STM32 SPI+DMA刷LCD屏

 1 void SPI_GPIO_Init(void)
 2 {
 3     GPIO_InitTypeDef GPIO_InitStructure;
 4     SPI_InitTypeDef  SPI_InitStructure;
 5      
 6     NVIC_InitTypeDef NVIC_InitStructure;
 7        
 8     RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE );//PORTB时钟使能 
 9     RCC_APB1PeriphClockCmd(RCC_APB1Periph_SPI2,  ENABLE );//SPI2时钟使能 
10     
11     /* DMA1 clock enable */
12     RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, DISABLE);
13     RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
14     
15     GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
16     GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  //PB13/14/15复用推挽输出 
17     GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
18     GPIO_Init(GPIOB, &GPIO_InitStructure);//初始化GPIOB
19     
20     GPIO_SetBits(GPIOB,GPIO_Pin_13|GPIO_Pin_14|GPIO_Pin_15);  //PB13/14/15上拉
21     
22     SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;  //设置SPI单向或者双向的数据模式:SPI设置为双线双向全双工
23     SPI_InitStructure.SPI_Mode = SPI_Mode_Master;        //设置SPI工作模式:设置为主SPI
24     SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;        //设置SPI的数据大小:SPI发送接收8位帧结构
25     SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;        //串行同步时钟的空闲状态为高电平
26     SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;    //串行同步时钟的第二个跳变沿（上升或下降）数据被采样
27     SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;        //NSS信号由硬件（NSS管脚）还是软件（使用SSI位）管理:内部NSS信号有SSI位控制
28     SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_2;        //定义波特率预分频的值:波特率预分频值为256
29     SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;    //指定数据传输从MSB位还是LSB位开始:数据传输从MSB位开始
30     SPI_InitStructure.SPI_CRCPolynomial = 7;    //CRC值计算的多项式
31     SPI_Init(SPI2, &SPI_InitStructure);  //根据SPI_InitStruct中指定的参数初始化外设SPIx寄存器
32 
33     NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
34     NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel5_IRQn;
35     NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
36     NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
37     NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
38     NVIC_Init(&NVIC_InitStructure);
39     
40     //SPI_I2S_DMACmd(SPI2, SPI_I2S_DMAReq_Tx, DISABLE);
41     SPI_Cmd(SPI2, ENABLE);          
42 } 

 1 void DMA_LCD_Send( const UINT8 *ptdate,UINT16 len)
 2 {
 3     DMA_InitTypeDef  DMA_InitStructure;
 4 
 5     OLED_DC_Set();//写数据
 6     OLED_CS_Clr();
 7     DMA_DeInit(DMA1_Channel5);
 8     DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&SPI2->DR;
 9     DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)ptdate;//SPI2_Tx_Buf;
10     DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
11     DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
12     DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
13     DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
14     DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;
15     DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
16     DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;
17     DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
18     DMA_Init(DMA1_Channel5, &DMA_InitStructure);
19     DMA_Cmd(DMA1_Channel5, DISABLE );  //关闭DMA1 所指示的通道      
20     
21     DMA_SetCurrDataCounter(DMA1_Channel5,len);//DMA通道的DMA缓存的大小
22     //DMA_ClearFlag(DMA1_FLAG_TC5);//清除通道传输完成标志  
23     DMA_ClearITPendingBit(DMA1_IT_TC5);
24 
25     SPI_I2S_DMACmd(SPI2, SPI_I2S_DMAReq_Tx, ENABLE);
26     DMA_ITConfig(DMA1_Channel5, DMA_IT_TC, ENABLE); 
27     DMA_Cmd(DMA1_Channel5, ENABLE);  //使能USART1 TX DMA1 所指示的通道 
28     
29     //while(RESET == DMA_GetFlagStatus(DMA1_FLAG_TC5));    //判断通道传输完成
30     //DMA_ClearFlag(DMA1_FLAG_TC5);//清除通道传输完成标志
31 } 

1 void DMA1_Channel5_IRQHandler(void) 
2 {
3     if (DMA_GetITStatus(DMA1_IT_TC5)) {
4         DMA_ClearITPendingBit(DMA1_IT_TC5);
5         //DMA_Cmd(DMA1_Channel5, DISABLE);
6         OLED_CS_Set();
7     }
8 }