Posted on May 17, 2011 at 12:23I'm having trouble getting DMA transfers from the ADC to RAM to SPI2 to work properly. I've followed example 1 from App Note 2548 but can't seem to get the interrup from DMA channel 5 to fire properly. I need it to fire because my process of data transfer requires some smarts to reconfigure which external device I'm writing to every so often. Code from my DMA config function is below. Please let me know what I'm doing wrong.
My ADC DMA transfers appear to work, I just never get an interrupt (or even see flags) for the transfers on channel 5.
Code:
void DMAConfig()
{
DMA_InitTypeDef DMA_InitStructure;
///////////// DMA channel1 configuration from ADC to memory buffer /////////////
DMA_DeInit(DMA_Channel1);
DMA_StructInit(&DMA_InitStructure);
DMA_InitStructure.DMA_PeripheralBaseAddr = (u32)0x4001244C; // ADC1 data register
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)&adcDataBuffer[0];
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize = 3;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word;
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);
// Enable DMA Channel1
DMA_Cmd(DMA_Channel1, ENABLE);
///////////// DMA channel 5 - Storing things to external memory /////////////
DMA_DeInit(DMA_Channel5);
DMA_StructInit(&DMA_InitStructure);
DMA_InitStructure.DMA_PeripheralBaseAddr = (u32)&SPI2->DR; // SPI 2 data register; 0x4000380C
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)&writeBuffer1[0];
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
DMA_InitStructure.DMA_BufferSize = WRITE_BUFFER_SIZE;
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_Normal;
DMA_InitStructure.DMA_Priority = DMA_Priority_VeryHigh;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA_Channel5, &DMA_InitStructure);
// Setup channel 5 interrupts
DMA_ITConfig(DMA_Channel5, DMA_IT_TC, ENABLE); // Interrupt on transfer complete
DMA_Cmd(DMA_Channel5, ENABLE);
// Setup NVIC
NVIC_InitTypeDef NVIC_InitStruct;
NVIC_StructInit(&NVIC_InitStruct);
NVIC_InitStruct.NVIC_IRQChannel = DMAChannel5_IRQChannel;
NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStruct.NVIC_IRQChannelSubPriority = 2;
NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStruct);
} // end DMAConfig
Thanks in advance for any help!
