Posted on January 01, 2012 at 22:58When I use DMA to trasfer data from memory to SPI2 everything works well util I try do another trasfer, then I reload NDTR register I try enable DMA, but nothing happens, there are no errors in setatus register, just cant set EN bit for stream. When I do deinitialization of DMA stream, and initialize again, it works well.
Siple code where problem occurs:
SPI_InitStructure.SPI_Direction = SPI_Direction_1Line_Tx;
SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
SPI_InitStructure.SPI_DataSize = SPI_DataSize_16b;
SPI_InitStructure.SPI_CPOL = SPI_CPOL_High;
SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge;
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_4;
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
SPI_InitStructure.SPI_CRCPolynomial = 7;
SPI_Init(SPI2, &SPI_InitStructure);
SPI_Cmd(SPI2, ENABLE);
DMA_DeInit(DMA1_Stream4);
DMA_Cmd(DMA1_Stream4, DISABLE);
DMA_InitTypeDef DMA_InitStructure;
DMA_InitStructure.DMA_Channel = DMA_Channel_0;
DMA_InitStructure.DMA_PeripheralBaseAddr = (u32) (&(SPI2->DR));
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t) (&buuf);
DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;
DMA_InitStructure.DMA_BufferSize = (uint32_t) 10;
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_Normal;
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_Stream4, &DMA_InitStructure);
DMA_Cmd(DMA1_Stream4, ENABLE); //THIS TRANSATION WORK WELL
SPI_I2S_DMACmd(SPI2, SPI_I2S_DMAReq_Tx, ENABLE);
while (DMA_GetCurrDataCounter(DMA1_Stream4));
DMA_Cmd(DMA1_Stream4,DISABLE);
SPI_I2S_DMACmd(SPI2, SPI_I2S_DMAReq_Tx, DISABLE);
while (DMA1_Stream4->CR & 0x01 == 1);
DMA1_Stream4->NDTR=17;
DMA_Cmd(DMA1_Stream4,ENABLE); //THIS WILL NOT ENABLE STREAM EN=0
SPI_I2S_DMACmd(SPI2, SPI_I2S_DMAReq_Tx, ENABLE); //HANG HERE
while (DMA_GetCurrDataCounter(DMA1_Stream4));
DMA_Cmd(DMA1_Stream4,DISABLE);
while (DMA1_Stream4->CR & 0x01 == 1);
DMA1_Stream4->M0AR = (uint32_t) (&buuf);
DMA1_Stream4->NDTR=27;
DMA_Cmd(DMA1_Stream4,ENABLE);
#dma-spi
