Posted on November 12, 2017 at 19:59HI
I have stm32f407 evaluation board
I use SPI with DMA to read/send the values
in the
evaluation board have accelarometer(spi-connect)
this is the data i want to send and i shuold be get acc(x,y,z)
TX_Buffer[0] = 0xA9;//0x80 |0x29;
TX_Buffer[1] = 0xAB;//0x80 |0x2B;
TX_Buffer[2] = 0xAD;//0x80 |0x2D;
i didn't understand how i send and receive data ?
config DMA and SPI
/////////////////////////////////////
extern volatile uint8_t tempbuff_TX;
extern volatile uint8_t tempbuff_RX;
void CTRLSPI_DMA_init()
{
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);
DMA_InitTypeDef DMA_InitStructure;
DMA_DeInit(DMA2_Stream2);
DMA_DeInit(DMA2_Stream3);
DMA_StructInit(&DMA_InitStructure);
// Configure the Rx part
DMA_InitStructure.DMA_Channel = DMA_Channel_3;
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(SPI1->DR);
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)tempbuff_RX;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
DMA_InitStructure.DMA_BufferSize = NS;
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_Medium;
DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable;
DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
DMA_Init(DMA2_Stream2, &DMA_InitStructure);
DMA_ITConfig(DMA2_Stream2, DMA_IT_TC, ENABLE);
DMA_Cmd(DMA2_Stream2, DISABLE);
//DMA TX.. just modify the relevant parts...
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(SPI2->DR);
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)tempbuff_TX;
DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral;
DMA_InitStructure.DMA_BufferSize = NS;
DMA_Init(DMA2_Stream3, &DMA_InitStructure);
DMA_ITConfig(DMA2_Stream3, DMA_IT_TC, ENABLE);
DMA_Cmd(DMA2_Stream3, DISABLE);
}
void initSpi(void) {
RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);
GPIO_InitTypeDef GPIO_InitStruct;
GPIO_StructInit(&GPIO_InitStruct);
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_DOWN;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7;
GPIO_Init(GPIOA, &GPIO_InitStruct);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource5, GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_SPI1);
GPIO_PinAFConfig(GPIOA, GPIO_PinSource7, GPIO_AF_SPI1);
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_3;
GPIO_Init(GPIOE, &GPIO_InitStruct);
GPIO_SetBits(GPIOE, GPIO_Pin_3);
/*
* configure SPI1 in Mode 0
* CPOL = 0 --> clock is low when idle
* CPHA = 0 --> data is sampled at the first edge
*/
SPI_InitTypeDef SPI_InitStructure;
SPI_I2S_DeInit(SPI1);
SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b;
SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low;
SPI_InitStructure.SPI_CPHA = SPI_CPHA_1Edge;
SPI_InitStructure.SPI_NSS = SPI_NSS_Soft;//| SPI_NSSInternalSoft_Set;
SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_64;// SCLK_freq = APB2_freq / (BaudRatePrescaler + 1)
SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
// SPI_InitStructure.SPI_CRCPolynomial = 0;//7;
SPI_InitStructure.SPI_Mode = SPI_Mode_Master;
SPI_Init(SPI1, &SPI_InitStructure);
// SPI_SSOutputCmd(SPI1, ENABLE);
SPI_Cmd(SPI1, ENABLE);
}
#dma #dma-spi #spi
