delay(1000);   
       TFT_SetColor(COLOR_RED);
       Delay(1000);
       TFT_SetColor(COLOR_GREEN);
       Delay(1000);
       TFT_SetColor(COLOR_BLUE);
       Delay(1000);
       TFT_SetColor(COLOR_YELLOW);
       Delay(1000);
       TFT_SetColor(COLOR_BLACK);
       Delay(500);
       TFT_PutPixel(20,20,COLOR_WHITE);
       TFT_PutPixel(60,20,COLOR_RED);
       TFT_PutPixel(40,20,COLOR_WHITE);
       TFT_PutPixel(80,20,COLOR_BLUE);
       TFT_PutPixel(100,20,COLOR_WHITE);
       TFT_PutPixel(120,20,COLOR_YELLOW);
       Delay(500);
       TFT_Line(30,30,300,30,COLOR_RED);
       Delay(500);
       TFT_Circle(50,100,35,COLOR_GREEN,PAINT_SOLID);
       Delay(500);
       TFT_Circle(200,200,30,COLOR_YELLOW,PAINT_HOLLOW);
       Delay(500);
       TFT_Rectangle(30,180,80,230,COLOR_BLUE,PAINT_SOLID);
       Delay(500);
       TFT_Rectangle(200,80,300,150,COLOR_WHITE,PAINT_HOLLOW);
       Delay(3000);

       TFT_Pitcure(0,0,320,240,Image);
       while(Uart_GetKey() != ESC_KEY);
       Uart_Printf("TFT Test End!\n");

   这个程序就在这里循环了，没有加入中断的处理。还缺少了对其他的控制寄存器进行处理

    

   以上是一个完整的程序了，下面是对上面程序的补充，控制寄存器的设置有些复杂啊！

   UINT32T (*frameBuffer8BitTft640480)[SCR_XSIZE_TFT_640480/4];

   #define LCDFRAMEBUFFER 0x31000000 //_NONCACHE_STARTADDRESS

   #define SCR_XSIZE_TFT_640480     (LCD_XSIZE_TFT_640480*2)

   #define LCD_XSIZE_TFT_640480     (640)

   #define CLKVAL_TFT_640480     (1)

   #define MVAL_USED     (0)

    

    

   frameBuffer8BitTft640480=(UINT32T (*)[SCR_XSIZE_TFT_640480/4])LCDFRAMEBUFFER;
               rLCDCON1=(CLKVAL_TFT_640480<<8)|(MVAL_USED<<7)|(3<<5)|(11<<1)|0;
                 
                  // TFT LCD panel,8bpp TFT,ENVID=off
               rLCDCON2=(VBPD_640480<<24)|(LINEVAL_TFT_640480<<14)|(VFPD_640480<<6)|(VSPW_640480);
               rLCDCON3=(HBPD_640480<<19)|(HOZVAL_TFT_640480<<8)|(HFPD_640480);
               rLCDCON4=(MVAL<<8)|(HSPW_640480);
               rLCDCON5=(1<<11)|(1<<9)|(1<<8);                     //FRM5:6:5,HSYNC and VSYNC are inverted
               rLCDSADDR1=(((UINT32T)frameBuffer8BitTft640480>>22)<<21)|M5D((UINT32T)frameBuffer8BitTft640480>>1);
               rLCDSADDR2=M5D( ((UINT32T)frameBuffer8BitTft640480+(SCR_XSIZE_TFT_640480*LCD_YSIZE_TFT_640480/1))>>1 );
               rLCDSADDR3=(((SCR_XSIZE_TFT_640480-LCD_XSIZE_TFT_640480)/2)<<11)|(LCD_XSIZE_TFT_640480/2);
               rLCDINTMSK|=(3);                                    // MASK LCD Sub Interrupt
               rLPCSEL&=(~7);                                      // Disable LPC3600
               rTPAL=0;                                            // Disable Temp Palette