【Start_DSC28034PNT湖人开发板免费体验】+TFT屏显示驱动

Start_DSC28034PNT湖人开发板上配有TFT彩屏接口，见图1所示。

图1 所用接口

所用该接口可为它配置一个2.2寸的TFT显示屏来完成显示任务，其显示分辨率为240*320像素点，该显示屏是以SPI方式进行工作，其接口如图2所示。

图2 显示屏接口

该显示屏与开发板的引脚连接关系为：

CS ---GPIO10
RST--- GPIO9
DC --- GPIO8
SDA--- GPIO16
SCL--- GPIO18
BL --- GPIO7

显示屏所用引脚的配置函数为：

void Init_TFT(void)
{
    EALLOW;
    GpioCtrlRegs.GPAMUX1.bit.GPIO8 = 0;
    GpioCtrlRegs.GPADIR.bit.GPIO8 = 1;
    GpioCtrlRegs.GPAMUX1.bit.GPIO9 = 0;
    GpioCtrlRegs.GPADIR.bit.GPIO9 = 1;
    GpioCtrlRegs.GPAMUX1.bit.GPIO10 = 0;
    GpioCtrlRegs.GPADIR.bit.GPIO10 = 1;
    GpioCtrlRegs.GPAMUX1.bit.GPIO7 = 0;
    GpioCtrlRegs.GPADIR.bit.GPIO7= 1;
    GpioCtrlRegs.GPAMUX2.bit.GPIO18 = 0;
    GpioCtrlRegs.GPADIR.bit.GPIO18 = 1;
    GpioCtrlRegs.GPAMUX2.bit.GPIO16 = 0;
    GpioCtrlRegs.GPADIR.bit.GPIO16 = 1;
    EDIS;
}

所用引脚输出高低电平的语句定义为：

//CLK

#define
LCD_SCK_High()
GpioDataRegs.GPASET.bit.GPIO18= 1

#define
LCD_SCK_Low()
GpioDataRegs.GPACLEAR.bit.GPIO18 = 1

//DIN

#define
LCD_SDI_High()
GpioDataRegs.GPASET.bit.GPIO16= 1

#define
LCD_SDI_Low() GpioDataRegs.GPACLEAR.bit.GPIO16
= 1

//RES

#define
LCD_REST_High()
GpioDataRegs.GPASET.bit.GPIO9= 1

#define
LCD_REST_Low()
GpioDataRegs.GPACLEAR.bit.GPIO9 = 1

//DC

#define
LCD_DC_High()
GpioDataRegs.GPASET.bit.GPIO8= 1

#define
LCD_DC_Low() GpioDataRegs.GPACLEAR.bit.GPIO8
= 1

//CS

#define
LCD_CS_High()
GpioDataRegs.GPASET.bit.GPIO10= 1

#define
LCD_CS_Low()
GpioDataRegs.GPACLEAR.bit.GPIO10 = 1

//BLK

#define
LCD_LED_High()
GpioDataRegs.GPASET.bit.GPIO7= 1

#define
LCD_LED_Low() GpioDataRegs.GPACLEAR.bit.GPIO7
= 1

在GPIO口模拟SPI通讯的方式下，其发送字节数据的函数为：

void LCD_Writ_Bus(unsigned char com)
{
  unsigned char i;
  for(i=0; i<8; i++)
  {
     if(com & 0x80)
     {
         LCD_SDI_High();
     }
     else
     {
          LCD_SDI_Low();
     }
     com = com << 1;
     delay_1us(2);
     LCD_SCK_Low();
     delay_1us(2);
     LCD_SCK_High();
     delay_1us(2);
  }
}

实现指定色彩清屏的功能函数为：

void LCD_Clear(unsigned int Color)
{
    char VH,VL;
    unsigned int i,j;
    VH=Color>>8;
    VL=Color;
    Address_set(0,0,LCD_W-1,LCD_H-1);
    for(i=0;i<LCD_W;i++)
    {
       for (j=0;j<LCD_H;j++)
       {
         LCD_WR_DATA8(VH);
         LCD_WR_DATA8(VL);
       }
    }
}

实现字符显示的函数为：

void LCD_ShowChar(unsigned int x,unsigned int y,char num,char mode)
{
  char temp;
  char pos,t;
  unsigned int x0=x;
  unsigned int colortemp=POINT_COLOR;
  if(x>LCD_W-16||y>LCD_H-16)return;
  num=num-' ';
  Address_set(x,y,x+8-1,y+16-1);
  if(!mode)
  {
     for(pos=0;pos<16;pos++)
     {
         temp=asc2_1608[(unsigned int)num*16+pos];
         for(t=0;t<8;t++)
         {          
           if(temp&0x01)POINT_COLOR=colortemp;
           else POINT_COLOR=BACK_COLOR;
           LCD_WR_DATA(POINT_COLOR);
           temp>>=1;
           x++;
         }
         x=x0;
         y++;
     }
   } else
   {
     for(pos=0;pos<16;pos++)
     {
         temp=asc2_1608[(unsigned int)num*16+pos];
         for(t=0;t<8;t++)
         {           
             if(temp&0x01)LCD_DrawPoint(x+t,y+pos);
             temp>>=1;
         }
     }
   }
   POINT_COLOR=colortemp;
}

实现字符串显示的函数为：

void LCD_ShowString(unsigned int x,unsigned int y,const char *p)
{
    while(*p!='\0')
    {
        if(x>LCD_W-16){x=0;y+=16;}
        if(y>LCD_H-16){y=x=0;}
        LCD_ShowChar(x,y,*p,0);
        x+=8;
        p++;
    }
}

用于显示图标的显示函数为：

void show_tb(unsigned int x,unsigned int y,unsigned int n) 
{
  unsigned int i,j,k;
  unsigned int da;
  k=0;
  for(i=0;i<50;i++)
  {
    for(j=0;j<50;j++)
    {
       if(n==0) da=gImage_tb[k*2];
       ...
       da=da<<8;
       if(n==0) da|=gImage_tb[k*2+1];
       ...
       POINT_COLOR=da;
       LCD_DrawPoint(x-j,y+i); 
       k++;
    }
  }
}

实现显示测试的主程序为：

int main(void)
{
        InitSysCtrl();            
        Init_TFT();
        tft_Init();
        BACK_COLOR=YELLOW;
        POINT_COLOR=RED;
        LCD_Clear(YELLOW);
        LCD_ShowString(80,30,"DSC28034 TEST");
        show_tb(60,20,0);
        while(1);            
       return 0;
}

经程序的编译与下载，其显示效果如图2所示。

图3 显示效果