I have a working code for SPI with DMA support added. Now I want to improve the speed of operation.
I am using an STM32F427 controller.
#define SPIx_Mode SPI_MODE_MASTER
#define SPIx_Direction SPI_DIRECTION_1LINE
#define SPIx_DataSize SPI_DATASIZE_16BIT
#define SPIx_ClkPolarity SPI_POLARITY_HIGH
#define SPIx_ClkPhase SPI_PHASE_1EDGE
#define SPIx_Nss SPI_NSS_SOFT
#define SPIx_BaudRatePrescaler SPI_BAUDRATEPRESCALER_4
#define SPIx_FirstBit SPI_FIRSTBIT_MSB
#define SPIx_TiMode SPI_TIMODE_DISABLE
#define SPIx_CrcCalc SPI_CRCCALCULATION_DISABLE
#define SPIx_CrcPolynomial 0
/* DMA configuration */
hdma_tx.Instance = SPIx_TX_DMA_STREAM;
hdma_tx.Init.Channel = SPIx_TX_DMA_CHANNEL;
hdma_tx.Init.Direction = DMA_MEMORY_TO_PERIPH;
hdma_tx.Init.PeriphInc = DMA_PINC_DISABLE;
hdma_tx.Init.MemInc = DMA_MINC_ENABLE;
hdma_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;
hdma_tx.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;
hdma_tx.Init.Mode = DMA_NORMAL;
hdma_tx.Init.Priority = DMA_PRIORITY_HIGH;
hdma_tx.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
hdma_tx.Init.FIFOThreshold = DMA_FIFO_THRESHOLD_FULL;
hdma_tx.Init.MemBurst = DMA_MBURST_INC4;
hdma_tx.Init.PeriphBurst = DMA_PBURST_INC4;
Current working code
/* SPI Transmit function, which is a wrapper for SPI transfer using DMA */
void spi2_dataTransfer(uInt16 *TxBuffer, uInt8 size)
{
HAL_GPIO_WritePin(SPIx_NSS_Port, SPIx_NSS_Pin, GPIO_PIN_RESET);
HAL_SPI_Transmit_DMA(&SPIx_handle, (uint8_t *)TxBuffer, size);
while (HAL_SPI_GetState(&SPIx_handle) != HAL_SPI_STATE_READY);
HAL_GPIO_WritePin(SPIx_NSS_Port, SPIx_NSS_Pin, GPIO_PIN_SET);
}
above mentioned code is working fine, but the while condition is causing some delay.
I want to avoid it.
So, I use below code.
/* SPI Transmit function, which is a wrapper for SPI transfer using DMA */
void spi2_dataTransfer(uInt16 *TxBuffer, uInt8 size)
{
HAL_GPIO_WritePin(SPIx_NSS_Port, SPIx_NSS_Pin, GPIO_PIN_RESET);
HAL_SPI_Transmit_DMA(&SPIx_handle, (uint8_t *)TxBuffer, size);
// while (HAL_SPI_GetState(&SPIx_handle) != HAL_SPI_STATE_READY);
// HAL_GPIO_WritePin(SPIx_NSS_Port, SPIx_NSS_Pin, GPIO_PIN_SET);
}
// After successful transfer NSS is put high from HAL_SPI_TxCpltCallback.
void HAL_SPI_TxCpltCallback(SPI_HandleTypeDef *SPIx_handle)
{
HAL_GPIO_WritePin(SPIx_NSS_Port, SPIx_NSS_Pin, GPIO_PIN_SET);
}
But this is not working. why ? please help
Edit : Issue resolved, above code is working. Unable to delete the post
