为什么AD的转换结果用DMA读取就不对了呢？ 如能解决，万分感谢！！！

zhnh8

[mw_shl_code=c,true]#include “stm32f10x.h” #define AD_BUFFERSIZE 1 extern u16 ad_buffer[AD_BUFFERSIZE]; u16 val_temp; u16 cur_value; void Sample_Time_Init(void) { TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure; RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE); TIM_TimeBaseStructure.TIM_Period = 99; //?ú?ú1000hz?????? TIM_TimeBaseStructure.TIM_Prescaler = 719; //720·??? TIM_TimeBaseStructure.TIM_ClockDivision = 0x0; TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure); TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE); //???¨?±?÷??????????????1???×?????????????? TIM_Cmd(TIM2, ENABLE); } void TIM2_IRQHandler(void) { if(TIM_GetITStatus(TIM2, TIM_IT_Update) == SET) { val_temp = ADC1->DR; cur_value = ad_buffer[0]; } TIM_ClearITPendingBit(TIM2, TIM_IT_Update); } #include "stm32f10x.h" #define AD_BUFFERSIZE 1 u16 ad_buffer[AD_BUFFERSIZE]; void Cur_AD_Init(void) { DMA_InitTypeDef DMA_InitStructure; GPIO_InitTypeDef GPIO_InitStructure; ADC_InitTypeDef ADC_InitStructure ; RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE); DMA_DeInit(DMA1_Channel1); DMA_InitStructure.DMA_PeripheralBaseAddr = 0x4001244C; //(u32)&ADC1->DR; DMA_InitStructure.DMA_MemoryBaseAddr = (u32)&ad_buffer; DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; //???è×÷???????? DMA_InitStructure.DMA_BufferSize = AD_BUFFERSIZE; DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //???è???·??±? DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Disable; //???????·???? DMA_InitStructure.DMA_PeripheralDataSize = DMA_MemoryDataSize_HalfWord ; DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord ; DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; DMA_InitStructure.DMA_Priority = DMA_Priority_Medium; DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; DMA_Init(DMA1_Channel1, &DMA_InitStructure); RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_ADC1 | RCC_APB2Periph_AFIO, ENABLE); RCC_ADCCLKConfig(RCC_PCLK2_Div8); //ad?????ù??????9Mhz GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2; //???¨??2????×??? GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN; GPIO_Init(GPIOA, &GPIO_InitStructure); ADC_InitStructure.ADC_Mode = ADC_Mode_Independent; ADC_InitStructure.ADC_ScanConvMode = DISABLE; ADC_InitStructure.ADC_ContinuousConvMode = ENABLE; ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None; ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; ADC_InitStructure.ADC_NbrOfChannel = 1; ADC_Init(ADC1, &ADC_InitStructure); ADC_RegularChannelConfig(ADC1, ADC_Channel_2, 1, ADC_SampleTime_239Cycles5); //252??×??????? ADC_DMACmd(ADC1, ENABLE); //????????ADC?×?? ADC_Cmd(ADC1, ENABLE); ADC_ResetCalibration(ADC1); while(ADC_GetResetCalibrationStatus(ADC1)); ADC_StartCalibration(ADC1); while(ADC_GetCalibrationStatus(ADC1)); DMA_Cmd(DMA1_Channel1, ENABLE); ADC_SoftwareStartConvCmd(ADC1, ENABLE); //?í??????ADC×??? } [/mw_shl_code]

正点原子

参考论坛其他网友的ADC+DMA例程，论坛有很多这样的代码。