STM32F030C8的DMA问题

张云锋

大家好，小弟遇到个问题，STM32F030C8的SPI上使用DMA

[mw_shl_code=c,true]char Buffer[5]={0x55,0xff,0xee,0x44,0x33}; DMA_InitTypeDef DMA_InitStructure; NVIC_InitTypeDef NVIC_InitStructure; void dmainit() { /* DMA1 channel1 configuration ---------------------------------------------*/ /* Enable DMA1 clock --------------------------------------------------------*/ RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE); DMA_DeInit(DMA1_Channel3); DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)SPI1->DR; //spi1 dr DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)Buffer; DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST; //m to spi DMA_InitStructure.DMA_BufferSize = 5;//sizeof(); DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;//DMA_Mode_Normal; DMA_InitStructure.DMA_Priority = DMA_Priority_High; DMA_InitStructure.DMA_M2M = DMA_M2M_Enable; DMA_Init(DMA1_Channel3, &DMA_InitStructure); /* Enable DMA1 Channel3 transfer */ DMA_Cmd(DMA1_Channel3, ENABLE); }[/mw_shl_code]

[mw_shl_code=c,true]void spiinit() { GPIO_InitTypeDef GPIO_InitStructure; SPI_InitTypeDef SPI_InitStructure; RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA,ENABLE); RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1,ENABLE); GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7 ; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_Level_3; GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; GPIO_Init(GPIOA, &GPIO_InitStructure); GPIO_PinAFConfig(GPIOA, GPIO_PinSource7, GPIO_AF_0); GPIO_PinAFConfig(GPIOA, GPIO_PinSource6, GPIO_AF_0); GPIO_PinAFConfig(GPIOA, GPIO_PinSource5, GPIO_AF_0); SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex; SPI_InitStructure.SPI_Mode = SPI_Mode_Master; SPI_InitStructure.SPI_DataSize = SPI_DataSize_8b; SPI_InitStructure.SPI_CPOL = SPI_CPOL_Low; SPI_InitStructure.SPI_CPHA = SPI_CPHA_2Edge; SPI_InitStructure.SPI_NSS = SPI_NSS_Soft; SPI_InitStructure.SPI_BaudRatePrescaler = SPI_BaudRatePrescaler_32; SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB; SPI_Init(SPI1, &SPI_InitStructure); SPI_Cmd(SPI1, ENABLE); SPI_I2S_DMACmd(SPI1, SPI_I2S_DMAReq_Tx, ENABLE); } int main() { SystemInit(); //kaiqi 48M CLK spiinit();dmainit();while(1);}[/mw_shl_code] [mw_shl_code=c,true] [/mw_shl_code]

SPI和DMA初始化如上图所示，试验中逻辑分析仪采集SPI1的 MOSI端口，始终为低电平，无数据输出，忽略DMA以后手动往SPI1.DR写入数据，SPI是能工作的，有数据发送，可见SPI正确。DMA第一次使用，请大神指点，是哪里出了差错，对比了好几个例程始终无法解决。

ricefat

DMA_Cmd(DMA1_Channel1, ENABLE);
这一句就开始传数据了
所以这一句应该放在SPI初始化之后

张云锋

回复【2楼】ricefat:
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谢谢回复，试过了，还是不行，改成DMA1_Channel3也试过了，不行

张云锋

回复【2楼】ricefat:
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解决了，这一句应该这么写。。。
加个&（），这。。。。。
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&(SPI1->DR);    //spi1 dr

ricefat

回复【4楼】张云锋:
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原来是地址错了