Hello,
I want to trigger a SPI-transfer with a timer. Its like in this post:
https://community.st.com/t5/stm32-mcus-embedded-software/stm32g4-trigger-dma-request-from-spi-to-memory-with-timer/td-p/726370
but I want that an output compare of a timer that triggers an SPI-DMA transfer. The SPI in the STM should run as a slave.
An external ADC is always triggererd from an other timer an sends his data on the SPI as a master. The SPI in the STM should read 1034x16bit values in an buffer.
I began to try it with CUBE-IDE and HAL functions. Than I found this thread here and wrote it for my application (see code below) but also with these functions i could not start the SPI-DMA transfer.
Is it not possible to start a spi-dma-slave for 1034 values?
Many thanks.
uint16_t circular_buffer[1034];
void acq_configure_adc_transfer()
{
// Read SPI1 data after rx to buffer
DMA1_Channel2->CCR = 0x0; //Disable DMA stream
DMA1_Channel2->CPAR = (uint32_t)&SPI1->DR; //Set peripheral data register as destination
DMA1_Channel2->CMAR = (uint32_t)&circular_buffer; //Set source memory region
DMA1_Channel2->CNDTR = sizeof(circular_buffer) ; //Number of items to transfer
DMA1_Channel2->CCR =DMA_CCR_EN | //Enable
DMA_CCR_HTIE | //half transfer interrupt enable
DMA_CCR_TCIE | //transfer complete interrupt enable
DMA_CCR_CIRC | //DMA Circular mode
DMA_PINC_DISABLE | //Do not increment peripheral
DMA_MINC_ENABLE | //Do increment memory
DMA_CCR_PSIZE_0 | //Peripheral data size 0 = 16bit , 1 = 32bit
DMA_CCR_MSIZE_0 | //Memory data size 0 = 16bit , 1 = 32bit
DMA_PRIORITY_VERY_HIGH; //DMA Priority
DMAMUX1_Channel0->CCR = 0;
DMAMUX1_Channel0->CCR |= DMA_REQUEST_TIM1_UP | DMAMUX_CxCR_EGE;
DMAMUX1_Channel1->CCR = 0;
DMAMUX1_Channel1->CCR |= DMA_REQUEST_SPI1_RX | DMAMUX_CxCR_EGE;
HAL_TIM_Base_Start(&htim1); //Start Timer
//Reset SPI1 Configuration Register
SPI1->CR1 = 0;
SPI1->CR2 = SPI_CR2_RXDMAEN | SPI_CR2_TXDMAEN | SPI_CR2_NSSP | SPI_CR2_SSOE | SPI_DATASIZE_16BIT; // TXDMAEN: Enable TX dma, SSOE:SSoutputenable, , Data frame format 16bit
SPI1->CR1 = SPI_CR1_SPE; //Enable SPI, configuration as slaver
//Reset Timer Configuration Registers
TIM1->CR1 = 0;
TIM1->CR2 = 0;
TIM1->DIER = TIM_DIER_UDE; //UDE Update DMA request enable
TIM1->PSC = 500; //Set the prescaler
TIM1->ARR = 1000; //Set the autoreload value (timer interval)
TIM1->CR1 = TIM_CR1_CEN | TIM_CR1_ARPE; //the CEN is set (Counter enable) and ARPE:Auto-reloadpreloadenable is buffered (TIMx_ARR register is buffered)
//Timer is now started and triggers SPI at each overflow
}
