Question
DMA triggering not running for an input capture timer channel
Posted on October 31, 2012 at 16:38
I want to capture a systick time by occurence of an edge. I see the value is captured but the DMA is not done. Why? (STM32F4)
TIM_ICInitTypeDef TIM_ICInitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1, ENABLE);
DMA_InitTypeDef DMA_InitStructure;
DMA_DeInit(DMA1_Stream0);
DMA_InitStructure.DMA_Channel = DMA_Channel_2;
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&SysTick->VAL ;
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)×tampOfEncoderEdge;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
DMA_InitStructure.DMA_BufferSize = 1;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Disable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
DMA_InitStructure.DMA_MemoryDataSize = DMA_PeripheralDataSize_Word;
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;
DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
DMA_Init(DMA1_Stream0, &DMA_InitStructure);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);
TIM_DeInit(TIM4);
TIM_ICInitStructure.TIM_Channel = TIM_Channel_1;
TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_BothEdge;
TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
TIM_ICInitStructure.TIM_ICFilter = 0x0;
TIM_ICInit(TIM4, &TIM_ICInitStructure);
TIM_Cmd(TIM4, ENABLE);
DMA_Cmd(DMA1_Stream0, ENABLE);
TIM_DMACmd(TIM4, TIM_DMA_CC1, ENABLE);