Posted on December 01, 2014 at 22:49I'm stuck on TIM triggered DMA to SPI.
My DMA Code configuration is as follow:
void DMA_Configuration(void)
{
DMA_InitTypeDef DMA_InitStructure;
/* Enable DMA1 clock */
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
/* Blank DMA Configuration */
DMA_DeInit(DMA1_Channel1);
/* Using the default values at Startup */
DMA_StructInit(&DMA_InitStructure);
/*Changes from the default values */
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)(SPI2->DR); // Address of peripheral the DMA must map to => SPI2 Data Register
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t) TTxBuffer; // Variable to which received data will be stored
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST; // Direction of transfer Memory to Peripheral =Destinatary
DMA_InitStructure.DMA_BufferSize = 32; // BufferSize
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; // We don't want to change the SPI2 Data register
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; // We increment Memory
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; // We define Peripheral Data Size as Byte
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; // We define Memory Data Size as Byte
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; // Circular Mode define
DMA_InitStructure.DMA_Priority = DMA_Priority_High; // High Priority
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; // Memory to Memory Disable
/* Initialize the DMA */
DMA_Init(DMA1_Channel1, &DMA_InitStructure);
/* Enable the DMA transfer half and complete interrupt */
DMA_ITConfig(DMA1_Channel1, DMA_IT_HT, ENABLE); // Half Transfer Interrupt Enable
DMA_ITConfig(DMA1_Channel1, DMA_IT_TC, ENABLE); // Full transfer Interrupt Enable
/* Enable the DMA TIM Triggered */
TIM_DMACmd(TIM2, TIM_DMA_Trigger, ENABLE);
TIM_DMACmd(TIM2, TIM_DMA_Update, ENABLE);
/* Enable DMA1 Channel1 */
DMA_Cmd(DMA1_Channel1, ENABLE);
}
Looking at DMA_CCR1 gives me 0x2AB7 which is ok.
Looking at the SPI2_DR I found no value ; i.e. 0
Franck
