Conversion of more regular channels using DMA

nj_boelskov · ‎2008-07-22

Posted on July 22, 2008 at 14:44

nj_boelskov · ‎2011-05-17

Posted on May 17, 2011 at 12:40

I'm trying to converte 2 regular ADC channels, but it does not worke. I'm using DMA to put the result in memory.

Every time an adc-conversion is over, a DMA request should be generated, and the data moved to a buffer in memory. But when I check the buffer, it only contains results from the first channel in the ADC-queue.

The length of the ADC-queue is set to 2, and the DMA seems to work correctly. The problem must be that the ADC donÂ´t convert the next channel in the queue or the ADC don't generate a DMA request after end of conversion of the second channel in the queue.

Any ideas how to get this to work?

smart · ‎2011-05-17

Posted on May 17, 2011 at 12:40

it should be something like this

DMA_InitStructure.DMA_PeripheralBaseAddr = ADC1_DR_Address;

DMA_InitStructure.DMA_MemoryBaseAddr = (u32)ADC_RegularConvertedValueTab;

DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;

DMA_InitStructure.DMA_BufferSize =16;

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_Circular;

DMA_InitStructure.DMA_Priority = DMA_Priority_High;

DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;

DMA_Init(DMA_Channel1, &DMA_InitStructure);