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STM32F4-Discovery_FW_V1.1.0固件库中的Peripheral_Examples例子中中的“DAC_SignalsGeneration”工程，举例 /** * @brief DAC Channel1 Escalator Configuration * @param None * @retval None */ void DAC_Ch1_EscalatorConfig(void) { DMA_InitTypeDef DMA_InitStructure; /* DAC channel1 Configuration */ DAC_InitStructure.DAC_Trigger = DAC_Trigger_T6_TRGO; DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None; DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable; DAC_Init(DAC_Channel_1, &DAC_InitStructure); /* DMA1_Stream6 channel7 configuration **************************************/ DMA_DeInit(DMA1_Stream6); DMA_InitStructure.DMA_Channel = DMA_Channel_7; DMA_InitStructure.DMA_PeripheralBaseAddr = DAC_DHR8R1_ADDRESS; DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)&Escalator8bit; DMA_InitStructure.DMA_BufferSize = 6; DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral; DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; DMA_InitStructure.DMA_Priority = DMA_Priority_High; 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(DMA1_Stream6, &DMA_InitStructure); /* Enable DMA1_Stream6 */ DMA_Cmd(DMA1_Stream6, ENABLE); /* Enable DAC Channel1 */ DAC_Cmd(DAC_Channel_1, ENABLE); /* Enable DMA for DAC Channel1 */ DAC_DMACmd(DAC_Channel_1, ENABLE); } 其中DAC_Channel_1跟DMA1_Stream6的DMA_Channel_7对，明显不对。 
不知道是出于什么原因。 而函数void DAC_Ch2_SineWaveConfig(void)却是DAC_Channel_2跟DMA1_Stream5的DMA_Channel_7对。。。。有解释吗？？ |
我亲自测试过该工程，只开DAC1或是只开DAC2时，是没有输出的！！
有很多地方不严够谨！