TFTLCD display experiment of mini plate based on punctual atom stm32

This chapter will talk about TFTLCD Display experiments , Xiaobai sums up , If there is a mistake , Please give me your advice .

One 、TFTLCD brief introduction

1.TFT-LCD Thin film transistor liquid crystal display .TFT-LCD have ： Good brightness 、 High contrast 、 Strong sense of hierarchy 、 Bright color and other characteristics . It's the most mainstream LCD Monitor . It is widely used in various electronic products .

Be careful ： The module is 3.3V Powered by electricity , I won't support it 5V Of voltage MCU, If it is 5VMCU, The signal line must be connected in series 120 Ohm resistance is used .

2.2.8 " TFTLCD The schematic diagram of the module is as follows ：

In the picture X-,Y-,Y+,X+ Should and XPT2046 Touch screen connection , The schematic diagram of touch screen is as follows ：

The interfaces we may use are as follows ：

1.CS：TFTLCD Piece of optional signal .

2.WR： towards TFTLCD Write data .

3.RD： from TFTLCD Reading data .

4.D[15：0]( Zero to fifteen means )：16 Bit bidirectional data line .

5.RST： Hard reset TFTLCD.

6.RS： command / Data signs （0, Read and write commands ;1, Read and write data ）.

7.BL_CTR: Backlight control signal

8. Touch screen interface signal ：T_MISO/T_MOSI/T_PEN/T_CS/T_CLK( These functions need to be determined , If not required, it is not necessary to set ).

3.TFTLCD Modular 8080 Read simultaneously / The process of writing ：

1. First write... According to the need / The type of data read , Set up RS For the high （ data ）/ low （ command ）, And then pull down the selection , Choose ILI9341, And then we read the data , Or write the data set RD/WR For low , then ：

（1） Reading data ： stay RD The rising edge of , Read the data on the data line ;

（2） Writing data ： stay WR The rising edge of , Write data to ILI9341 Inside .

4.TFTLCD The driving process of ：

5.ILI9341 use RGB565 Format to store color data ：

R5: There are five red ,G6： There are six green ,B5： There are five blue , Together it is RGB565 Format .

for example ：0xf800 It is pure red .

6. Instruction Introduction ：

（1）0xD3: It's a test LCD Models of tools , Because the model can be tested , Therefore, the portability of the code is enhanced .

（2）0x36: To store access control instructions , It can control the reading and writing direction of the memory , Realization GRAM Self increasing mode , Increase speed

（3）0x2A: From left to right , From top to bottom , Set up x Coordinates of .

（4）0x2B: From left to right , From top to bottom , Set up y Coordinates of .

（5）0x2C: Set the color data .

（6）0x2E: Read video memory , That is, the general color .

7. On hardware ,TFTLCD Module and MiniSTM32 Development board IO The oral correspondence is as follows ： 
 LCD_LED Corresponding PC10; 
 LCD_CS Corresponding PC9; 
 LCD _RS Corresponding PC8; 
 LCD _WR Corresponding PC7; 
 LCD _RD Corresponding PC6; 
 LCD _D[17:1] Corresponding PB[15:0]; 

Two 、 software design

1. Let's first introduce a lcd An important structure of ：

typedef struct 
{ 
 u16 width; //LCD  Width  
 u16 height; //LCD  Height  
 
 u16 id; //LCD ID 
 u8 dir; // Horizontal screen or vertical screen control ：0, Vertical screen ;1, Horizontal screen . 
 u16 wramcmd; // Start writing  gram  Instructions  
 u16 setxcmd; // Set up  x  Coordinate command  
 u16 setycmd; // Set up  y  Coordinate command  
}_lcd_dev; 
//LCD  Parameters  
extern _lcd_dev lcddev; // management  LCD  Important parameter  

2. Write data functions ：

// Write data functions  
#define LCD_WR_DATA(data){\ 
LCD_RS_SET;\ 
LCD_CS_CLR;\ 
DATAOUT(data);\ 
LCD_WR_CLR;\ 
LCD_WR_SET;\ 
LCD_CS_SET;\ 
} 

3. Write register command function ：

// Write register function  
//data: Register values  
void LCD_WR_REG(u16 data) 
{ 
 LCD_RS_CLR;// Write the address  
 LCD_CS_CLR; 
 DATAOUT(data); 
 LCD_WR_CLR; 
 LCD_WR_SET; 
 LCD_CS_SET; 
}

4. Read register data function ：

// read  LCD  Register data  
// Return value : The value read  
u16 LCD_RD_DATA(void) 
{ 
 u16 t; 
 GPIOB->CRL=0X88888888; //PB0-7  Pull up input  
 GPIOB->CRH=0X88888888; //PB8-15  Pull up input  
 GPIOB->ODR=0X0000; // All output  0 
 LCD_RS_SET; 
 LCD_CS_CLR; 
 LCD_RD_CLR; // Reading data ( When reading registers , There is no need to read  2  Time ) 
 if(lcddev.id==0X8989)delay_us(2);//FOR 8989, Time delay  2us 
 t=DATAIN; 
 LCD_RD_SET; 
 LCD_CS_SET; 
 GPIOB->CRL=0X33333333; //PB0-7  Pull up output  
 GPIOB->CRH=0X33333333; //PB8-15  Pull up output  
 GPIOB->ODR=0XFFFF; // All output high  
 return t; 
} 

5. LCD Register operation function

//LCD_Reg: Register number  
//LCD_RegValue: Value to write  
void LCD_WriteReg(u16 LCD_Reg,u16 LCD_RegValue) 
{ 
 LCD_WR_REG(LCD_Reg); 
 LCD_WR_DATA(LCD_RegValue); 
} 
// Read register  
//LCD_Reg: Register number  
// Return value : The value read  
u16 LCD_ReadReg(u16 LCD_Reg) 
{ 
 LCD_WR_REG(LCD_Reg); // Write the register number to be read  
 return LCD_RD_DATA(); 
} 

6. Set cursor function ：

// Set cursor position  
//Xpos: Abscissa  
//Ypos: Ordinate  
void LCD_SetCursor(u16 Xpos, u16 Ypos) 
{ 
 if(lcddev.id==0X9341||lcddev.id==0X5310) 
 { 
 LCD_WR_REG(lcddev.setxcmd); 
 LCD_WR_DATA(Xpos>>8); 
 LCD_WR_DATA(Xpos&0XFF); 
 LCD_WR_REG(lcddev.setycmd); 
 LCD_WR_DATA(Ypos>>8); 
 LCD_WR_DATA(Ypos&0XFF); 
 }else if(lcddev.id==0X6804) 
 { 
 if(lcddev.dir==1)Xpos=lcddev.width-1-Xpos;// Horizontal screen processing  
 LCD_WR_REG(lcddev.setxcmd); 
 LCD_WR_DATA(Xpos>>8); 
 LCD_WR_DATA(Xpos&0XFF); 
 LCD_WR_REG(lcddev.setycmd); 
 LCD_WR_DATA(Ypos>>8); 
 LCD_WR_DATA(Ypos&0XFF); 
 }else if(lcddev.id==0X5510) 
 { 
 
 LCD_WR_REG(lcddev.setxcmd); 
 LCD_WR_DATA(Xpos>>8); 
 LCD_WR_REG(lcddev.setxcmd+1); 
 LCD_WR_DATA(Xpos&0XFF); 
 LCD_WR_REG(lcddev.setycmd); 
 LCD_WR_DATA(Ypos>>8); 
 LCD_WR_REG(lcddev.setycmd+1); 
 LCD_WR_DATA(Ypos&0XFF); 
 }else 
 { 
 if(lcddev.dir==1)Xpos=lcddev.width-1-Xpos;// The horizontal screen is actually turning  x,y  coordinate  
 LCD_WriteReg(lcddev.setxcmd, Xpos); 
 LCD_WriteReg(lcddev.setycmd, Ypos); 
 } 
}

Due to too much actual code , Commentable QQ, I'll send you the source file , I am writing 51 and 32 Writing code , You can have a private chat .