Posted on June 23, 2018 at 23:22Hi
I want to parallel data transfer via DMA. I am trying to transfer an array in memory to the GPIO. For this, I thought it would trigger the DMA with the Timer Update event. In this way, I can move the data in memory to the GPIO.
In order to do this I have prepared the following init code.
void HUB75_Tim_DMA_Init(void)
{
__HAL_RCC_TIM3_CLK_ENABLE(); //Enable TIM3;
__HAL_RCC_DMA1_CLK_ENABLE(); //Enable DMA1
TIM_InitStruct.Instance = TIM3;
TIM_InitStruct.Init.Prescaler = 72-1;
TIM_InitStruct.Init.CounterMode = TIM_COUNTERMODE_UP;
TIM_InitStruct.Init.Period = 1000-1;
TIM_InitStruct.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
TIM_InitStruct.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
TIM_InitStruct.Init.RepetitionCounter = 0;
if (HAL_TIM_Base_Init(&TIM_InitStruct) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
DMA_InitStruct.Instance = DMA1_Channel2;
DMA_InitStruct.Init.Direction = DMA_MEMORY_TO_PERIPH;
DMA_InitStruct.Init.PeriphInc = DMA_PINC_DISABLE;
DMA_InitStruct.Init.MemInc = DMA_MINC_ENABLE;
DMA_InitStruct.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD; // 16 bits
DMA_InitStruct.Init.MemDataAlignment = DMA_PDATAALIGN_HALFWORD;
DMA_InitStruct.Init.Mode = DMA_CIRCULAR;
DMA_InitStruct.Init.Priority = DMA_PRIORITY_LOW;
if (HAL_DMA_Init(&DMA_InitStruct) != HAL_OK)
{
_Error_Handler(__FILE__, __LINE__);
}
__HAL_LINKDMA(&TIM_InitStruct,hdma[TIM_DMA_ID_UPDATE],DMA_InitStruct);
HAL_NVIC_SetPriority(DMA1_Channel2_IRQn, 0, 0); // enable DMA IRQ
HAL_NVIC_EnableIRQ(DMA1_Channel2_IRQn);
__HAL_TIM_ENABLE_DMA(&TIM_InitStruct, TIM_DMA_UPDATE);
__HAL_TIM_ENABLE(&TIM_InitStruct);
HAL_DMA_Start_IT(TIM_InitStruct.hdma[TIM_DMA_ID_UPDATE],(uint32_t)&my_buf, (uint32_t)&GPIOA->ODR, 100);
}
But this code did not work. There is no DMA interruption in any way. I must be making a mistake somewhere. Where?
Any idea? How can I do that?
#gpio #stm32 #timer #dma #data #parallel #transfer
