[MCU] 【AT-START-F403A测评】+2.2'彩色TFT屏的显示驱动

jinglixixi 2020-10-14 20:38 楼主

为了对得起AT32F403A那丰富的存储资源，这次为它配上一个2.2'彩色TFT屏，该显示屏采用SPI接口，故将I2C接口和SPI接口联合起来驱动它。

图1 接口资源

相关引脚输出高低电平的引脚定义为：

#define LCD_CS_High() GPIO_SetBits(GPIOB, GPIO_Pins_13)

#define LCD_CS_Low() GPIO_ResetBits(GPIOB, GPIO_Pins_13) //CS

#define LCD_REST_High() GPIO_SetBits(GPIOB, GPIO_Pins_11)

#define LCD_REST_Low() GPIO_ResetBits(GPIOB, GPIO_Pins_11) //RES

#define LCD_DC_High() GPIO_SetBits(GPIOB, GPIO_Pins_12)

#define LCD_DC_Low() GPIO_ResetBits(GPIOB, GPIO_Pins_12) //DC

#define LCD_SDI_High() GPIO_SetBits(GPIOB, GPIO_Pins_9)

#define LCD_SDI_Low() GPIO_ResetBits(GPIOB, GPIO_Pins_9)//SDI

#define LCD_SCK_High() GPIO_SetBits(GPIOB, GPIO_Pins_8)

#define LCD_SCK_Low() GPIO_ResetBits(GPIOB, GPIO_Pins_8)//SCK

#define LCD_LED_High() GPIO_SetBits(GPIOB, GPIO_Pins_14)

#define LCD_LED_Low() GPIO_ResetBits(GPIOB, GPIO_Pins_14) //BLK

由于与前面介绍的彩色OLED屏所用的引脚位置一致，一个奇异的现象出现了，在等待程序下载的显示屏竟显示出了内容，见图2~图4所示。

OLED屏的程序竟能驱动TFT屏，而且图像完整，只不过显示的内容是镜像的，且颜色互补。

是不是很神奇！

图2 显示字符串

图3 显示汉字

图4 显示图标

图5 原OLED屏显示效果

在更新程序后，使用红色进行清屏后的效果如图6所示。

图6 红色清屏效果

该2.2寸TFT彩屏的初始化函数为：

void tft_Init(void)
{
    LCD_REST_Low();  //Lcd_Reset()
    Delay_ms(20);    //delay_ms(20);
    LCD_REST_High();
    Delay_ms(20);
    LCD_CS_Low(); 
    LCD_WR_REG(0xCB);  //Lcd_WriteIndex(0xCB); 
    LCD_WR_DATA8(0x39);//Lcd_WriteData(0x39);
    LCD_WR_DATA8(0x2C);
    LCD_WR_DATA8(0x00);
    LCD_WR_DATA8(0x34);
    LCD_WR_DATA8(0x02);
    LCD_WR_REG(0xCF); 
    LCD_WR_DATA8(0x00);
    LCD_WR_DATA8(0XC1);
    LCD_WR_DATA8(0X30);
    LCD_WR_REG(0xE8); 
    LCD_WR_DATA8(0x85);
    LCD_WR_DATA8(0x00);
    LCD_WR_DATA8(0x78);
    LCD_WR_REG(0xEA); 
    LCD_WR_DATA8(0x00);
    LCD_WR_DATA8(0x00);
    LCD_WR_REG(0xED); 
    LCD_WR_DATA8(0x64);
    LCD_WR_DATA8(0x03);
    LCD_WR_DATA8(0X12);
    LCD_WR_DATA8(0X81);
    LCD_WR_REG(0xF7); 
    LCD_WR_DATA8(0x20);
    LCD_WR_REG(0xC0);     //Power control
    LCD_WR_DATA8(0x23);   //VRH[5:0]
    LCD_WR_REG(0xC1);     //Power control
    LCD_WR_DATA8(0x10);   //SAP[2:0];BT[3:0]
    LCD_WR_REG(0xC5);     //VCM control
    LCD_WR_DATA8(0x3e);   //?????
    LCD_WR_DATA8(0x28);
    LCD_WR_REG(0xC7);     //VCM control2
    LCD_WR_DATA8(0x86);
    LCD_WR_REG(0x36);     // Memory Access Control
    LCD_WR_DATA8(0x48);
    LCD_WR_REG(0x3A);
    LCD_WR_DATA8(0x55);
    LCD_WR_REG(0xB1);
    LCD_WR_DATA8(0x00);
    LCD_WR_DATA8(0x18);
    LCD_WR_REG(0xB6);    // Display Function Control
    LCD_WR_DATA8(0x08);
    LCD_WR_DATA8(0x82);
    LCD_WR_DATA8(0x27);
    LCD_WR_REG(0xF2);    // 3Gamma Function Disable
    LCD_WR_DATA8(0x00);
    LCD_WR_REG(0x26);    //Gamma curve selected
    LCD_WR_DATA8(0x01);
    LCD_WR_REG(0xE0);    //Set Gamma
    LCD_WR_DATA8(0x0F);
    LCD_WR_DATA8(0x31);
    LCD_WR_DATA8(0x2B);
    LCD_WR_DATA8(0x0C);
    LCD_WR_DATA8(0x0E);
    LCD_WR_DATA8(0x08);
    LCD_WR_DATA8(0x4E);
    LCD_WR_DATA8(0xF1);
    LCD_WR_DATA8(0x37);
    LCD_WR_DATA8(0x07);
    LCD_WR_DATA8(0x10);
    LCD_WR_DATA8(0x03);
    LCD_WR_DATA8(0x0E);
    LCD_WR_DATA8(0x09);
    LCD_WR_DATA8(0x00);
    LCD_WR_REG(0XE1);    //Set Gamma
    LCD_WR_DATA8(0x00);
    LCD_WR_DATA8(0x0E);
    LCD_WR_DATA8(0x14);
    LCD_WR_DATA8(0x03);
    LCD_WR_DATA8(0x11);
    LCD_WR_DATA8(0x07);
    LCD_WR_DATA8(0x31);
    LCD_WR_DATA8(0xC1);
    LCD_WR_DATA8(0x48);
    LCD_WR_DATA8(0x08);
    LCD_WR_DATA8(0x0F);
    LCD_WR_DATA8(0x0C);
    LCD_WR_DATA8(0x31);
    LCD_WR_DATA8(0x36);
    LCD_WR_DATA8(0x0F);
    LCD_WR_REG(0x11);    //Exit Sleep
    Delay_ms(120);
    LCD_WR_REG(0x29);    //Display on
    LCD_WR_REG(0x2c);
}

它的色彩清屏函数为：

void LCD_Clear(unsigned int Color)
{
     char VH,VL;// LCD_W= 240   LCD_H =320
     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);  
        }
    }
}

在制备了图标文件后，所制作的界面效果如图7所示。