怎么配置DMA发送数据到GPIO寄存器实现模拟并口

61797826 · 发表于 2014-12-6 15:36:25

怎么配置DMA发送数据到GPIO寄存器实现模拟并口
STM32F051 MDK4.7

程序如下，但不发送（IO口状态不会改变）
请各位大牛不吝赐教，谢谢

/* TIM2 外设时钟使能*/
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
/* 定时器基础配置 */
TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
TIM_TimeBaseStructure.TIM_Period = 0xFF;
TIM_TimeBaseStructure.TIM_Prescaler = 0x0;
TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
/* TIM2触发输出模式选择 */
TIM_SelectOutputTrigger(TIM2, TIM_TRGOSource_Update);
/* TIM2使能 */
TIM_Cmd(TIM2, ENABLE);

/* DMA 通道3配置 */
DMA_DeInit(DMA1_Channel3);
DMA_InitStructure.DMA_PeripheralBaseAddr = GPIOB->ODR;
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)&DATA;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
DMA_InitStructure.DMA_BufferSize = 32;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel3, &DMA_InitStructure);
/* 使能DMA1通道3 */
DMA_Cmd(DMA1_Channel3, ENABLE);

61797826 · 发表于 2014-12-6 15:36:26

搞定结贴。。回原子哥，用一组gpio的其中3个脚控制WR,RS,RD
比直接GPIO丢数据效率高多了

TIM_TimeBaseStructure.TIM_Period = 10;
  TIM_TimeBaseStructure.TIM_Prescaler = 0;
  TIM_TimeBaseStructure.TIM_ClockDivision = 0;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

DMA_DeInit(DMA1_Channel2);
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&GPIOB->ODR;
DMA_InitStructure.DMA_MemoryBaseAddr =(uint32_t)&DATA;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
DMA_InitStructure.DMA_BufferSize = 1024;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc =  DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel2, &DMA_InitStructure);
DMA_Cmd(DMA1_Channel2, ENABLE);
  TIM_DMACmd(TIM2,TIM_DMA_Update,ENABLE);
  TIM_Cmd(TIM2, ENABLE);