STM32 uses SPI mode to drive TFT-LCD optimization code of hx8347 scheme

I need to use one when I am working on a small project recently LCD display , Because I don't usually use this kind of display screen and don't know the commonly used display screen driver IC So I chose this driver IC. After arrival, the code provided by the merchant is only some basic writing points 、 Fill and character display functions , And there is no optimization , In addition, the display screen adopts SPI The maximum speed of protocol affinity test cannot be higher than 36M/bit. Cause the display to write a full screen once 0.4s About time . This speed is almost unacceptable . So based on this IC Driven TFT-LCD The author has optimized some necessary functions . Mainly using SPI coordination STM32 Of DMA To speed up . The optimized speed can reach almost every second 20-30 Around the frame .

First of all SPI and DMA Initialization code part of

void SPI_init()
{
	SPI_InitTypeDef  SPI_InitStructure;
	//SPI1 Mouth initialization 
	/* Configure SPI1 pins: SCK, MISO and MOSI */
	SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;  //SPI1 Set to two-wire full duplex 
	SPI_InitStructure.SPI_Mode = SPI_Mode_Master;		                // Set up SPI1 Main mode 
	SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;		            //SPI Send receive 8 Bit frame structure 
	SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;		                    // The serial clock is not operating , The clock is low 
	SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;	                    // The first clock edge starts sampling data 
	SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;		                    //NSS The signal is controlled by software （ Use SSI position ） management 
	SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_2;  //SPI Baud rate prescaler value is 8
	SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;	                // Data transfer from MSB Bit start 
	SPI_InitStructure.SPI_CRCPolynomial = 7;	                        //CRC The polynomial of the value calculation 
	SPI_Init(SPI1, &SPI_InitStructure);                                 // according to SPI_InitStruct The parameter specified in SPI1 register 
	
	/* Enable SPI1  */
	SPI_Cmd(SPI1, ENABLE);                                              // Can make SPI1 peripherals 
}
void SPI_DAM_init()
{
	DMA_InitTypeDef DMA_InitStructure;
	DMA_DeInit(DMA1_Channel3);  
	DMA_InitStructure.DMA_PeripheralBaseAddr = 0x4001300C;                          	// Set up    Receiving peripherals (0x4001300C)  Address ( source address )
	DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)g_cSbuff;                    	// Set up  SRAM  Storage address ( source address )
	DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;                                // Transmission direction   Memory - peripherals 
	DMA_InitStructure.DMA_BufferSize = DMA_Buff;                           						// Set up  SPI1  Receiving length 
	DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;                  // Peripheral address increment ( unchanged )
	DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;                           // Memory address increment ( change )
	DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;           // Peripheral transmission width ( byte )
	DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;                   // Memory transfer width ( byte )
	DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;                                     // transport , Stop after one transmission , Do not reload 
	DMA_InitStructure.DMA_Priority = DMA_Priority_VeryHigh;                           // Interrupt mode - high ( Level three )
	DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;                                      // Memory to memory mode is prohibited 
	DMA_Init(DMA1_Channel3, &DMA_InitStructure);

	DMA_ITConfig(DMA1_Channel3, DMA_IT_TC, DISABLE);                                   // Turn on  DMA1_Channel3  Transmission complete interrupt 
	DMA_ITConfig(DMA1_Channel3, DMA_IT_TE, DISABLE);                                   // Turn on  DMA1_Channel3  Transmission error interrupt 
	/* Enable SPI1 DMA TX request */
	SPI1->CR2 |= 1<<1;                                                                // Send buffer DMA Can make 
	DMA_Cmd(DMA1_Channel3, DISABLE);                                                  // Turn on  DMA  passageway  DMA1_Channel3
}

Then, the memory management method is used to dynamically give DMA Allocate memory , The following is the optimized filling function

/*******************************************************************************
* Function Name  : SPI1_Send
* Description    : SPI1 Of DMA Mode sending 
* Input          : SPI1_TX_Buff[SPI1_SendBufferSize]
* Output         : None
* Return         : None
* Attention             :  close DMA passageway 3 Must wait before TXE by 1, The waiting busy flag is 0
*******************************************************************************/
void SPI_DMA_TXD(u32 Num)
{

    DMA1_Channel3->CPAR = 0x4001300C; // Peripheral address 
    DMA1_Channel3->CMAR = (u32) g_cSbuff; //mem Address 
    DMA1_Channel3->CNDTR = Num ; // Transmission length 
    DMA1_Channel3->CCR = (0 << 14) | //  Non memory to memory mode 
            (2 << 12) | //  Channel priority is high 
            (0 << 11) | //  Memory data width 8bit
            (0 << 10) | //  Memory data width 8bit
            (0 <<  9) | //  Peripheral data width 8bit
            (0 <<  8) | //  Peripheral data width 8bit
            (1 <<  7) | //  Memory address increment mode 
            (0 <<  6) | //  Peripheral address increment mode ( No increase )
            (0 <<  5) | //  Acyclic mode 
            (1 <<  4) | //  Read from memory 
 //           (1 <<  3) | //  Allow transmission error interrupts 
//            (0 <<  2) | //  Allow half transmission interruptions 
//            (1 <<  1) | //  Allow transmission completion interrupt 
            (1);        //  Channel open 
	while(DMA_GetFlagStatus(DMA1_FLAG_TC3 )==RESET);// Wait for the transfer to complete 
	DMA_ClearFlag(DMA1_FLAG_TC3);// Clear the transmission completion flag bit 
	DMA_Cmd(DMA1_Channel3, DISABLE);// Close channel 
	myfree(0,g_cSbuff);// Free memory 
}

/**********************************************
 Function name ：Lcd Fill function 
 function ： fill Lcd Rectangular area specified on 

 Be careful ：xStart and  yStart Changes as the screen rotates , The position is at the four corners of the rectangle 

 Entrance parameters ：xStart x The starting point of the direction 
          ySrart y The end point of the direction 
          xLong   To select a rectangle x Direction length 
          yLong   To select a rectangle y Direction length 
					Color   Color 
 Return value ： nothing 
***********************************************/
void Lcd_ColorBox(u16 xStart,u16 yStart,u16 xLong,u16 yLong,u16 Color)
{
	u32 i,j;
	i = xLong*yLong;// Number of points entered 
	j = DMA_Buff/2;// The maximum number of points 
	BlockWrite(xStart,xStart+xLong-1,yStart,yStart+yLong-1);
	do
	{
		if(i>j)
		{
			SPI_WriteNumber(Color,j);
			i-=j;
		}
		else
		{
			SPI_WriteNumber(Color,i);
			break;
		}
	}
	while(1);
}

void SPI_WriteNumber(u16 Color,u32 Num)// write in num A little bit 
{
	unsigned int i;
	if(Num <= DMA_Buff)
	{
		Num<<=1;//Num*2
		g_cSbuff = mymalloc(0,Num);// Application memory 
		for(i=0;i<Num;i++,i++)
		{
			*(g_cSbuff+i) = Color>>8;
			*(g_cSbuff+i+1) = Color;// Writing data 
		}
		SPI_CS(0);	
		LCD_RS(1);
		SPI_DMA_TXD(Num);//Num*2
		SPI_CS(1);
	}
}

Specific test project download link ：STM32 Use SPI Way driven HX8347 Of the plan TFT-LCD Optimize the code .-C Document resources -CSDN library https://download.csdn.net/download/qq_24025329/81010005

Limited author , Please correct me if there is any mistake .